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El género Pisonia es primordialmente americano, se distribuye principalmente en regiones subtropicales y tropicales. En este trabajo se describe y documenta la nueva especie Pisonia calafia. Este taxon consiste de una relativamente pequeña población en la costa de la región de Los Cabos en la península de Baja California. La principal característica que diferencia a P. calafia del resto de las especies de este género es la carencia de sulcos y glándulas en el fruto. En adición a la descripción morfológica, se documenta la afinidad evolutiva del nuevo taxon con base en el análisis filogenético de la secuencia de nrITS. Las poblaciones conocidas consisten de unas pocas docenas de individuos, seriamente amenazados por el desarrollo de proyectos turísticos en la zona.

—Oenotherasect.Pachylophushas proven to be a valuable system in which to study plant-insect coevolution and the drivers of variation in floral morphology and scent. Current species circumscriptions based on morphological characteristics suggest that the section consists of five species, one of which is subdivided into five subspecies. Previous attempts to understand species (and subspecies) relationships at a molecular level have been largely unsuccessful due to high levels of incomplete lineage sorting and limited phylogenetic signal from slowly evolving gene regions. In the present study, target enrichment was used to sequence 322 conserved protein-coding nuclear genes from 50 individuals spanning the geographic range ofOenotherasect.Pachylophus, with species trees inferred using concatenation and coalescent-based methods. Our findings concur with previous research in suggesting thatO. psammophilaandO. harringtoniiare nested within a paraphyleticOenothera cespitosa. By contrast, our results show clearly that the two annual species (O. cavernaeandO. brandegeei) did not arise from theO. cespitosalineage, but rather from a common ancestor ofOenotherasect.Pachylophus. Budding speciation as a result of edaphic specialization appears to best explain the evolution of the narrow endemic speciesO. harringtoniiandO. psammophila. Complete understanding of possible introgression among subspecies ofO. cespitosawill require broader sampling across the full geographical and ecological ranges of these taxa.

Objective Although theoretical conceptualizations of suicide hold that passive and active suicidal ideation are etiologically distinct, existing research observing this distinction is modest, with most prior studies focusing exclusively on active ideation. Understanding processes associated with passive ideation is clinically important insofar as passive ideation may precede active ideation, and thus serve as an earlier intervention target prior to potential onset of suicidal behavior. We aimed to evaluate intrapersonal and interpersonal vulnerability and resilience factors for passive ideation and differentiating passive from active ideation. Method Left-behind adolescents in rural China (n = 371) were assessed for passive and active ideation, depressive symptoms, rumination, grit, peer support, and peer victimization. Results Overall, 15.9% of the sample endorsed passive ideation without active ideation, and 17.8% endorsed active ideation. In multivariate analyses, rumination and grit differentiated left-behind children with passive ideation from those with no ideation. Depressive symptom severity predicted active ideation among adolescents with passive ideation. Conclusions The current findings suggest that rumination and grit may characterize passive ideation. Although passive and active ideation may differ modestly in vulnerability and resilience factors, depressive symptoms may be important to monitor among those with passive ideation and have not yet experience active ideation.

The study of song development has focused on temperate zone birds in which typically only males sing. In the bay wren, Cantorchilus nigricapillu s, both sexes sing, performing precisely timed, female-initiated duets in which birds alternate sex-specific song phrases. We investigated the development of these sex differences by collecting bay wren eggs and nestlings, and hand-raising them in individual acoustic isolation chambers. Each bird was tutored with either monophonic or stereophonic recordings of bay wren duets or heard no song. As adults, each tutored bird sang repertoires of complete duets, singing both male and female phrases. In addition, some birds sang only the male or female part of some duets to which they were exposed. Mono-tutored birds showed no sex-specificity in these solo songs, whereas stereo-tutored birds only sang solos consistent with their sex. In addition, stereo-tutored birds acquired songs over a longer period than did mono-tutored birds, and stereo-tutored females showed more sex-specificity than did males during early song production. Finally, we observed that tutored and acoustically isolated birds of both sexes invented male-like songs, whereas only males invent songs in the wild. These results reveal the relative roles of environmental versus innate influences in the development of sex-specific song in this species.

Premise of research. Whole-genome duplication is often associated with the evolution of dimorphic sexual systems; however, the association is not universal, and the evolutionary pathway(s) underlyi...

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking noncoding regions, gene tree/species tree methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic, edaphic, and morphological diversity in the group. We found that the combination of exons and flanking noncoding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple evolutionary origins of bee pollination from ancestral hawkmoth pollination, edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively reconstruct the recalcitrant history of a rapid radiation. [Gypsum endemism; Oenothera sect. Calylophus; Onagraceae; phylogenomics; pollinator shift; recent radiation; target enrichment.]

Research suggests that various indicators of hypothalamic pituitary adrenal (HPA) axis activity prospectively predict depression, but few studies have evaluated whether trait indicators of HPA axis activity are related to depression. Further, no prior study has examined links between trait cortisol and psychopathology using a trait indicator that captures HPA axis activity over multiple time points. Here we examined whether we could construct an across-wave latent trait cortisol (LTC) factor using cortisol samples collected over 13 weeks, and whether the across-wave LTC prospectively predicted new depressive symptom onsets and symptom duration. Emerging adults (n = 85; M age = 19.37 years) provided salivary cortisol samples four times a day (waking, 30 min and 45 min post-waking and bedtime) over three 3-day measurement waves separated by 6 weeks. Diagnostic interviews at 3 timepoints (baseline, 1- and 2.5 years post-baseline) assessed lifetime and current depressive symptoms. Results indicated that the across-wave LTC predicted new onsets of depressive symptoms and longer symptom duration. Follow-up tests revealed that the link between the across-wave LTC and new onsets was not significant after adjusting for past depressive symptoms. These findings suggest that an indicator of individual differences in HPA axis regulation has implications for depressive symptom onsets and course.

