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This article discusses the concept of quiescence and dormancy in plants and their importance in plant development, acclimation, and survival. The article highlights recent research on the molecular and metabolic regulation of quiescence, as well as the ecological modeling and molecular perception of temperature in relation to dormancy. The integration of hormone and cell-to-cell signaling, as well as the role of epigenetic mechanisms in establishing and maintaining dormancy, is also explored. The article concludes by emphasizing the potential applications of this research in enhancing plant resilience in the face of climate change. [Extracted from the article]

The NTL (NAC with transmembrane motif 1-like) transcription factors with a conserved transmembrane motif are members of the NAC family and are important in plant development and in response to stress. However, knowledge of their regulatory pathways is scarce, especially under heat stress. Here, we cloned and identified a novel lily (Lilium longiflorum) NTL gene, LlNAC014, that increases thermotolerance. High temperature repressed LlNAC014 expression but activated its protein. LlNAC014 contained a typical transmembrane motif at its far C-terminus and was normally located on membranes, but under heat stress it entered the nucleus as a transcription factor. LlNAC014 also has a transactivation domain at its C-terminus, and its active form, LlNAC014ΔC, could function as a trans-activator in both yeast and plant cells. LlNAC014ΔC overexpression in lily and Arabidopsis increased thermotolerance, and also caused growth defects; silencing LlNAC014 in lily decreased thermotolerance. LlNAC014ΔC could constitutively activate the heat stress response by inducing the expression of heat-responsive genes, some of which were dependent on the HSF (heat stress transcription factor) pathway. Further analysis showed that LlNAC014 was a direct regulator of the DREB2-HSFA3 module, and bound to the CTT(N7)AAG element in the promoters of LlHSFA3A , LlHSFA3B , and LlDREB2B to activate their expression. Thus, LlNAC014 increased thermotolerance by sensing high temperature and translocating to the nucleus to activate the DREB2-HSFA3 module. [ABSTRACT FROM AUTHOR]

HD-Zip I transcription factors play important roles in plant development and response to abiotic stresses; however, their roles in thermotolerance are largely unknown. Through transcriptome analysis in lily (Lilium longiflorum), we isolated and identified a HD-Zip I gene differentially expressed at high temperatures, LlHB16 , which belongs to the β2 subgroup and positively regulates thermotolerance. The expression of LlHB16 was rapidly and continuously activated by heat stress. LlHB16 protein localized to the nucleus and exhibited transactivation activity in both plant and yeast cells, and its C-terminus contributed to its transcriptional activity. Overexpressing LlHB16 in Arabidopsis and lily improved thermotolerance and activated the expression of heat-related genes in both plants, especially that of HSFA2 and MBF1c. In addition, LlHB16 overexpression in Arabidopsis also caused growth defects, delayed flowering and abscisic acid (ABA) insensitivity. Further analysis revealed that LlHB16 directly binds to the promoters of LlHSFA2 and LlMBF1c and activates their expressions. Similarly, the expression of AtHSFA2 and AtMBF1c was also elevated in LlHB16 transgenic Arabidopsis lines. Together, our findings demonstrate that LlHB16 participates in the establishment of thermotolerance involved in activating LlHSFA2 and LlMBF1c , and LlHB16 overexpression resulted in ABA insensitivity in transgenic plants, suggesting that LlHB16 links the basal heat-responsive pathway and ABA signal to collaboratively regulate thermotolerance. [ABSTRACT FROM AUTHOR]

Pollination niche shifts can drive remarkable floral divergence between closely related plant species. The Leucolirion clade of Lilium contains species with either tepal-recurved or trumpet-shaped flowers. The tepal-recurved flowers are bright orange and might be pollinated by butterflies and/or birds. The trumpet-shaped flowers are mostly pale and strongly fragrant and might permit visitation by a variety of hawkmoths. Lilium leucanthum has trumpet-shaped flowers, and some populations of this species show dark coloration on the floral outer surface, suggesting pollination by mammals. We identified pollinators and examined the dependence of reproduction on pollinators by floral visitor observations, pollen load analysis and pollination experiments. We also analysed floral traits to contrast the two floral syndromes involving different lepidopteran groups. The tepal-recurved lilies are specialized on a group of Papilio butterflies for pollination with pollen predominantly attached to the hindwings. The trumpet-shaped flowers are almost exclusively pollinated by hawkmoths, including diverse species with proboscises of different lengths. No mammal visitation was found to the populations of L. leucanthum with dark outer surfaces of flowers. Self-incompatibility prevails throughout the clade, including the populations in which pollinators were scarce. The butterfly- and hawkmoth-pollinated species display contrasting floral syndromes. Our findings confirmed that the dichotomy in floral syndrome in the Leucolirion clade is associated with Papilio butterfly vs. hawkmoth pollination, whereas intraspecific variation in colour of the floral outer surface of L. leucanthum many need a non-pollinator explanation. [ABSTRACT FROM AUTHOR]

While book-piracy is often thought of as an Elizabethan problem, the organized infringement of lucrative copyrights in fact began a few decades earlier, in the reign of Mary Tudor. In this paper the known details are presented of what are probably the two best documented cases from that reign. The first was the repeated commissioning and importation of editions of Lily's Grammar from Geneva (some of them falsely dated). The second was the reprinting of a collection of sermons whose authorized printer had secured a patent to protect it. In the first case the patentee's attempts to obtain satisfaction in Chancery were unsuccessful; in the second the author's interests fared rather better in Star Chamber, and may thus have established a precedent for the prosecution of Elizabethan pirates. [ABSTRACT FROM AUTHOR]

Liliaceae, distributed mainly across the temperate Northern Hemisphere, are of great horticultural, culinary and medical importance, but are also a family with a long history of taxonomic uncertainty. Challenges in accurate species identification persist and phylogenetic relationships among genera in the family continue to be unresolved and/or weakly supported due to the use of limited molecular markers with insufficient variability. Here, nine newly sequenced plastomes for nine Liliaceae genera have been combined with previously published plastome data for this family, providing a total of 86 complete plastid genome sequences covering all 15 currently recognized genera for analyses. All these plastid genomes (146.9–158.3 kb) possess the typical quadripartite structure with conserved genome arrangement and content. Phylogenomic analyses strongly confirm the recognition of four subfamilies: Tricyrtidoideae with four genera; Medeoloideae with two genera; Lilioideae with eight genera and Calochortoideae, for Calochortus alone, as sister to Medeoloideae and Lilioideae. At least ten intergenic spacer regions that may serve as universal markers were identified in the family and, on a finer scale, nine and seven intergenic spacer regions are especially variable in Lilium and Fritillaria , respectively. The intergenic spacer regions rpoB - trnC , trnS - trnG , trnT - psbD and trnT - trnL , which showed high phylogenetic effectiveness, may be the best choices for future phylogenetic, phylogeographic and population genetic studies. [ABSTRACT FROM AUTHOR]