Background: The relationship between life stress and depression and anxiety is well characterized in adolescents and adults. Further, research has shown that adolescents and adults with a history of childhood maltreatment are more likely to develop depression and anxiety after being exposed to stress than those without this history. However, the processes underlying risk for depression and anxiety in maltreated preadolescent children are unclear. The current study sought to identify these processes in at-risk preadolescents. Methods: This study analyzed data from the Longitudinal Studies of Child Abuse and Neglect and evaluated interpersonal and non-interpersonal life stress as predictors of depression and anxiety specifically, and internalizing symptoms more generally, in a sample of children vulnerable or exposed to maltreatment (n = 1,049). Participants were assessed repeatedly over a six-year period of early-to-mid childhood. Results: Interpersonal life stress prospectively predicted greater depression and anxiety, but not general internalizing symptoms after emotional and behavioral problems, as well as child's sex, family income and baseline maternal depressive symptoms, were covaried. Non-interpersonal life stress was not prospectively predictive of depression and anxiety or general internalizing symptoms. Limitations: The study was unable to identify specific types of interpersonal stress most relevant to risk for depression and anxiety in preadolescent children. Conclusions: These findings lend support for the importance of interpersonal stress when screening for risk for depression and anxiety among preadolescent children vulnerable or exposed to maltreatment. Early intervention to decrease the occurrence and impact of these stressors could have long-lasting impacts on this vulnerable population.

Secondary hyperparathyroidism (SHP) is a common complication of CKD that increases morbidity and mortality. In experimental SHP, increased parathyroid hormone (PTH) expression is due to enhancedAdenine-rich high-phosphate diets induced CKD in rats and mice. Parathyroid organ cultures and transfected cells were incubated with Pin1 inhibitors for their effect on PTH expression. Mass spectrometry was performed on both parathyroid andCKD led to changes in rat parathyroid proteome and phosphoproteome profiles, including KSRP phosphorylation at Pin1 target sites. Furthermore, both acute and chronic kidney failure led to parathyroid-specific Pin1 Ser16 and Ser71 phosphorylation, which disrupts Pin1 activity. Pharmacologic Pin1 inhibition, which mimics the decreased Pin1 activity in SHP, increased PTH expressionKidney failure leads to loss of parathyroid Pin1 activity by inducing Pin1 phosphorylation. This predisposes parathyroids to increase PTH production through impaired

Small increases in ocean temperature can disrupt the obligate symbiosis between corals and dinoflagellate microalgae, resulting in coral bleaching. Little is known about the genes that drive the physiological and bleaching response of algal symbionts to elevated temperature. Moreover, many studies to-date have compared highly divergent strains, making it challenging to accredit specific genes to contrasting traits. Here, we compare transcriptional responses at ambient (27°C) and bleaching-relevant (31°C) temperatures in a monoclonal, wild-type (WT) strain of Symbiodiniaceae to those of a selected-strain (SS), derived from the same monoclonal culture and experimentally evolved to elevated temperature over 80 generations (2.5 years). Thousands of genes were differentially expressed at a log fold-change of >8 between the WT and SS over a 35 days temperature treatment period. At 31°C, WT cells exhibited a temporally unstable transcriptomic response upregulating genes involved in the universal stress response such as molecular chaperoning, protein repair, protein degradation and DNA repair. Comparatively, SS cells exhibited a temporally stable transcriptomic response and downregulated many stress response genes that were upregulated by the WT. Among the most highly upregulated genes in the SS at 31°C were algal transcription factors and a gene probably of bacterial origin that encodes a type II secretion system protein, suggesting interactions with bacteria may contribute to the increased thermal tolerance of the SS. Genes and functional pathways conferring thermal tolerance in the SS could be targeted in future genetic engineering experiments designed to develop thermally resilient algal symbionts for use in coral restoration and conservation.

Parathyroid hormone (PTH) regulates serum calcium levels and bone strength. Secondary hyperparathyroidism (SHP) is a common complication of chronic kidney disease (CKD) that correlates with morbidity and mortality. In experimental SHP, the increased PTH gene expression is due to increased PTH mRNA stability and is mediated by protein-PTH mRNA interactions. Adenosine-uridine-rich binding factor 1 (AUF1) stabilizes and K-homology splicing regulatory protein (KSRP) destabilizes PTH mRNA. The peptidyl-prolyl cis/trans isomerase Pin1 acts on target proteins, including mRNA-binding proteins. Pin1 leads to KSRP dephosphorylation, but in SHP, parathyroid Pin1 activity is decreased and phosphorylated KSRP fails to bind PTH mRNA, leading to increased PTH mRNA stability and levels. A further level of post-transcriptional regulation occurs through microRNA (miRNA). Dicer mediates the final step of miRNA maturation. Parathyroid-specific Dicer knockout mice that lack miRNAs in the parathyroid develop normally. Surprisingly, these mice fail to increase serum PTH in response to both hypocalcemia and CKD, indicating that parathyroid Dicer and miRNAs are essential for stimulation of the parathyroid. Human and rodent parathyroids share similar miRNA profiles that are altered in hyperparathyroidism. The evolutionary conservation of abundant miRNAs and their regulation in hyperparathyroidism indicate their significance in parathyroid physiology and pathophysiology. let-7 and miR-148 antagonism modifies PTH secretion in vivo and in vitro, suggesting roles for specific miRNAs in parathyroid function. This review summarizes the current knowledge on the post-transcriptional mechanisms of PTH gene expression in SHP and the central contribution of miRNAs to the high serum PTH levels of both primary hyperparathyroidism and SHP.

Parathyroid hormone (PTH) regulates calcium metabolism and bone strength. Chronic kidney disease leads to secondary hyperparathyroidism (SHP) which increases morbidity and mortality. In experimental SHP, the increased PTH gene expression is due to enhanced PTH mRNA stability, mediated by changes in its interaction with stabilizing AUF1 and destabilizing KSRP. Pin1 isomerizes target proteins and leads to KSRP dephosphorylation. In SHP, Pin1 isomerase activity is decreased and phosphorylated KSRP fails to bind PTH mRNA, resulting in high PTH mRNA stability and levels. However, the up- and down-stream mechanisms by which kidney failure stimulates the parathyroid remain elusive. We now reveal a pathway where kidney failure induces parathyroid Pin1 phosphorylation, linking Pin1, KSRP and PTH mRNA stability as key players for the high PTH expression in SHP. We identified by mass-spectrometry, changes in rat parathyroid proteome and phosphoproteome profiles induced by impaired renal function, including KSRP phosphorylation at Pin1 target sites. Furthermore, both acute and chronic kidney failure led to parathyroid-specific Pin1 Ser16 and Ser71 phosphorylation, which disrupts Pin1 activity. Accordingly, pharmacologic Pin1 inhibition, that mimics the decreased Pin1 activity in SHP, increased PTH expression ex-vivo in parathyroid organ cultures and in transfected cells, through the PTH mRNA protein-interacting element and KSRP phosphorylation at potential Pin1-binding motifs. Therefore, kidney failure leads to loss of parathyroid Pin1 activity by inducing Pin1 phosphorylation. This predisposes parathyroids to increase PTH production through impaired PTH mRNA decay that is dependent on KSRP phosphorylation. Pin1 and KSRP phosphorylation and the Pin1-KSRP-PTH mRNA axis thus drive SHP.