Aims: One of the strategies to combat antibiotic resistance can be the use of plant materials in combination with antibiotics, taking into account that phytochemicals can act as antibiotic resistance‐modifying agents. This can give a second life to the traditional antibiotics. The aim was to evaluate antibiotic modulatory effect of crude extracts from Agrimonia eupatoria, Hypericum alpestre, Rumex obtusifolius and Sanguisorba officinalis herbs towards several commercial antibiotics using some Gram‐positive and Gram‐negative bacteria. Methods: The antibiotic modulatory activity was tested by determining MICs of antibiotics in the absence and presence of plant crude extracts at subinhibitory concentrations. Antiviral potential of different extracts of tested plant materials was also explored by double overlay plaque assay. Results: The tested plant crude extracts exhibited high modulatory activity towards used antibiotics. Particularly, high modulatory activity was observed with extracts of H. alpestre and R. obtusifolius. Many plant‐antibiotic combinations induced the decrease in MICs of antibiotics up to ~fourfold indicating synergy. Moreover, the similar change was observed at both subinhibitory concentrations (MIC/2 and MIC/4) of the same plant crude extract. High anti‐phage activity of plants with the exception of Lilium armenum against T4 phage of Escherichia coli C‐T4 was also shown. Conclusions: Plant crude extract or commercial antibiotic combinations significantly increased the efficiency of antibiotics. Tested plant materials with exception of L. armenum have antiviral property. Significance and Impact of the Study: For the first time, antibiotic modulatory activity of tested herb extracts was shown, which could have potential in practical applications. Tested plant materials with exception of L. armenum could have prospective, as a source of new antiviral compounds. [ABSTRACT FROM AUTHOR]

Lilium×formolongi is a facultative long-day (LD) plant. Aiming to dissect the molecular regulation of the photoperiodic pathway, largely unknown in Lilium, we explored the CONSTANS / FLOWERING LOCUS T (CO/FT) module, a major regulatory factor in the external coincidence model of the photoperiodic flowering pathway in lily. We identified eight CONSTANS-LIKE (COL) family members in L.×formolongi, which could be divided into three types, according to their zinc-finger (B-box) protein domains. Type I included only LfCOL5, containing two B-box motifs. Type II contained six LfCOLs members that had only one B-box motif. Type III contained only LfCOL9 that showed a normal B-box and a second divergent B-box motif. Phylogenic analyses revealed that LfCOL5 was the closest to Arabidopsis CO. LfCOL 5, LfCOL6 and LfCOL9 were up-regulated at the flowering induction stage under LDs, coinciding with an increase in LfFT1 expression. LfCOL5, LfCOL6 and LfCOL9 also showed obvious diurnal expression pattern for 3 d under LDs. However, under short-day (SD) conditions, the expression patterns of LfCOL5, LfCOL6 and LfCOL9 were variable and complex, with regard to the developmental stages and circadian rhythm. LfCOL5, LfCOL6 and LfCOL9 complemented the late flowering phenotype of the co mutant in Arabidopsis. Taken together, the results suggest that LfCOL5, LfCOL6 and LfCOL9 are involved in triggering flowering induction under LDs. LfCOL6 and LfCOL9 belong to types different from functional COL homologs in other plant species, illustrating the variation in phylogeny, evolution and gene function among LfCOL family members. [ABSTRACT FROM AUTHOR]

Epigenetic variation in natural populations with contrasting habitats might be an important element, in addition to the genetic variation, in plant adaptation to environmental stress. Here, we assessed genetic, epigenetic, and cytogenetic structure of the three Lilium bosniacum populations growing on distinct habitats. One population was growing under habitual ecological conditions for this species and the other two were growing under stress associated with high altitude and serpentine soil. Amplified fragment length polymorphism and methylation-sensitive amplification polymorphism analyses revealed that the three populations did not differentiate genetically, but were clearly separated in three distinct clusters according to DNA methylation profiles. Principal coordinate analysis showed that overall epigenetic variation was closely related to habitat conditions. A new methylation-sensitive amplification polymorphism scoring approach allowed identification of mainly unmethylated (ΦST=0.190) and fully CpG methylated (ΦST=0.118) subepiloci playing a role in overall population differentiation, in comparison with hemimethylated sites (ΦST=0.073). In addition, unusual rDNA repatterning and the presence of B chromosomes bearing 5S rDNA loci were recorded in the population growing on serpentine soil, suggesting dynamic chromosome rearrangements probably linked to global genome demethylation, which might have reactivated some mobile elements. We discuss our results considering our earlier data on morphology and leaf anatomy of several L. bosniacum populations, and suggest a possible role of epigenetics as a key element in population differentiation associated with environmental stress in these particular lily populations. [ABSTRACT FROM AUTHOR]

Three larval parasitoids were imported from Europe to control the lily leaf beetle, Lilioceris lilii Scopoli (Coleoptera: Chrysomelidae), an accidentally introduced herbivore of native and cultivated lilies in North America. Tetrastichus setifer Thomson (Hymenoptera: Eulophidae) was introduced in Massachusetts in 1999, and was found to be established there in 2002. Subsequent releases of T. setifer were made and two additional parasitoids, Lemophagus errabundus Szepligeti (Hymenoptera: Ichneumonidae) and Diaparsis jucunda (Holmgren) (Hymenoptera: Ichneumonidae), were introduced. The establishment and distribution of the three parasitoids was evaluated through 2016. Tetrastichus setifer is now established in Massachusetts, Rhode Island, New Hampshire, Maine, Connecticut, and Ontario, Canada. Lemophagus errabundus is established in Massachusetts and Rhode Island, and D. jucunda is established in Massachusetts, Rhode Island, Connecticut, and Maine. All three parasitoids have spread at least 10km from release sites. The establishment of T. setifer is associated with a substantial reduction of L. lilii. In time it is likely that the parasitoids will spread throughout the North American range of L. lilii. This process can be accelerated to protect ornamental and native lilies by collecting and redistributing parasitoids to new infestations of L. lilii. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis and organogenesis inLilium pumilumwere successfully regulated by picloram, ?-naphthaleneacetic acid (NAA), and 6-benzyladenine (BA). In organogenesis, the highest shoot regeneration frequency (92.5%) was obtained directly from bulb scales on Murashige and Skoog (MS) medium containing 2.0 mg L?1BA and 0.2 mg L?1NAA, while organogenic callus (OC) formed from leaves on MS medium supplemented with 1.0 mg L?1BA and 0.5 mg L?1NAA. Following subculture, 76.7% of OC regenerated shoots. In somatic embryogenesis, the combination of picloram and NAA increased the amount of embryogenic callus (EC) that formed with a maximum on 90.7% of all explants which formed 11 somatic embryos (SEs) per explant. Differences between EC and OC in cellular morphology and cell differentiation fate were easily observed. SEs initially formed via an exogenous or an endogenous origin. The appearance of a protoderm in heart-shaped SE and the bipolar shoot–root development in oval-shaped SE indicated true somatic embryogenesis. This protocol provides a new and detailed regulation and histological examination of regeneration pattern inL. pumilum. Regulation and histological examination of somatic embryogenesis and organogenesis inLilium pumilum. [ABSTRACT FROM PUBLISHER]

Flowering plants typically use floral rewards to attract animal pollinators. Unlike nectar, pollen rewards are usually visible and may thus function as a signal that influences landing decisions by pollen-seeking insects. Here we artificially manipulate the presence of both pollen and staminal hairs (a putative false signal of pollen reward availability) in the hermaphroditic lily Bulbine abyssinica ( Xanthorrhoeaceae) to investigate their effects on bee visitation and fecundity, and also test for trade-offs between pollen production and seed production. Honeybees, the primary floral visitors, are probably not able to distinguish between colours of petals, staminal hairs and pollen of B. abyssinica, according to analysis of reflectance spectra in a bee vision model. Flowers with both pollen and hairs removed had the lowest levels of bee visitation, seed set and seed abortions. Flowers containing hairs had an ∼50% increase in visitation rate and seed set compared with emasculated flowers, while intact controls had the highest seed abortion rate. Ovule discounting in intact flowers is probably due to ovarian self-incompatibility (or strong early inbreeding depression) as ovules penetrated by tubes from self-pollen uniformly failed to develop into seeds. These results show that staminal hairs can enhance plant fecundity by increasing attraction of pollen-seeking insects to flowers without increasing the risk of ovule discounting through pollinator-mediated self-pollination. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177, 481-490. [ABSTRACT FROM AUTHOR]

A literary criticism of the English novel "Clarissa" by Samuel Richardson is presented. The author discusses the symbol of the broken lily and traces its source to the Spanish emblem book by Sebastian de Covarrubias Orozco, as well as the appearance of other emblems on funeral monuments in England.