The present study evaluated sociodemographic and diagnostic predictors of suicidal ideation and attempts in a nationally representative sample of preadolescent youth enrolled in the Adolescent Brain Cognitive Development Study. Rates and predictors of psychiatric treatment utilization among suicidal youth also were examined. Eleven thousand eight hundred and seventy-five 9- and 10-year-old children residing in the United States were assessed. Children and their parents/guardians provided reports of children’s lifetime history of suicidal ideation, suicide attempts, and psychiatric disorders. Parents also reported on sociodemographic characteristics and mental health service utilization. Multivariate logistic regression analyses were employed to evaluate sociodemographic and diagnostic correlates of suicidal ideation, suicide attempts among youth with suicidal ideation, and treatment utilization among youth with suicidal ideation and suicide attempts. Lifetime prevalence rates were 14.33% for suicidal ideation and 1.26% for suicide attempts. Youth who identified as male, a sexual minority, or multiracial had greater odds of suicidal ideation, and sexual minority youth and youth with a low family income had greater odds of suicide attempts. Comorbid psychopathology was associated with higher odds of both suicidal ideation and suicide attempts. In youth, 34.59% who have suicidal ideation and 54.82% who had attempted suicide received psychiatric treatment. Treatment utilization among suicidal youth was lower among those who identified as female, Black, and Hispanic. Suicidal ideation and attempts among preadolescent children are concerningly high and targeted assessment and preventative efforts are needed, especially for males, racial, ethnic, and sexual minority youth, and those youth experiencing comorbidity.

Premise As Baker's law suggests, the successful colonization of oceanic islands is often associated with uniparental reproduction (self-fertility), but the high incidence of dimorphism (dioecy, gynodioecy) on islands complicates this idea. Lycium carolinianum is widespread, occurring on the North American mainland and the Hawaiian Islands. We examined Baker's ideas for mainland and island populations of L. carolinianum and examined inbreeding depression as a possible contributor to the evolution of gynodioecy on Maui. Methods Controlled crosses were conducted in two mainland populations and two populations in Hawaii. Treatments included self and cross pollination, unmanipulated controls, and autogamy/agamospermy. Alleles from the self-incompatibility S-RNase gene were isolated and compared between mainland and island populations. Given self-compatibility in Hawaii, we germinated seeds from self- and cross- treatments and estimated inbreeding depression using seven traits and a measure of cumulative fitness. Results Mainland populations of Lycium carolinianum are predominately self-incompatible with some polymorphism for self-fertility, whereas Hawaiian populations are self-compatible. Concordantly, S-RNase allelic diversity is reduced in Hawaii compared to the mainland. Hawaiian populations also exhibit significant inbreeding depression. Conclusions Self-compatibility in Hawaii and individual variation in self-fertility in mainland populations suggests that a colonization filter promoting uniparental reproduction may be acting in this system. Comparison of S-RNase variation suggests a collapse of allelic diversity and heterozygosity at the S-RNase locus in Hawaii, which likely contributed to mate limitation upon arrival to the Pacific. Inbreeding depression coupled with autonomous self-fertilization may have led to the evolution of gynodioecy on Maui.

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking non-coding regions, summary coalescent methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic and morphological diversity in the group. We found that the combination of exons and flanking non-coding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple origins of the evolution of bee pollination from ancestral hawkmoth pollination, the evolution of edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively address a relatively common but recalcitrant problem in evolutionary biology.

BackgroundPlant volatiles play an important role in both plant-pollinator and plant-herbivore interactions. Intraspecific polymorphisms in volatile production are ubiquitous, but studies that explore underlying differential gene expression are rare. Oenothera harringtonii populations are polymorphic in floral emission of the monoterpene (R)-(-)-linalool; some plants emit (R)-(-)-linalool (linalool+ plants) while others do not (linalool-plants). However, the genes associated with differential production of this floral volatile in Oenothera are unknown. We used RNA-Seq to broadly characterize differential gene expression involved in (R)-(-)-linalool biosynthesis. To identify genes that may be associated with the polymorphism for this trait, we used RNA-Seq to compare gene expression in six different Oenothera harringtonii tissues from each of three linalool+ and linalool-plants.ResultsThree clusters of differentially expressed genes were enriched for terpene synthase activity: two were characterized by tissue-specific upregulation and one by upregulation only in plants with flowers that produce (R)-(-)-linalool. A molecular phylogeny of all terpene synthases identified two putative (R)-(-)-linalool synthase transcripts in Oenothera harringtonii, a single allele of which is found exclusively in linalool+ plants.ConclusionsBy using a naturally occurring polymorphism and comparing different tissues, we were able to identify genes putatively involved in the biosynthesis of (R)-(-)-linalool. Expression of these genes in linalool-plants suggests a regulatory polymorphism, rather than a population-specific loss-of-function allele. Additional terpene biosynthesis-related genes that are up-regulated in plants that emit (R)-(-)-linalool may be associated with herbivore defense, suggesting a potential economy of scale between plant reproduction and defense.

Secondary hyperparathyroidism (SHP) is a common complication of chronic kidney disease (CKD) that induces morbidity and mortality in patients. How CKD stimulates the parathyroid to increase parathyroid hormone (PTH) secretion, gene expression and cell proliferation remains an open question. In experimental SHP, the increased PTH gene expression is post-transcriptional and mediated by PTH mRNA–protein interactions that promote PTH mRNA stability. These interactions are orchestrated by the isomerase Pin1. Pin1 participates in conformational change-based regulation of target proteins, including mRNA-binding proteins. In SHP, Pin1 isomerase activity is decreased, and thus, the Pin1 target and PTH mRNA destabilizing protein KSRP fails to bind PTH mRNA, increasing PTH mRNA stability and levels. An additional level of post-transcriptional regulation is mediated by microRNA (miRNA). Mice with parathyroid-specific knockout of Dicer, which facilitates the final step in miRNA maturation, lack parathyroid miRNAs but have normal PTH and calcium levels. Surprisingly, these mice fail to increase serum PTH in response to hypocalcemia or uremia, indicating a role for miRNAs in parathyroid stimulation. SHP often leads to parathyroid hyperplasia. Reduced expressions of parathyroid regulating receptors, activation of transforming growth factor α-epidermal growth factor receptor, cyclooxygenase 2-prostaglandin E2 and mTOR signaling all contribute to the enhanced parathyroid cell proliferation. Inhibition of mTOR by rapamycin prevents and corrects the increased parathyroid cell proliferation of SHP. This review summarizes the current knowledge on the mechanisms that stimulate the parathyroid cell at multiple levels in SHP.