In lily (Lilium formosanum) pollen tubes, pectin, a major component of the cell wall, is delivered through regulated exocytosis. The targeted transport and secretion of the pectin-containing vesicles may be controlled by the cortical actin fringe at the pollen tube apex. Here, we address the role of the actin fringe using three different inhibitors of growth: brefeldin A, latrunculin B, and potassium cyanide. Brefeldin A blocks membrane trafficking and inhibits exocytosis in pollen tubes; it also leads to the degradation of the actin fringe and the formation of an aggregate of filamentous actin at the base of the clear zone. Latrunculin B, which depolymerizes filamentous actin, markedly slows growth but allows focused pectin deposition to continue. Of note, the locus of deposition shifts frequently and correlates with changes in the direction of growth. Finally, potassium cyanide, an electron transport chain inhibitor, briefly stops growth while causing the actin fringe to completely disappear. Pectin deposition continues but lacks focus, instead being delivered in a wide arc across the pollen tube tip. These data support a model in which the actin fringe contributes to the focused secretion of pectin to the apical cell wall and, thus, to the polarized growth of the pollen tube. [ABSTRACT FROM AUTHOR]

Background and Aims Variation in the relative female and male reproductive success of flowering plants is widespread, despite the fundamental hermaphroditic condition of the majority of species. In many hermaphroditic populations, environmental conditions and their influence on development and size can influence the gender expression of individuals through the formation of hermaphroditic and unisexual flowers. This study investigates the hypothesis that the bulbous, animal-pollinated, perennial Lilium apertum (Liliaceae) exhibits a form of size-dependent gender modification known as gender diphasy, in which the sexual expression of individuals depends on their size, with plants often changing sex between seasons. Methods Variation in floral traits was examined in relation to their size using marked individuals in natural populations, and also under glasshouse conditions. Measurements were taken of the height, flower number, floral sex expression, flower size, flower biomass and pollen production of individuals over consecutive years between 2009 and 2012 in seven populations in south-west China. Key Results Flowers of L. apertum are either perfect (hermaphroditic) or staminate (male) and, in any given season, plants exhibit one of three sex phenotypes: only hermaphrodite flowers, a mixture of hermaphroditic and male flowers, or only male flowers. Transitions between each of these sex phenotypes were observed over consecutive years and were commonly size-dependent, particularly transitions from small plants bearing only male flowers to those that were taller with hermaphroditic flowers. Hermaphroditic flowers were significantly larger, heavier and produced more pollen than male flowers. Conclusions The results for L. apertum are consistent with the ‘size advantage hypothesis’ developed for animal species with sex change. The theory predicts that when individuals are small they should exhibit the sex for which the costs of reproduction are less, and this usually involves the male phase. L. apertum provides an example of gender diphasy, a rare sexual system in flowering plants. [ABSTRACT FROM AUTHOR]

The orange color of tiger lily (Lolium lancifolium ‘Splendens’) flowers is due, primarily, to the accumulation of two κ-xanthophylls, capsanthin and capsorubin. An enzyme, known as capsanthin-capsorubin synthase (CCS), catalyzes the conversion of antheraxanthin and violaxanthin into capsanthin and capsorubin, respectively. We cloned the gene for capsanthin-capsorubin synthase (Llccs) from flower tepals of L. lancifolium by the rapid amplification of cDNA ends (RACE) with a heterologous non-degenerate primer that was based on the sequence of a gene for lycopene β-cyclase (lcyB). The full-length cDNA of Llccs was 1,785 bp long and contained an open reading frame of 1,425 bp that encoded a polypeptide of 474 amino acids with a predicted N-terminal plastid-targeting sequence. Analysis by reverse transcription–PCR (RT–PCR) revealed that expression of Llccs was spatially and temporally regulated, with expression in flower buds and flowers of L. lancifolium but not in vegetative tissues. Stable overexpression of the Llccs gene in callus tissue of Iris germanica, which accumulates several xanthophylls including violaxanthin, the precursor of capsorubin, resulted in transgenic callus whose color had changed from its normal yellow to red-orange. This novel red-orange coloration was due to the accumulation of two non-native κ-xanthophylls, capsanthin and capsorubin, as confirmed by HPLC and ultraperformance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS) analysis with authentic standards. Cloning of the Llccs gene should advance our understanding of the molecular and genetic mechanisms of the biosynthesis of κ-carotenoids in general and in the genus Lilium in particular, and will facilitate transgenic alterations of the colors of flowers and fruits of many plant species. [ABSTRACT FROM AUTHOR]

An actin fringe structure in the subapex plays an important role in pollen tube tip growth. However, the precise mechanism by which the actin fringe is generated and maintained remains largely unknown. Here, we cloned a 2606-bp full-length cDNA encoding a deduced 77-kD fimbrin-like protein from lily (Lilium longiflorum), named FIMBRIN1 (FIM1). Ll-FIM1 was preferentially expressed in pollen and concentrated at actin fringe in the subapical region, as well as in longitudinal actin-filament bundles in the shank of pollen tubes. Microinjection of Ll-FIM1 antibody into lily pollen tubes inhibited tip growth and disrupted the actin fringe. Furthermore, we verified the function of Ll-FIM1 in the fim5 mutant of its closest relative, Arabidopsis thaliana. Pollen tubes of fim5 mutants grew with a larger diameter in early stages but could recover into normal forms in later stages, despite significantly slower growth rates. The actin fringe of the fim5 mutants, however, was impaired during both early and late stages. Impressively, stable expression of fim5pro : GFP : Ll-FIM1 rescued the actin fringe and the growth rate of Arabidopsis fim5 pollen tubes. In vitro biochemical analysis showed that Ll-FIM1 could bundle actin filaments. Thus, our study has identified a fimbrin that may stabilize the actin fringe by cross-linking actin filaments into bundles, which is important for proper tip growth of lily pollen tubes. [ABSTRACT FROM AUTHOR]

Although exogenous ABA-regulated heterophylly has been well documented in multiple plant species, the effect of endogenous ABA and its molecular mechanism remain uncharacterized. In the present study, the effects of endogenous ABA on heterophyllous switching were investigated in two different lily varieties, Lilium formosanum and Lilium oriental hybrid ‘Casa Blanca’. Seedlings of L. formosanum, which have scale-leaf-type growth, displayed low levels of both 9-cis-epoxycarotenoid dioxygenase 3 (LfNCED3) transcripts and ABA, whereas seedlings of L. oriental hybrid ‘Casa Blanca’, which have scale-type growth, displayed high levels of both LoNCED3 transcripts and ABA. Sucrose induced endogenous ABA production in cultured lilies; low ABA induction shows scale-leaf-type growth, whereas scale-type growth becomes predominant when ABA levels are high. Heterologous expression of either LfNCED3 or LoNCED3 was found to complement the Arabidopsis Atnced3 mutant. Interestingly, the expression patterns of LfNCED3 and LoNCED3 in transgenic Arabidopsis plants are distinguishable. Further promoter analysis revealed that a putative E2F-like element in the LfNCED3 promoter, but not in the LoNCED3 promoter, plays a negative role in controlling its activity. Collectively, our results demonstrate that NCED3 plays a key role in ABA-mediated heterophylly in lilies. [ABSTRACT FROM AUTHOR]