Premise Long-distance dispersal has been important in explaining the present distributions of many plant species. Despite being infrequent, such dispersal events have considerable evolutionary consequences, because bottlenecks during colonization can result in reduced genetic diversity. We examined the phylogeographic history of Lycium carolinianum, a widespread taxon that ranges from southeastern North America to several Pacific islands, with intraspecific diversity in sexual and mating systems. Methods We used Bayesian, likelihood, and coalescent approaches with nuclear and plastid sequence data and genome-wide single nucleotide polymorphisms to reconstruct the dispersal history of this species. We also compared patterns of genetic variation in mainland and island populations using single nucleotide polymorphisms and allelic diversity at the S-RNase mating system gene. Results Lycium carolinianum is monophyletic and dispersed once from the North American mainland, colonizing the Pacific islands ca. 40,100 years ago. This dispersal was accompanied by a loss of genetic diversity in SNPs and the S-RNase locus due to a colonization bottleneck and the loss of self-incompatibility. Additionally, we documented at least two independent transitions to gynodioecy: once following the colonization of the Hawaiian Islands and loss of self-incompatibility, and a second time associated with polyploidy in the Yucatan region of Mexico. Conclusions Long-distance dispersal via fleshy, bird dispersed fruits best explains the unusually widespread distribution of L. carolinianum. The collapse of diversity at the S-RNase locus in island populations suggests that self-fertilization may have facilitated the subsequent colonization of Pacific islands following a single dispersal from mainland North America.

Lycium is the only member of tribe Lycieae (Solanoideae, Solanaceae), and it has a cosmopolitan distribution with its greatest diversity in southern South America, southern Africa, and southwestern North America. To date, there has been no attempt to synthesize and evaluate the significance of the available cytogenetical data from a phylogenetic perspective, which is the objective of this study. Firstly, new data on 27 taxa from all its range of distribution (FISH in all of them, banding in 23, Feulgen technique in 14) were provided to fill gaps in the information. The chromosome numbers of L. australe, L. humile, and L. repens were recorded for the first time. Species showed x = 12 with different ploidy levels (mostly diploid or tetraploid), small chromosomes, and symmetrical karyotypes. Lycium fremontii and L. repens were outstanding for having the highest numbers reported for the genus: 10x and 11x, respectively. North American species showed comparatively longer chromosomes. Secondly, cytogenetical traits were mapped on a phylogenetic tree, using character mapping and ancestral states reconstruction, to understand the dynamics of the evolutionary changes. The main cytotaxonomical features were included: chromosome number, presence of polyploidy, total length of the haploid chromosome set, mean chromosome length, karyotype formula, A1 and A2 asymmetry indices, percentage of heterochromatin, number of CMA+ /DAPI− NORs bands, and number and position of 5S and 18S-5.8S-26S sites. The mean chromosome length, total haploid chromosome length, number of 18S-5.8S-26S loci, number of CMA+/DAPI− NORs bands underwent comparatively few transitions compared with the ploidy level and number of 5S loci. The mapping of the characters on the phylogenetic tree showed that the most probable ancestral chromosome number was 2n = 24 with several independent polyploidization events and one pair of eachrDNA locus. The most likely ancestral condition for the genus would be: diploid, with small chromosomes, scarce heterochromatin, asynteny of rDNA loci, and one pair of both 18S-5.8S-26S and 5S loci. Fil: Stiefkens, Laura Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Las Peñas, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Levin Rachel A.. Amherst College; Estados Unidos Fil: Miller Jill S.. Amherst College; Estados Unidos Fil: Bernardello, Gabriel Luis Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

// Rachel A. Levin 1 , Maria E. Lund 1 , Quach Truong 1 , Angela Wu 1 , Neal D. Shore 2 , Daniel R. Saltzstein 2 , Raoul S. Concepcion 2 , Thomas A. Paivanas 2 , Arletta van Breda 2 , Jennifer Beebe-Dimmer 3 , Julie J. Ruterbusch 3 , Sandra Wissmueller 1 , Douglas H. Campbell 1 and Bradley J. Walsh 1 1 Minomic International Ltd, Sydney, New South Wales, Australia 2 CUSP LLC Research Consortium, Annandale, VA, USA 3 Barbara Ann Karmanos Cancer Institute and Wayne State University, School of Medicine, Department of Oncology, Detroit, MI, USA Correspondence to: Bradley J. Walsh, email: brad.walsh@minomic.com Keywords: prostate cancer; biomarker; glypican-1; MIL-38; 3G5 Received: October 07, 2017 Accepted: March 11, 2018 Published: April 27, 2018 ABSTRACT Prostate cancer is responsible for hundreds of thousands of annual deaths worldwide. The current gold standard in early detection of prostate cancer, the prostate specific antigen test, boasts a high sensitivity but low specificity, resulting in many unnecessary prostate biopsies. Thus, emphasis has been placed on identifying new biomarkers to improve prostate cancer detection. Glypican-1 has recently been proposed as one such biomarker, however further exploration into its predictive power has been hindered by a lack of available, dependable glypican-1 immunoassays. Previously, we identified human glypican-1 as the antigenic target of the MIL-38 monoclonal antibody. Additionally, we have now generated another monoclonal antibody, 3G5, that also recognizes human glypican-1. Here we report the development of a reliable, custom Luminex ® assay that enables precise quantitation of circulating human glypican-1 in plasma and serum. Using this assay, we show for the first time that circulating glypican-1 levels can differentiate non-cancer (normal and benign prostatic hyperplasia) patients from prostate cancer patients, as well as benign prostatic hyperplasia patients alone from prostate cancer patients. Our findings strongly promote future investigation into the use of glypican-1 for early detection of prostate cancer.

Premise of the study Floral morphology is expected to evolve following the transition from cosexuality to gender dimorphism in plants, as selection through male and female function becomes dissociated. Specifically, male-biased dimorphism in flower size can arise through selection for larger flowers through male function, selection for smaller flowers through female function, or both. The evolutionary pathway to floral dimorphism can be most effectively reconstructed in species with intraspecific variation in sexual system. We examined the evolution of flower size and shape in Lycium californicum, whose populations are either gender dimorphic with male and female plants, or cosexual with hermaphroditic plants. Methods Floral morphology was characterized in populations spanning the species' complete range. For a subset of the range where cosexual and dimorphic populations are in close proximity, we compared the size and shape of flowers from female and male plants in dimorphic populations to hermaphrodites in cosexual populations, accounting for variation associated with abiotic environmental conditions. Key results The magnitude of flower size dimorphism varied across dimorphic populations. After controlling for environmental variation across cosexual and dimorphic populations, flowers on males were larger than flowers on females and hermaphrodites, whereas flower size did not differ between females and hermaphrodites. Flower shape differences were associated with mating type, sexual system, and environmental variation. Conclusions While abiotic environmental gradients shape both overall flower size and shape, male-biased flower size dimorphism in L. californicum appears to arise through selection for larger flowers in males but not smaller flowers in females.

Background Increasing numbers of patients are presenting with aggressive prostate cancer (CaP); therefore, there exists a need to optimally identify these patients pre-biopsy. Objectives To compare the accuracy of total prostate specific antigen (PSA), %free PSA, and prostate health index (PHI) to differentiate between patients without CaP, with non-aggressive (Gleason 3 + 3, non-AgCaP) and with aggressive (Gleason ≥ 3 + 4, AgCaP) in a contemporary US population. Design, settings, and participants Serum samples were collected from 332 US patients scheduled for biopsy due to an elevated age-adjusted PSA. Site and Central biopsy pathologic assessment were performed. Outcome measurements and statistical analysis Testing of PSA, free PSA, proPSA, and PHI was performed along with central pathology review. Test performance using logistic regression analysis for differentiating CaP from non-CaP as well as non-AgCaP from AgCaP was evaluated. Results and limitations Central pathology review resulted in 32 upgrades including 14 Gleason 3 + 3 scores being upgraded to AgCaP with final distribution of 148 no-CaP, 64 non-AgCaP, and 120 AgCaP patients. Receiver operator curve (ROC) analysis of the different tests showed that PHI performed best at differentiating CaP from no-CaP subjects (area under the receiver operator curve 0.79). In contrast, the different tests were essentially equivalent in differentiating AgCaP vs. non-AgCaP. Conclusions In this recent US study of prebiopsy patients we observed a high proportion of AgCaP patients consistent with previous studies in contemporary US populations. Central Gleason review is recommended for multi-institutional studies comparing biomarkers. PHI was superior to PSA, free PSA, %free PSA, and proPSA in detecting CaP in this population but was not superior at differentiating AgCaP from non-AgCaP.

Background A clinical need exists for a biomarker test to accurately delineate aggressive prostate cancer (AgCaP), and thus better assist clinicians and patients decision-making on whether to proceed to prostate biopsy. Objectives To develop a blood test for AgCaP and compare to PSA, %free PSA, proPSA, and prostate health index (PHI) tests. Design, settings and participants Patient samples from the MiCheck-01 trial were used for development of the MiCheck test. Methods Serum analyte concentrations for cellular growth factors were determined using a custom-made Luminex-based R&D Systems multianalyte kit. Outcome measurements and statistical analysis Bayesian model averaging and random forest approaches were used to identify clinical factors and growth factors able to distinguish between men with AgCaP (Gleason Score [GS] ≥3+4) from those with non-AgCaP (GS 3+3). Logistic regression and Monte Carlo cross-validation identified variable combinations in order to able to maximize differentiation of AgCaP from non-AgCaP. Results The MiCheck logistic regression model was developed and comprises the following variables: serum prostate-specific antigen (PSA), patient age, Digital Rectal Exam (DRE) status, Leptin, IL-7, vascular endothelial growth factor, and Glypican-1. The model differentiated AgCaP from non-AgCaP with an area under the curve of 0.83 and was superior to PSA, %free PSA and PHI in all patient groups, regardless of PSA range. Applying the MiCheck test to all evaluable biopsy patients from the MiCheck-01 study demonstrated that up to 30% of biopsies could be avoided while delaying diagnosis of only 6.8% of GS ≥3+4 cancers, 5% of GS ≥4+3 cancers and no cancers of GS 8 or higher. Conclusions The MiCheck test outperforms PSA, %free PSA and PHI tests in differentiating AgCaP vs. non-AgCaP patients. The MiCheck test could result in a significant number of biopsies being avoided with a low number of patients experiencing a delayed diagnosis.

Premise of research. Whereas most Lycium species are diploid and hermaphroditic, an association across Lycium species has been demonstrated between higher ploidy levels and gender dimorphism. Previous monographic work, in combination with a single tetraploid chromosome count, suggested that the Galapagos endemic Lycium minimum may be dimorphic. If substantiated, this would be the only documented Lycium species from South America to be dimorphic in gender expression, which is especially notable given that species diversity is highest in South America. The goals of this study are to (1) test the monophyly, characterize population-level genetic diversity, and determine the closest mainland relatives of L. minimum; (2) infer the sexual system of L. minimum; and (3) assess/verify ploidy using DNA content measurements.Methodology. Phylogenetic, morphological, and cytometric approaches were used to document evolutionary affinities, gynodioecy, and polyploidy. Phylogenetic analyses were conducted with DNA sequenc...

 Premise of the study: An association between polyploidy and gender dimorphism has been noted in several plant lineages. Whereas the majority of Lycium species are diploid and have hermaphroditic fl owers in cosexual populations, gender dimorphism (gynodioecy, dioecy) has been shown to be uniformly associated with polyploidy in previous studies. Preliminary fi eld observations suggested that some populations of Lycium carolinianum were dimorphic, providing a test of this association.  Methods: We assessed sexual systems and cytotype variation (to infer ploidy) across 17 populations of L. carolinianum . Comparison of fl owers in cosexual and dimorphic populations were used to infer changes in reproductive morphology associated with the evolution of gynodioecy.  Key results: The majority of populations were cosexual in gender expression, but dimorphism was present in the Yucat a�n and in some populations in Hawaii. Populations varied in ploidy and were either diploid or tetraploid. Floral sexual dimorphism was present in all gynodioecious populations, though the magnitude differed and was cryptic in some cases. Our results are consistent with the hypothesis that following the evolution of gynodioecy, fl owers on hermaphrodites increased in size.  Conclusions: Dimorphic sexual systems have likely evolved convergently in L. carolinianum . In contrast to previous studies, dimorphism is not perfectly associated with polyploidy. Although our sample from the Yucat a�n was both tetraploid and dimorphic, all populations in Hawaii were diploid regardless of sexual system. Ongoing phylogeographic and mating system studies will contribute to our understanding of reproductive evolution in this widespread, polymorphic species.