To allow successful germination and growth of a pollen tube, mature and dehydrated pollen grains (PGs) take up water and have to adjust their turgor pressure according to the water potential of the surrounding stigma surface. The turgor pressure of PGs of lily (Lilium longiflorum) was measured with a modified pressure probe for simultaneous recordings of turgor pressure and membrane potential to investigate the relation between water and electrogenic ion transport in osmoregulation. Upon hyperosmolar shock, the turgor pressure decreased, and the plasma membrane (PM) hyperpolarizes in parallel, whereas depolarization of the PM was observed with hypoosmolar treatment. An acidification and alkalinization of the external medium was monitored after hyper- and hypoosmotic treatments, respectively, and pH changes were blocked by vanadate, indicating a putative role of the PM H+ ATPase. Indeed, an increase in PM-associated 14-3-3 proteins and an increase in PM H+ ATPase activity were detected in PGs challenged by hyperosmolar medium. We therefore suggest that in PGs the PM H+ ATPase via modulation of its activity by 14-3-3 proteins is involved in the regulation of turgor pressure. [ABSTRACT FROM AUTHOR]

Anthocyanins are secondary metabolites that contribute to colors of flowers, fruits and leaves. Asiatic hybrid lily (Lilium spp.) accumulates cyanidin anthocyanins in flower tepals, tepal spots and leaves of juvenile shoots. To clarify their mechanisms of regulation of anthocyanin pigmentation, two full-length cDNAs of R2R3-MYB (LhMYB6 and LhMYB12) were isolated from the anthocyanin-accumulating tepals of cultivar ‘Montreux’. Analysis of the deduced amino acid sequences indicated they have homology with petunia AN2, homologous sequences of which had not been isolated in species of monocots. Yeast two-hybrid analysis showed that LhMYB6 and LhMYB12 interacted with the Lilium hybrid basic helix–loop–helix 2 (LhbHLH2) protein. Transient expression analysis indicated that co-expression of LhMYB6 and LhbHLH2 or LhMYB12 and LhbHLH2, introduced by a microprojectile, activated the transcription of anthocyanin biosynthesis genes in lily bulbscales. Spatial and temporal transcription of LhMYB6 and LhMYB12 was analyzed. The expression of LhMYB12 corresponded well with anthocyanin pigmentation in tepals, filaments and styles, and that of LhMYB6 correlated with anthocyanin spots in tepals and light-induced pigmentation in leaves. These results indicate that LhMYB6 and LhMYB12 positively regulate anthocyanin biosynthesis and determine organ- and tissue-specific accumulation of anthocyanin. [ABSTRACT FROM PUBLISHER]

The nucleotide sequences of regulatory elements from homologous genes can be strongly divergent. Phylogenetic footprinting, a comparative analysis of noncoding regions, can detect putative transcription factor binding sites (TFBSs) shared among the regulatory regions of 2 or more homologous genes. These conserved motifs have the potential to serve the same regulatory function in distantly related taxa. We isolated the 5′-noncoding region of the OrcPI gene, a MADS-box transcription factor involved in flower development in Orchis italica, using the thermal asymmetric interlaced polymerase chain reaction technique. This region (comprising 1352 bp) induced transient β-glucuronidase expression in the petal tissue of white Rosa hybrida flowers and represents the 5′-regulatory sequence of the OrcPI gene. Phylogenetic footprinting analysis detected conserved regions within the 5′-regulatory sequence of OrcPI and the homologous regions of Oryza sativa, Lilium regale, and Arabidopsis thaliana. Some of these sequences are known TFBSs described in databases of plant regulatory elements. Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the following accession numbers: AF198055 promoter region of the PISTILLATA (PI) gene of A. thaliana; AB094985 cDNA of OrcPI (PI/GLOBOSA [PI/GLO] homologue) of O. italica; AB378089 5′-regulatory region of the OrcPI gene of O. italica; AP008211 putative promoter region of OSMADS2 (PI/GLO homologue) of O. sativa; AP008207 putative promoter region of OSMADS4 (PI/GLO homologue) of O. sativa; and AB158292 putative promoter region of the PI/GLO homologue of L. regale. [ABSTRACT FROM PUBLISHER]

During compatible pollination of the angiosperms, pollen tubes grow in the pistil transmitting tract (TT) and are guided to the ovule for fertilization. Lily (Lilium longiflorum) stigma/style Cys-rich adhesin (SCA), a plant lipid transfer protein (LTP), is a small, secreted peptide involved in pollen tube adhesion-mediated guidance. Here, we used a reverse genetic approach to study biological roles of Arabidopsis thaliana LTP5, a SCA-like LTP. The T-DNA insertional gain-of-function mutant plant for LTP5 (ltp5-1) exhibited ballooned pollen tubes, delayed pollen tube growth, and decreased numbers of fertilized eggs. Our reciprocal cross-pollination study revealed that ltp5-1 results in both male and female partial sterility. RT-PCR and β-glucuronidase analyses showed that LTP5 is present in pollen and the pistil TT in low levels. Pollen-targeted overexpression of either ltp5-1 or wild-type LTP5 resulted in defects in polar tip growth of pollen tubes and thereby decreased seed set, suggesting that mutant ltp5-1 acts as a dominant-active form of wild-type LTP5 in pollen tube growth. The ltp5-1 protein has additional hydrophobic C-terminal sequences, compared with LTP5. In our structural homology/molecular dynamics modeling, Tyr-91 in ltp5-1, replacing Val-91 in LTP5, was predicted to interact with Arg-45 and Tyr-81, which are known to interact with a lipid ligand in maize (Zea mays) LTP. Thus, Arabidopsis LTP5 plays a significant role in reproduction. [ABSTRACT FROM AUTHOR]

We examined exocytosis during oscillatory growth in lily (Lilium formosanum and Lilium longiflorum) and tobacco (Nicotiana tabacum) pollen tubes using three markers: (1) changes in cell wall thickness by Nomarski differential interference contrast (DIC), (2) changes in apical cell wall fluorescence in cells stained with propidium iodide (PI), and (3) changes in apical wall fluorescence in cells expressing tobacco pectin methyl esterase fused to green fluorescent protein (PME-GFP). Using PI fluorescence, we quantified oscillatory changes in the amount of wall material from both lily and tobacco pollen tubes. Measurement of wall thickness by DIC was only possible with lily due to limitations of microscope resolution. PME-GFP, a direct marker for exocytosis, only provides information in tobacco because its expression in lily causes growth inhibition and cell death. We show that exocytosis in pollen tubes oscillates and leads the increase in growth rate; the mean phase difference between exocytosis and growth is -98° ± 3° in lily and -124° ± 4° in tobacco. Statistical analyses reveal that the anticipatory increase in wall material predicts, to a high degree, the rate and extent of the subsequent growth surge. Exocytosis emerges as a prime candidate for the initiation and regulation of oscillatory pollen tube growth. [ABSTRACT FROM AUTHOR]

ABP41 is identified as a novel member of plant villin/gelsolin/fragmin superfamily proteins from lily pollen, which binds stoichiometrically to actin filaments and severs them in vitro. To further understand its in-vivo function and the potential molecular mechanisms, biochemical analysis, fluorescence microscopic observation and microinjection assays were performed. Different biochemical measurements showed that ABP41 maintained actin filaments in forms of short F-actin in vitro. Microinjection of ABP41 into pollen tubes could fragment the pre-existing actin filaments, inhibit the velocity of cytoplasmic streaming, and shorten the length of the clear zone of pollen tube. In addition, it was found that the endogenous ABP41 expressing level was dynamically corresponding to the short actin filament structure in pollen at different stages of pollen germination. Our results suggest that ABP41 is involved in the regulation of actin dynamics during the pollen germination process via maintenance of short dynamic actin filaments. [ABSTRACT FROM PUBLISHER]