© 2017 International Society for Microbial Ecology All rights reserved 1751-7362/17. Symbiodinium, the dinoflagellate photosymbiont of corals, is posited to become more susceptible to viral infections when heat-stressed. To investigate this hypothesis, we mined transcriptome data of a thermosensitive and a thermotolerant type C1 Symbiodinium population at ambient (27 °C) and elevated (32°C) temperatures. We uncovered hundreds of transcripts from nucleocytoplasmic large double-stranded DNA viruses (NCLDVs) and the genome of a novel positive-sense single-stranded RNA virus (+ssRNAV). In the transcriptome of the thermosensitive population only, +ssRNAV transcripts had remarkable expression levels in the top 0.03% of all transcripts at 27 °C, but at 32 °C, expression levels of +ssRNAV transcripts decreased, while expression levels of anti-viral transcripts increased. In both transcriptomes, expression of NCLDV transcripts increased at 32 °C, but thermal induction of NCLDV transcripts involved in DNA manipulation was restricted to the thermosensitive population. Our findings reveal that viruses infecting Symbiodinium are affected by heat stress and may contribute to Symbiodinium thermal sensitivity.

Dinoflagellates within the genus Symbiodinium are photosymbionts of many tropical reef invertebrates, including corals, making them central to the health of coral reefs. Symbiodinium have therefore gained significant research attention, though studies have been constrained by technical limitations. In particular, the generation of viable cells with their cell walls removed (termed protoplasts) has enabled a wide range of experimental techniques for bacteria, fungi, plants, and algae such as ultrastructure studies, virus infection studies, patch clamping, genetic transformation, and protoplast fusion. However, previous studies have struggled to remove the cell walls from armored dinoflagellates, potentially due to the internal placement of their cell walls. Here, we produce the first Symbiodinium protoplasts from three genetically and physiologically distinct strains via incubation with cellulase and osmotic agents. Digestion of the cell walls was verified by a lack of Calcofluor White fluorescence signal and by cell swelling in hypotonic culture medium. Fused protoplasts were also observed, motivating future investigation into intra- and inter-specific somatic hybridization of Symbiodinium. Following digestion and transfer to regeneration medium, protoplasts remained photosynthetically active, regrew cell walls, regained motility, and entered exponential growth. Generation of Symbiodinium protoplasts opens exciting, new avenues for researching these crucial symbiotic dinoflagellates, including genetic modification.

© 2016 The Author. Corals rely on photosynthesis by their endosymbiotic dinoflagellates (Symbiodinium spp.) to form the basis of tropical coral reefs. High sea surface temperatures driven by climate change can trigger the loss of Symbiodinium from corals (coral bleaching), leading to declines in coral health. Different putative species (genetically distinct types) as well as conspecific populations of Symbiodinium can confer differing levels of thermal tolerance to their coral host, but the genes that govern dinoflagellate thermal tolerance are unknown. Here we show physiological and transcriptional responses to heat stress by a thermo-sensitive (physiologically susceptible at 32 °C) type C1 Symbiodinium population and a thermo-tolerant (physiologically healthy at 32 °C) type C1 Symbiodinium population. After nine days at 32 °C, neither population exhibited physiological stress, but both displayed up-regulation of meiosis genes by ≥ 4-fold and enrichment of meiosis functional gene groups, which promote adaptation. After 13 days at 32 °C, the thermo-sensitive population suffered a significant decrease in photosynthetic efficiency and increase in reactive oxygen species (ROS) leakage from its cells, whereas the thermo-tolerant population showed no signs of physiological stress. Correspondingly, only the thermo-tolerant population demonstrated up-regulation of a range of ROS scavenging and molecular chaperone genes by ≥ 4-fold and enrichment of ROS scavenging and protein-folding functional gene groups. The physiological and transcriptional responses of the Symbiodinium populations to heat stress directly correlate with the bleaching susceptibilities of corals that harbored these same Symbiodinium populations. Thus, our study provides novel, foundational insights into the molecular basis of dinoflagellate thermal tolerance and coral bleaching.

TPS152 Background: A diagnostic test which can better inform both clinicians and patients regarding a decision to proceed with a prostate biopsy, while still utilizing traditional parameters of Prostate Specific Antigen (PSA) kinetics and/or the digital rectal examination (DRE) is still an unmet need. The MiCheck® test is designed as a triage test to assist clinicians in the decision to proceed to prostate biopsy. The MiCheck®test is a simple blood test that measures the levels of the Glypican-1 protein and related signalling molecules. The MiCheck®-01 prospective trial builds on a previous pilot trial that examined the ability of the MiCheck® test to distinguish between normal subjects, patients with benign disease or Gleason 7 and above prostate cancer. The MiCheck® test showed sensitivity of 60% and specificity of 96% in distinguishing between subjects with Gleason ≥7 and normal or BPH patients. In a separate study, the MiCheck® test could differentiate aggressive (GS ≥3+4) from non-aggressive (GS 3+3) prostate cancer with a sensitivity of 85% and specificity of 90%. Methods: The trial consists of two arms: Arm 1 (normal patients, n = 50) and Arm 2 (prostate biopsy patients, n = 300). Inclusion criteria: Arm 1: Age ≥50, Low PSA (performed at most 12 months prior, defined as PSA < 1.5 ng/mL between ages 50 and 60 and PSA < 3 ng/mL above age 60). Arm2: Age ≥40, all subjects who are referred for or have undergone either a de novo or a repeat prostate biopsy for high PSA (defined as PSA ≥ 1 ng/ml between ages 40 and 49, PSA ≥2 ng/mL between ages 50 and 60 and PSA ≥ 3 ng/mL for age 60 and above age 60). Key exclusion criteria: prior history of cancer, patients taking ADT, DRE or other prostate manipulation within 72 hrs, subjects taking 5 ARIs. Results: The trial has recruited 30 Arm 2 patients to date. Interim analyses will be performed following accrual of 100 and 200 Arm 2 patients. Full accrual is expected by mid Q4 2017. Conclusions: Interim analysis data will be presented showing test performance. COI and Funding: The trial is funded by Minomic International Ltd. Neal Shore is a member of Minomic’s Clinical Advisory Panel.

Chromosomal analyses of several southern African Lycium species resulted in diploid (2n = 24: L. amoenum, L. bosciifolium, L. ferocissimum, L. oxycarpum, L. tenue), tetraploid (2n = 48: L. gariepense, L. strandveldense, L. hantamense), and hexaploid (2n = 72: L. tetrandrum) counts. Chromosomes in all species were short (mean length = 2.00 μm; mean haploid genome length = 23.77 μm). Further, all species shared a highly symmetrical karyotype formula with 10 m pairs and 2 sm pairs, except L. bosciifolium with only one sm pair. The first m pair had a terminal microsatellite on the short arms. Fluorescent chromosome banding patterns with CMA/ DAPI staining in the diploid species showed NOR-associated heterochromatin in the first satellited pair. The tetraploids L. gariepense and L. hantamense had two chromosome pairs with a CMA+/DAPI−terminal band. Phylogenetic studies have shown that the southern African species are included in a monophyletic group including all Old World Lycium; these species are like...

The identification of genomic regions with sufficient variation to elucidate fine-scale relationships among closely related species is a major goal of phylogenetic systematics. However, the accumulation of such multi-locus data sets brings its own challenges, given that gene trees do not necessarily represent the true species tree. Using genomic tools developed for Solanum (Solanaceae), we have evaluated the utility of nuclear conserved ortholog set II (COSII) regions for phylogenetic inference in tribe Lycieae (Solanaceae). Five COSII regions, with intronic contents ranging from 68% to 91%, were sequenced in 10 species. Their phylogenetic utility was assessed and compared with data from more commonly used nuclear (GBSSI, nrITS) and cpDNA spacer data. We compared the effectiveness of a traditional total evidence concatenation approach versus the recently developed Bayesian estimation of species trees (BEST) method to infer species trees given multiple independent gene trees. All of the sampled COSII regions had high numbers of parsimony-informative (PI) characters, and two of the COSII regions had more PI characters than the GBSSI, ITS, and cpDNA spacer data sets combined. COSII markers are a promising new tool for phylogenetic inference in Solanaceae, and should be explored in related groups. Both the concatenation and BEST approaches yielded similar topologies; however, when multiple individuals with polyphyletic alleles were included, BEST was clearly the more robust approach for inferring species trees in the presence of gene tree incongruence.

The identification of plastid DNA markers that provide sufficient phylogenetic resolution at the species and population levels is an important challenge for plant systematics. This is mainly due to the relatively slow rate of evolution of the plastid genome. In this study, we examine the utility of several plastid DNA regions for phylogenetic inference at low taxonomic levels in tribe Lycieae (Solanaceae). The regions employed here previously provided considerable numbers of potentially informative characters in investigations of sequence variation across the plastid genome, and one region (trnH-psbA) has been advocated for use in DNA barcoding. We sequenced nine noncoding plastid DNA regions (∼8,400 bp) for a diverse sample of Lycium species and Phrodus microphyllus (tribe Lycieae), as well as the outgroup Nolana, and included published sequences from the distant outgroup Atropa. The nine regions varied with regard to their phylogenetic utility, as measured by the numbers of variable and parsimo...

There has been considerable interest and research into the benefits of multiple low-copy nuclear regions for phylogenetic studies at low taxonomic levels. In this study, the phylogenetic utility of DNA sequence data from two low-copy nuclear genes, nitrate reductase (NIA) and granule-bound starch synthase I (GBSSI), was compared with data from nuclear ribosomal ITS and the cpDNA spacers trnT-trnF and trnD-trnT across 33 closely related taxa in tribe Lycieae (Solanaceae). The NIA data (introns 1-2) had the most parsimony-informative characters, with over twice the number provided by GBSSI, but NIA also had greater homoplasy. Although gene trees were generally concordant across the four regions, there were some notable areas of incongruence, suggesting both incomplete lineage sorting as well as possible reticulate origins.

Over 50 years ago, Baker (1955, 1967) suggested that self-compatible species were more likely than self-incompatible species to establish new populations on oceanic islands. His logic was straightforward and rested on the assumption that colonization was infrequent; thus, mate limitation favored the establishment of self-fertilizing individuals. In support of Baker's rule, many authors have documented high frequencies of self-compatibility on islands, and recent work has solidified the generality of Baker's ideas. The genus Lycium (Solanaceae) has ca. 80 species distributed worldwide, and phylogenetic studies suggest that Lycium originated in South America and dispersed to the Old World a single time. Previous analyses of the S-RNase gene, which controls the stylar component of self-incompatibility, have shown that gametophytically controlled self-incompatibility is ancestral within the genus, making Lycium a good model for investigating Baker's assertions concerning reproductive assurance following oceanic dispersal. Lycium is also useful for investigations of reproductive evolution, given that species vary both in sexual expression and the presence of self-incompatibility. A model for the evolution of gender dimorphism suggests that polyploidy breaks down self-incompatibility, leading to the evolution of gender dimorphism, which arises as an alternative outcrossing mechanism. There is a perfect association of dimorphic gender expression, polyploidy, and self-compatibility (vs. cosexuality, diploidy, and self-incompatibility) among North American Lycium. Although the association between ploidy level and gender expression also holds for African Lycium, to date no studies of mating systems have been initiated in Old World species. Here, using controlled pollinations, we document strong self-incompatibility in two cosexual, diploid species of African Lycium. Further, we sequence the S-RNase gene in 15 individuals from five cosexual, diploid species of African Lycium and recover 24 putative alleles. Genealogical analyses indicate reduced trans-generic diversity of S-RNases in the Old World compared to the New World. We suggest that genetic diversity at this locus was reduced as a result of a founder event, but, despite the bottleneck, self-incompatibility was maintained in the Old World. Maximum-likelihood analyses of codon substitution patterns indicate that positive Darwinian selection has been relatively strong in the Old World, suggesting the rediversification of S-RNases following a bottleneck. The present data thus provide a dramatic exception to Baker's rule, in addition to supporting a key assumption of the Miller and Venable (2000) model, namely that self-incompatibility is associated with diploidy and cosexuality.

We examine evolutionary relationships among the three genera in tribe Lycieae using DNA sequence data from the nuclear granule-bound starch synthase gene (GBSSI, waxy). Tribe Lycieae is comprised of the large cosmopolitan genus Lycium and the predominately South American genera Grabowskia and Phrodus. Phylogenetic results strongly suggest that Lycium contains Grabowskia and may also include Phrodus. Further, we examine relationships among several clades of American Lycium and within the monophyletic Old World lineage. This study has the largest taxon sampling to date for tribe Lycieae, with 85% of the named species. Increased sampling within eastern Asia and South America, with the world’s highest species-richness of Lycium, as well as the addition of more rapidly evolving genetic markers, are the areas on which to focus future work.