Villin/gelsolin/fragmin superfamily proteins have been shown to function in tip-growing plant cells. However, genes encoding gelsolin/fragmin do not exist in the Arabidopsis thaliana and rice (Oryza sativa) databases, and it is possible that these proteins are encoded by villin mRNA splicing variants. We cloned a 1006-bp full-length cDNA from Lilium Iongiflorum that encodes a 263-amino acid predicted protein sharing 100% identity with the N terminus of 135-ABP (Lilium villin) except for six C-terminal amino acids. The deduced 29-kD protein, Lilium ACTIN BINDING PROTEIN29 (ABP29), contains only the G1 and G2 domains and is the smallest identified member of the villin/gelsolin/fragmin superfamily. The purified recombinant ABP29 accelerates actin nucleation, blocks barbed ends, and severs actin filaments in a Ca2+- and/or phosphatidylinositol 4,5-bisphosphate-regulated manner in vitro. Microinjection of the protein into stamen hair cells disrupted transvacuolar strands whose backbone is mainly actin filament bundles. Transient expression of ABP29 by microprojectile bombardment of lily pollen resulted in actin filament fragmentation and inhibited pollen germination and tube growth. Our results suggest that ABP29 is a splicing variant of Lilium villin and a member of the villin/gelsolin/fragmin superfamily, which plays important roles in rearrangement of the actin cytoskeleton during pollen germination and tube growth. [ABSTRACT FROM AUTHOR]

Alstroemeria (Liliales) has two layers of petaloid tepals, in which the often spotted narrow inner tepals can be distinguished easily from the wider outer tepals. In order to explore this floral morphology in Alstroemeria, we investigated the tepal morphology and the expression patterns of three class B genes, whose homologs in eudicots have been shown previously to be involved in petal and stamen development. The two DEF-like genes (AlsDEFa and AlsDEFb) and the one GLO-like gene (AlsGLO) of Alstroemeria ligtu were isolated by rapid amplification of cDNA ends (RACE). Northern hybridization, reverse transcription–PCR (RT–PCR) and in situ hybridization analyses indicated that AlsDEFb and AlsGLO were expressed in whorls 1, 2 and 3 (outer tepals, inner tepals and stamens, respectively), whereas AlsDEFa expression was detected only in whorls 2 and 3. These results suggest that in A. ligtu, AlsDEFb and AlsGLO would participate in determining the organ identity of the two-layered petaloid tepals and stamens, which is in support of the modified ABC model. Additionally, the distinctive expression patterns of AlsDEFa and AlsDEFb might be related to morphological differences between the two-layered tepals. [ABSTRACT FROM AUTHOR]

The location and changes in NAD(P)H have been monitored during oscillatory growth in pollen tubes of lily (Lilium formosanum) using the endogenous fluorescence of the reduced coenzyme (excitation, 360 nm; emission, >400 nm). The strongest signal resides 20 to 40 μm behind the apex where mitochondria (stained with Mitotracker Green) accumulate. Measurements at 3-s intervals reveal that NAD(P)H-dependent fluorescence oscillates during oscillatory growth. Cross-correlation analysis indicates that the peaks follow growth maxima by 7 to 11 s or 77° to 116°, whereas the troughs anticipate growth maxima by 5 to 10 s or 54° to 107°. We have focused on the troughs because they anticipate growth and are as strongly correlated with growth as the peaks. Analysis of the signal in 10-μm increments along the length of the tube indicates that the troughs are most advanced in the extreme apex. However, this signal moves basipetally as a wave, being in phase with growth rate oscillations at 50 to 60 μm from the apex. We suggest that the changes in fluorescence are due to an oscillation between the reduced (peaks) and oxidized (troughs) states of the coenzyme and that an increase in the oxidized state [NAD(P)+] may be coupled to the synthesis of ATP. We also show that diphenyleneiodonium, an inhibitor of NAD(P)H dehydrogenases, causes an increase in fluorescence and a decrease in tube growth. Finally, staining with 5-(and-6)-chloromethyl-2′,7′ -dichlorohydrofluorescein acetate indicates that reactive oxygen species are most abundant in the region where mitochondria accumulate and where NAD(P)H fluorescence is maximal. [ABSTRACT FROM AUTHOR]

Pollen tube adhesion and guidance on extracellular matrices within the pistil are essential processes that convey the pollen tube cell and the sperm cells to the ovule. In this study, we purified an additional molecule from the pistil that enhances pollen tube adhesion when combined with the SCA (stigma/stylar cysteine-rich adhesin)/pectin matrix in our in vitro assay. The enhancer of adhesion was identified as free ubiquitin (Ub). This was confirmed by use of bovine Ub as a substitute for lily (Lilium longiflorum Thunb.) stigma Ub. To study the interaction of SCA and Ub with the lily pollen tube, we labeled both proteins with biotin. We observed uptake of biotin-labeled SCA and Ub into the pollen tube cells in vitro using confocal microscopy. For SCA, a strong signal occurred first at the tip of the pollen tube, suggestive of an endocytosis event, and then progressively throughout the tube cytoplasm. SCA was also localized inside the in vivo pollen tube using immunogold electron microscopy and found to be present in endosomes, multivesicular bodies, and vacuoles, all known to be endocytic compartments. It was also confirmed that SCA is endocytosed in the in vitro adhesion assay. Internalization of SCA was increased in pollen tubes treated with exogenous Ub compared to those without Ub, suggesting that Ub may facilitate SCA endocytosis. These results show that Ub can act as an enhancer of pollen tube adhesion in vitro and that it is taken up into the pollen tube as is SCA. The Ub machinery may play a role in pollen tube adhesion and guidance in lily. [ABSTRACT FROM AUTHOR]

Lily (Lilium fonmosanum or Lilium longiflorum) pollen tubes, microinjected with a low concentration of the pH-sensitive dye bis-carboxyethyl carboxyfluorescein dextran, show oscillating pH changes in their apical domain relative to growth. An increase in pH in the apex precedes the fastest growth velocities, whereas a decline follows growth, suggesting a possible relationship between alkalinity and cell extension. A target for pH may be the actin cytoskeleton, because the apical cortical actin fringe resides in the same region as the alkaline band in lily pollen tubes and elongation requires actin polymerization. A pH-sensitive actin binding protein, actin-depolymerizing factor (ADF), together with actin-interacting protein (ALP) localize to the cortical actin fringe region. Modifying intracellular pH leads to reorganization of the actin cytoskeleton, especially in the apical domain. Acidification causes actin filament destabilization and inhibits growth by 80%. Upon complete growth inhibition, the actin fringe is the first actin cytoskeleton component to disappear. We propose that during normal growth, the pH increase in the alkaline band stimulates the fragmenting activity of ADF/AIP, which in turn generates more sites for actin polymerization. Increased actin polymerization supports faster growth rates and a proton influx, which inactivates ADF/AIP, decreases actin polymerization, and retards growth. As pH stabilizes and increases, the activity of ADF/AIP again increases, repeating the cycle of events. [ABSTRACT FROM AUTHOR]

Differences in level of herbivory can select for local adaptation and genetic differentiation of plant populations in different environments. Mean bulb depth of the desert lily Pancratium sickenbergeri, differs considerably among populations differing in the level of herbivory by the dorcas gazelle. The gazelle digs in the sand to remove most of die bulb of the lily. Deeper bulbs have less material removed by herbivory than shallow bulbs and have higher fitness. A possible confounding factor is the degree of sand compaction, which may retard the downward growth of the bulb. We conducted a common garden experiment with 2 sand types with seeds from source populations with different levels of herbivory. There was a large genetic difference among populations. Two of 3 analyses indicated that there was an interaction between population and sand type, indicating that there is a heritable component of plasticity. [ABSTRACT FROM AUTHOR]

From germinating pollen of lily, two types of villins, P-115-ABP and P-135-ABP, have been identified biochemically. Ca2+-CaM-dependent actin-filament binding and bundling activities have been demonstrated for both villins previously. Here, we examined the effects of lily villins on the polymerization and depolymerization of actin. P-115-ABP and P-135-ABP present in a crude protein extract prepared from germinating pollen bound to a DNase I affinity column in a Ca2+-dependent manner. Purified P-135-ABP reduced the lag period that precedes actin filament polymerization from monomers in the presence of either Ca2+ or Ca2+-CaM. These results indicated that P-135-ABP can form a complex with G-actin in the presence of Ca2+ and this complex acts as a nucleus for polymerization of actin filaments. However, the nucleation activity of P-135-ABP is probably not relevant in vivo because the assembly of G-actin saturated with profilin, a situation that mimics conditions found in pollen, was not accelerated in the presence of P-135-ABP. P-135-ABP also enhanced the depolymerization of actin filaments during dilution-mediated disassembly. Growth from filament barbed ends in the presence of Ca2+-CaM was also prevented, consistent with filament capping activity. These results suggested that lily villin is involved not only in the arrangement of actin filaments into bundles in the basal and shank region of the pollen tube, but also in regulating and modulating actin dynamics through its capping and depolymerization (or fragmentation) activities in the apical region of the pollen tube, where there is a relatively high concentration of Ca2+. [ABSTRACT FROM AUTHOR]

The phosphatidylinositol-specific phospholipase C (PI-PLC) activity is detected in purified Lilium pollen protoplasts. Two PI-PLC full length cDNAs, LdPLC1 and LdPLC2, were isolated from pollen of Lilium daviddi. The amino acid sequences for the two PI-PLCs deduced from the two cDNA sequences contain X, Y catalytic motifs and C2 domains. Blast analysis shows that LdPLCs have 60–65% identities to the PI-PLCs from other plant species. Both recombinant PI-PLCs proteins expressed in E. coli cells show the PIP2-hydrolyzing activity. The RT-PCR analysis shows that both of them are expressed in pollen grains, whereas expression level of LdPLC2 is induced in germinating pollen. The exogenous purified calmodulin (CaM) is able to stimulate the activity of the PI-PLC when it is added into the pollen protoplast medium, while anti-CaM antibody suppresses the stimulation effect caused by exogenous CaM. PI-PLC activity is enhanced by G protein agonist cholera toxin and decreased by G protein antagonist pertussis toxin. Increasing in PI-PLC activity caused by exogenous purified CaM is also inhibited by pertussis toxin. A PI-PLC inhibitor, U-73122, inhibited the stimulation of PI-PLC activity caused by cholera toxin and it also leads to the decrease of [Ca2+]cyt in pollen grains. Those results suggest that the PPI-PLC signaling pathway is present in Liliumdaviddi pollen, and PI-PLC activity might be regulated by a heterotrimeric G protein and extracellular CaM. [ABSTRACT FROM AUTHOR]

LLA23, an abscisic acid-, stress-, and ripening-induced protein, was previously isolated from lily (Lilium longiflorum) pollen. The expression of LLA23 is induced under the application of abscisic acid (ABA), NaCl, or dehydration. To provide evidence on the biological role of LLA23 proteins against drought, we used an overexpression approach in Arabidopsis (Arabidopsis thaliana). Constitutive overexpression of LLA23 under the cauliflower mosaic virus 35S promoter confers reduced sensitivity to ABA in Arabidopsis seeds and, consequently, a reduced degree of seed dormancy. Transgenic 35S::LLA23 seeds are able to germinate under unfavorable conditions, such as inhibitory concentrations of mannitol and NaCl. At the molecular level, altered expression of ABA/stress-regulated genes was observed. Thus, our results provide strong in vivo evidence that LLA23 mediates stress-responsive ABA signaling. In vegetative tissues, it is intriguing that Arabidopsis 35S::LLA23 stomata remain opened upon drought, while transgenic plants have a decreased rate of water loss and exhibit enhanced drought and salt resistance. A dual function of the lily abscisic acid-, stress-, and ripening-induced protein molecule is discussed. [ABSTRACT FROM AUTHOR]

Confocal laser scanning microscopy (CLSM) and whole-cell patch-clamp were used to investigate the role of Ca2+ influx in maintaining the cytosolic Ca2+ concentration ([Ca2+]c) and the features of the Ca2+ influx pathway in germinating pollen grains of Lilium davidii D. [Ca2+]c decreased when Ca2+ influx was inhibited by EGTA or Ca2+ channel blockers. A hyperpolarization-activated Ca2+-permeable channel, which can be suppressed by trivalent cations, verapamil, nifedipine or diltiazem, was identified on the plasma membrane of pollen protoplasts with whole-cell patch-clamp recording. Calmodulin (CaM) antiserum and W7-agarose, both of which are cell-impermeable CaM antagonists, lead to a [Ca2+]c decrease, while exogenous purified CaM triggers a transient increase of [Ca2+]c and also remarkably activated the hyperpolarization-activated Ca2+ conductance on plasma membrane of pollen protoplasts in a dose-dependent manner. Both the increase of [Ca2+]c and the activation of Ca2+ conductance which were induced by exogenous CaM were inhibited by EGTA or Ca2+ channel blockers. This primary evidence showed the presence of a voltage-dependent Ca2+-permeable channel, whose activity may be regulated by extracellular CaM, in pollen cells. [ABSTRACT FROM AUTHOR]

Endo-β-mannosidase, which hydrolyzes the Manβ1-4GlcNAc linkage in the trimannosyl core structure of N-glycans, was recently purified to homogeneity from lily (Lilium longiflorum) flowers as a heterotrimer [Ishimizu, T., Sasaki, A., Okutani, S., Maeda, M., Yamagishi, M., and Hase, S. (2004) J. Biol. Chem. 279, 38555–38562]. Here, we describe the substrate specificity of the enzyme and cloning of its cDNA. The purified enzyme hydrolyzed pyridylaminated (PA-) MannManα1-6Manβ1-4GlcNAcβ1-4GlcNAc (n = 0–2) to MannManα1-6Man and GlcNAcβ1-4GlcNAc-PA. It did not hydrolyze PA-sugar chains containing Manα1-3Manβ and/or Xylβ1-2Manβ. The best substrate among the PA-sugar chains tested was Manα1-6Manβ1-4GlcNAcβ1-4GlcNAc-PA with a Km value of 1.2 mM. However, the enzyme displayed a marked preference for the corresponding glycopeptide, Manα1-6Manβ1-4GlcNAcβ1-4GlcNAc-peptide (Km value 75 µM). These results indicate that the substrate recognition by the enzyme involves the peptide portion attached to the N-glycan. Sequence information on the purified enzyme was used to clone the corresponding cDNA. The monocotyledonous lily enzyme (952 amino acids) displays 68% identity to its dicotyledonous (Arabidopsis thaliana) homologue. Our results show that the heterotrimeric enzyme is encoded by a single gene that gives rise to three polypeptides following posttranslational proteolysis. The enzyme is ubiquitously expressed, suggesting that it has a general function such as processing or degrading N-glycans. [ABSTRACT FROM PUBLISHER]