Species of Solanum subgenus Leptostemonum comprise almost one third of the genus and are distributed worldwide. Members of this group are defined by their sharp epidermal prickles; thus, they are commonly referred to as the ‘‘spiny solanums.’’ This subgenus includes a number of economically important species such as the Old World eggplants, as well as locally cultivated New World species such as the naranjilla and cocona. Given the size and importance of this group we have examined phylogenetic relationships across subgenus Leptostemonum, including a large sampling of species from previously defined species groups within the subgenus. Evolutionary relationships were inferred using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and one chloroplast spacer region (trnS-trnG). Results suggest that Solanum subgenus Leptostemonum is monophyletic when the S. wendlandii and S. nemorense species groups are excluded. We have defined 10 clades within subgenus Leptostemonum, some of which correspond to previously circumscribed species groups or sections. Most of the Old World species of subgenus Leptostemonumbelong to a single species-rich clade. Sharp prickles and/or stellate hairs evolved more than once in Solanum, and floral heterandry originated multiple times within the ‘‘spiny solanums.’’ waxy.

The "spiny solanums," Solanum subgenus Leptostemonum (Solanaceae), comprise a large lineage with over 350 species and include the cultivated eggplant, Solanum melongena. Despite the importance of this subgenus, phylogenetic relationships among these taxa are currently unclear. The present research contributes to this understanding while focusing on Solanum section Acanthophora, a group of ca. 19 species defined by the presence of simple hairs, rather than the stellate hairs common across the rest of subgenus Leptostemonum. In this study we inferred phylogenetic relationships among 29 Solanum taxa, including 14 species of section Acanthophora, using DNA sequence data from two nuclear regions (ITS and the granule-bound starch synthase gene [GBSSI or waxy]) and two chloroplast regions (trnT-trnF and trnS-trnG). This combination of gene regions resulted in a well resolved phylogenetic hypothesis, with results strongly suggesting that Solanum sect. Acanthophora is not monophyletic, although the majority of taxa comprise a monophyletic lineage that is sister to Solanum section Lasiocarpa. Of the four gene regions, waxy was especially useful for phylogenetic inference, with both a high percentage of parsimony-informative sites as well as a low level of homoplasy. Further studies in progress will help elucidate relationships of sect. Acanthophora with respect to other members of subgenus Leptostemonum.

We examined relationships between fragrance and phylogeny using a number of approaches to coding fragrance data and comparing the hierarchical information in fragrance data with the phylogenetic signal in a DNA sequence data set. We first used distance analyses to determine which coding method(s) best distinguishes species while grouping conspecifics. Results suggest that interspecific differences in fragrance composition were maximized by coding as presence/absence of fragrance compounds and biosynthetic pathways rather than when quantitative information was also included. Useful systematic information came from both compounds and pathways and from fragrance emitted by both floral and vegetative tissues. The coding methods that emerged from the distance analyses as best distinguishing species were then adapted for use in phylogenetic analysis. Although hierarchical signal among fragrance data sets was congruent, this signal was highly incongruent with the phylogenetic signal in the DNA sequence data. Notably, topologies inferred from fragrance data sets were congruent with the DNA topology only in the most distal portions (e.g., sister group pairs or closely related species that had similar fragrance profiles were often recovered by analyses of fragrance). Examination of consistency and retention indices for individual fragrance compounds and pathways as optimized onto one of the most-parsimonious trees inferred from DNA data revealed that although most compounds were homoplastic, some compounds were perfectly congruent with the DNA phylogeny. In particular, compounds and pathways found in a few taxa were less homoplastic than those found in many taxa. Pathways that synthesize few volatiles also seem to have lower homoplasy than those that produce many. Although fragrance data as a whole may not be useful in phylogeny reconstruction, these data can provide additional support for clades reconstructed with other types of characters. Factors other than phylogeny, including pollinator interactions, also likely influence fragrance composition. (Acleisanthes; character coding; four o'clocks; fragrance; Mirabilis; phylogenetics; scent; volatiles.)

GC-MS analyses of nocturnal and diurnal floral volatiles from nine tobacco species (Nicotiana; Solanaceae) resulted in the identification of 125 volatiles, including mono- and sesquiterpenoids, benzenoid and aliphatic alcohols, aldehydes and esters. Fragrance chemistry was species-specific during nocturnal emissions, whereas odors emitted diurnally were less distinct. All species emitted greater amounts of fragrance at night, regardless of pollinator affinity. However, these species differed markedly in odor complexity and emission rates, even among close relatives. Species-specific differences in emission rates per flower and per unit fresh or dry flower mass were significantly correlated; fragrance differences between species were not greatly affected by different forms of standardization. Flowers of hawkmoth-pollinated species emitted nitrogenous aldoximes and benzenoid esters on nocturnal rhythms. Four Nicotiana species in section Alatae sensu strictu have flowers that emit large amounts of 1,8 cineole, with smaller amounts of monoterpene hydrocarbons and alpha-terpineol on a nocturnal rhythm. This pattern suggests the activity of a single biosynthetic enzyme (1,8 cineole synthase) with major and minor products; however, several terpene synthase enzymes could contribute to total monoterpene emissions. Our analyses, combined with other studies of tobacco volatiles, suggest that phenotypic fragrance variation in Nicotiana is shaped by pollinator- and herbivore-mediated selection, biosynthetic pathway dynamics and shared evolutionary history.

Despite intensive morphological and molecular studies of Onagraceae, relationships within the family are not fully understood. One drawback of previous analyses is limited sampling within the large tribe Onagreae. In addition, the monophyly of two species-rich genera in Onagreae, Camissonia and Oenothera, has never been adequately tested. To understand relationships within Onagraceae, test the monophyly of these two genera, and ascertain the affinities of the newly discovered genus Megacorax, we conducted parsimony and maximum likelihood analyses with rbcL and ndhF sequence data for 24 taxa representing all 17 Onagraceae genera and two outgroup Lythraceae. Results strongly support a monophyletic Onagraceae, with Ludwigia as the basal lineage and a sister-taxon relationship between Megacorax and Lopezia. Gongylocarpus is supported as sister to Epilobieae plus the rest of Onagreae, although relationships within the latter clade have limited resolution. Thus, we advocate placement of Gongylocarpus in a monogeneric tribe, Gongylocarpeae. Most relationships within Onagreae are weakly resolved, suggesting a rapid diversification of this group in western North America. Neither Camissonia nor Oenothera appears to be monophyletic; however, increased taxon sampling is needed to clarify those relationships. Morphological characters generally agree with the molecular data, providing further support for relationships.