Pollinators such as bees are attracted to flowers by their visual display and their scent. Although most flowers reinforce visits by providing pollen and/or nectar, there are species—notably from the orchid family—that do not but do resemble rewarding species. These mimicry relationships provide ideal opportunities for investigating the evolution of floral signals and their impact on pollinator behavior. Here, we have reanalyzed a case of specialized food mimicry between the orchid Orchis israelitica and its model, the lily Bellevalia flexuosa. Based on current knowledge of insect sensory physiology, we were able to characterize both the visual and olfactory signals of model and mimic, as well as of two phylogenetically related orchids. By using a color vision model, we mapped each species' visual signals to the perceptual space of honeybees and found an apparent shift of the mimic's visual signals towards the model. We confirm that visual mimicry is present. We analyzed the flower odors by using gas chromatography/mass spectroscopy. We related these signals to the perceptual space of the pollinators by testing the scent extracts physiologically, using in vivo brain imaging. We found no evidence of olfactory mimicry. The results indicate that evolutionary pressure acts on the visual, but not olfactory, traits of O. israelitica toward a higher similarity to its model. Apparently, odor mismatch does not prevent a bee from landing on a flower that has the expected visual display. The results therefore argue for the dominance of visual stimuli in short-distance flower choice. The orchid may still depend on long-distance olfactory attraction originating from neighboring model plants. [ABSTRACT FROM AUTHOR]

While callose is a well-known permeability barrier and leak sealant in plant cells, it is largely unknown whether this cell wall polymer can also serve as a load-bearing structure. Since callose occurs in exceptionally large amounts in pollen, we assessed its role for resisting tension and compression stress in this cell. The effect of callose digestion in Solanum chacoense and Lilium orientalis pollen grains demonstrated that, depending on the species, this cell wall polymer represents a major stress-bearing structure at the aperture area of germinating grains. In the pollen tube, it is involved in cell wall resistance to circumferential tension stress, and despite its absence at the growing apex, callose is indirectly involved in the establishment of tension stress resistance in this area. To investigate whether or not callose is able to provide mechanical resistance against compression stress, we subjected pollen tubes to local deformation by microindentation. The data revealed that lowering the amount of callose resulted in reduced cellular stiffness and increased viscoelasticity, thus indicating clearly that callose is able to resist compression stress. Whether this function is relevant for pollen tube mechanics, however, is unclear, as stiffened growth medium caused a decrease in callose deposition. Together, our data provide clear evidence for the capacity of cell wall callose to resist tension and compression stress, thus demonstrating that this amorphous cell wall substance can have a mechanical role in growing plant cells. [ABSTRACT FROM AUTHOR]

It is well known that a tip-focused intracellular Ca2+ gradient and the meshwork of short actin filaments at the tip region are necessary for pollen tube growth. However, little is known about the connections between the two factors. Here, a novel Ca2+ dependent actin-binding protein with molecular mass of 41 kD from lily (Lilium davidii) pollen (LdABP41) was isolated and purified with DNase 1 chromatography. Our purification procedure yielded about 0.6 mg of LdABP41 with >98% purity from 10 g of lily pollen. At least two isoforms with isoelectric points of 5.8 and 6.0 were detected on two-dimensional gels. The results of N-terminal sequencing and mass-spectrometry analysis of LdABP41 showed that both isoforms shared substantial similarity with trumpet lily (Lilium longiflorum) villin and other members of the gelsolin superfamily. Negative-stained electron microscope images showed that LdABP41 severed in vitro-polymerized lily pollen F-actin into short actin filaments in a Ca2+-sensitive manner. Microinjection of the anti-LdABP41 antibody into germinated lily pollen demonstrated that the protein was required for pollen tube growth. The results of immunolocalization of the protein showed that it existed in the cytoplasm of the pollen tube, especially focused in the tip region. Our results suggest that LdABP41 belongs to the gelsolin superfamily and may play an important role in controlling actin organization in the pollen tube tip by responding to the oscillatory, tip-focused Ca2+ gradient. [ABSTRACT FROM AUTHOR]

In lily (Lilium longiflorum cv. Avita) pollen cold-stored (–20°C) for 2 months, typical in vitro germination/growth was delayed by about 1 h compared with fresh pollen. We hypothesized that some proteins and mRNAs stored in mature pollen were degraded during storage periods and that re-synthesis of them was essential to resume normal germination and growth. Cold-stored and fresh pollen grains were used to investigate the regulatory mechanism of pollen germination and tube growth in terms of both total protein profile and gene expression. Total protein profiles of cold-stored pollen differed qualitatively and quantitatively from fresh pollen. Actinomycin D significantly inhibited both germination and tube growth of cold-stored pollen and later tube growth of fresh pollen but had no effect on fresh pollen germination and early tube growth. Suppression subtractive hybridization screening revealed 99 cDNAs enriched in fresh mature pollen, and 22 were selected for further characterization. Most of these 22 cDNAs gradually disappeared during cold storage, but full recovery was achieved by incubating the cold-stored pollen in culture medium for 2 h. Because of different sensitivities to cold storage and actinomycin D, the transcripts were divided into three groups according to their possible roles in pollen germination and tube growth. Several cDNAs encoding novel proteins showed pollen-specific expression patterns and may participate in drought tolerance (an Na+/H+ antiporter), endomembrane trafficking (DnaJ), division of the generative cell (Sgt1), pollen wall precursor uptake from stylar exudate (an Na+/myoinositol symporter) and chemotropism of the pollen tube (peptide transporter) during pollination. [ABSTRACT FROM AUTHOR]

The ABC model for floral development was proposed more than 10 years ago and since then many studies have been performed on model species, such as Arabidopsis thaliana, Antirrhinum majus, and many other species in order to confirm this hypothesis. This led to additional information on flower development and to more complex molecular models. AGAMOUS (AG) is the only C type gene in Arabidopsis and it is responsible for stamen and carpel development as well as floral determinacy. LLAG1, an AG homologue from lily (Lilium longiflorum Thunb.) was isolated by screening a cDNA library derived from developing floral buds. The deduced amino acid sequence revealed the MIKC structure and a high homology in the MADS‐box among AG and other orthologues. Phylogenetic analysis indicated a close relationship between LLAG1 and AG orthologues from monocot species. Spatial expression data showed LLAG1 transcripts exclusively in stamens and carpels, constituting the C domain of the ABC model. Functional analysis was carried out in Arabidopsis by overexpression of LLAG1 driven by the CaMV35S promoter. Transformed plants showed homeotic changes in the two outer floral whorls with some plants presenting the second whorl completely converted into stamens. Altogether, these data strongly indicated the functional homology between LLAG1 and AG. [ABSTRACT FROM PUBLISHER]

Two AGL2-1ike MADS-box genes, Lily MADS Box Gene (LMADS) 3 and LMADS4, with extensive homology of LMADS3 to the Arabidopsis SEPALLATA3 were characterized from the lily (Lilium longiflorum). Both LMADS3 and LMADS4 mRNA were detected in the inflorescence meristem, in floral buds of different developmental stages, and in all four whorls of the flower organ. LMADS4 mRNA is also expressed in vegetative leaf and in the inflorescence stem where LMADS3 expression is absent. Transgenic Arabidopsis, which ectopically expresses LMADS3, showed novel phenotypes by significantly reducing plant size, flowering extremely early, and loss of floral determinacy. By contrast, 35S::LMADS4 transgenic plants were morphologically indistinguishable from wild-type plants. The early-flowering phenotype in 35S::LMADS3 transgenic Arabidopsis plants was correlated with the up-regulation of flowering time genes FT, SUPPRESSOR OF OVEREXPRESSION OF CO 1, LUMINIDEPENDENS, and flower meristem identity genes LEAFY and APETALA1. This result was further supported by the ability of 35S::LMADS3 to rescue the late-flowering phenotype in gigantea-1 (gi-1), constans-3 (co-3), and luminidependens-1 but not for ft-1 or fwa-1 mutants. The activation of these flowering time genes is, however, indirect because their expression was unaffected in plants transformed with LMADS3 fused with rat glucocorticoid receptor in the presence of both dexamethasone and cycloheximide. [ABSTRACT FROM AUTHOR]

Calcium ions (Ca2+), protons (H+), and borate (B(OH)4–) are essential ions in the control of tip growth of pollen tubes. All three ions may interact with pectins, a major component of the expanding pollen tube cell wall. Ca2+ is thought to bind acidic residues, and cross‐link adjacent pectin chains, thereby strengthening the cell wall. Protons are loosening agents; in pollen tube walls they may act through the enzyme pectin methylesterase (PME), and either reduce demethylation or stimulate hydrolysis of pectin. Finally, borate cross‐links monomers of rhamnogalacturonan II (RG‐II), and thus stiffens the cell wall. It is demonstrated here that changing the extracellular concentrations of Ca2+, H+ and borate affect not only the average growth rate of lily pollen tubes, but also influence the period of growth rate oscillations. The most dramatic effects are observed with increasing concentrations of Ca2+ and borate, both of which markedly reduce the rate of growth of oscillating pollen tubes. Protons are less active, except at pH 7.0 where growth is inhibited. It is noteworthy, especially with borate, that the faster growing tubes exhibit the shorter periods of oscillation. The results are consistent with the idea that binding of Ca2+ and borate to the cell wall may act at a similar level to alter the mechanical properties of the apical cell wall, with optimal concentrations being high enough to impart sufficient rigidity to the wall so as to prevent bursting in the face of cell turgor, but low enough to allow the wall to stretch quickly during periods of accelerating growth. [ABSTRACT FROM PUBLISHER]

An enzyme catalyzing the hydrolysis of the Manβ1-4GlcNAc linkage of N-linked sugar chains was partially purified and characterized. Endo-β-mannosidase activity was detected using pyridylaminated (PA-) Manα1–6Manβ1-4GlcNAcβ1-4GlcNAc as the substrate in a homogenate of lily flowers (Lilium longflorum Thumb). The enzyme was partially purified by ammonium sulfate precipitation, and Q-Sepharose, Superdex 200, hydroxyapatite, Poros PE/M, Mono Q, and Superdex 200 column chromatographies. The optimum pH was 5.0 and the estimated molecular weight of the enzyme was 78,000, as determined by gel filtration. The Km value found for Manα1-6Manβ1-4GlcNAcβ1-4GlcNAc-PA was 1.4 mM. The enzymatic activity was not influenced by the addition of 10 mM EDTA or 2mM Ca2+. Experiments on the hydrolysis of several PA-N-linked sugar chains revealed that the enzyme hydrolyzed ManαManα1-6Manβ1-4GlcNAcβ1-4GlcNAc-PA (n = 0–2) into a mixture of ManαManα1-6Man and GlcNAcβ1-4GlcNAc-PA, indicating that it is an endoglycosidase in nature. However, the enzyme did not hydrolyze β1–4mannohexaose or p-nitrophenyl β-mannopyranoside. [ABSTRACT FROM PUBLISHER]

Focuses on flora aroma, which serves to attract insect pollinators and assure cross-pollination and thus gene mixing and vigorous offspring. Heat and odor production by arum lilies; Soybean flowers and their potential chemical messages; Idea that orchid aromas may serve as either rewards or deceptions; Conclusion that floral aromas act as species identifiers, enabling pollinators to forage efficiently and helping plant species to maintain reproductive isolation from one another.

A letter to the editor is presented related to the correlation of actin fringe with tip growth velocity of pollen tubes in lily flower in the September 2012 issue.

Lily is a well-known ornamental plant with a diversity of fragrant types. Basic information on lily floral scent compounds has been obtained for only a few accessions, and little is known about Lilium aroma types, the terpene synthase genes that may play roles in the production of key volatiles, or the range of monoterpenes that these genes produce. In this study, 41 cultivars were analyzed for volatile emissions, and a total of 46 individual volatile compounds were identified, 16 for the first time in lilies. Lily accessions were classified into six groups according to the composition of major scent components: faint-scented, cool, fruity, musky, fruity-honey, and lily. Monoterpenes were one of the main groups of volatiles identified, and attention was focused on terpene synthase (TPS) genes, which encode enzymes that catalyze the last steps in monoterpene synthesis. Thirty-two candidate monoterpene synthase cDNAs were obtained from 66 lily cultivars, and 64 SNPs were identified. Two InDels were also shown to result from variable splicing, and sequence analysis suggested that different transcripts arose from the same gene. All identified nucleotide substitution sites were highly correlated with the amounts of myrcene emitted, and InDel site 230 was highly correlated with the emission of all major monoterpenoid components, especially (E)-β-ocimene. Heterologous expression of five cDNAs cloned from faint-scented and strong-scented lilies showed that their corresponding enzymes could convert geranyl diphosphate to (E)-β-ocimene, α-pinene, and limonene. The findings from this study provide a major resource for the assessment of lily scent volatiles and will be helpful in breeding of improved volatile components. [ABSTRACT FROM AUTHOR]

An introduction of several articles within the issue is presented on topics including modeling of crop yield of rice by genetic markers under drought stress, gender diphasy in lily and expression of gene during seed fill in sorghum.

In view of the recent isolation of stable oil bodies as well as a unique oleosin from lily pollen, this study examined whether other minor proteins were present in this lipid-storage organelle. Immunological cross-recognition using antibodies against three minor oil-body proteins from sesame suggested that a putative caleosin was specifically detected in the oil-body fraction of pollen extract. A cDNA fragment encoding this putative pollen caleosin, obtained by PCR cloning, was confirmed by immunodetection and MALDI-MS analyses of the recombinant protein over-expressed in Escherichia coli and the native form. Caleosin in lily pollen oil bodies seemed to be a unique isoform distinct from that in lily seed oil bodies. [ABSTRACT FROM AUTHOR]

Stable oil bodies were purified from mature lily (Lilium longiflorum Thunb.) pollen. The integrity of pollen oil bodies was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Immunodetection revealed that a major protein of 18 kDa was exclusively present in pollen oil bodies and massively accumulated in late stages of pollen maturation. According to mass spectrometric analyses, this oil body protein possessed a tryptic fragment of 13 residues matching that of a theoretical rice oleosin. A complete cDNA fragment encoding this putative oleosin was obtained by PCR cloning with primers derived from its known 13-residue sequence. Sequence analysis as well as immunological non-cross-reactivity suggests that this pollen oleosin represents a distinct class in comparison with oleosins found in seed oil bodies and tapetum. In pollen cells observed by electron microscopy, oil bodies were presumably surrounded by tubular membrane structures, and encapsulated in the vacuoles after germination. It seems that pollen oil bodies are mobilized via a different route from that of glyoxysomal mobilization of seed oil bodies after germination. [ABSTRACT FROM AUTHOR]