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Lithium (Li), gallium (Ga) and indium (In) are industry-critical metals, with no known plant species that (hyper)accumulate these metals to any substantial degree. We hypothesised that sodium (Na) hyperaccumulators (i.e., halophytes) may accumulate Li, whilst aluminium (Al) hyperaccumulators may accumulate Ga and In, based on the chemical similarities of these elements. Experiments were conducted in hydroponics at various molar ratios for six weeks to determine accumulation in roots and shoots of the target elements. For the Li experiment, the halophytes Atriplex amnicola, Salsola australis and Tecticornia pergranulata were subjected to Na and Li treatments, whilst for the Ga and In experiment, Camellia sinensis was exposed to Al, Ga, and In. The halophytes were able to accumulate high shoot Li and Na concentrations reaching up to ~10 g Li kg−1 and 80 g Na kg−1, respectively. The translocation factors for Li were higher than for Na (about two-fold) in A. amnicola and S. australis. The results from the Ga and In experiment show that C. sinensis is capable of accumulating high concentrations of Ga (mean 150 mg Ga kg−1), comparable with Al (mean 300 mg Al kg−1), but virtually no In (

Azole resistance is a concern for the management of diseases caused by Aspergillus fumigatus in humans. Azole fungicide use in the environment has been identified as a possible cause for development of resistance, which increases the complexity and number of stakeholders involved in this emerging problem. A workshop was held in Amsterdam early 2019 in which stakeholders, including medical and agricultural researchers, representatives from the government, public health, fungicide producers and end-users, reviewed the current evidence supporting environmental selection for resistance and to discuss which research and measures are needed to retain the effectiveness of the azole class for environmental and medical applications. This paper provides an overview of the latest insights and understanding of azole resistance development in the clinical setting and the wider environment. A One Health problem approach was undertaken to list and prioritize which research will be needed to provide missing evidence and to enable preventive interventions.

Potato (Solanum tuberosum) is an important food crop consumed all over the world, but it is generally sensitive to drought conditions. One of the major physiological processes affected by drought stress is carbon partitioning: the plant's choice of where to allocate its photoassimilates. Our aim was to investigate the molecular factors and possible bottlenecks affecting carbon partitioning during drought. We studied potato cultivars with contrasting drought responses in the greenhouse in the years 2013–2015, and further investigated the expression of genes involved in carbon partitioning and metabolite levels. Our results indicate that one of the most severe effects of drought stress on potato is the arrest of stolon differentiation and formation of tubers. We also identified some physiological traits like stomatal conductance and chlorophyll content as affecting carbon assimilation, partitioning and eventual tuber yield. The gene expressions and biochemical analyses highlight the various tissues prioritized by the plant for assimilate transport during drought stress, and give indications of what distinguishes drought tolerance and sensitivity of cultivated potato. Some of the key genes studied (like Sucrose synthase and Sucrose transporters) may be inclusive breeding targets for drought tolerance in potato.

Sexually dimorphic traits in insects are subject to sexual selection, but our knowledge of the underlying molecular mechanisms is still scarce. Here we investigate how the highly conserved gene, Doublesex (Dsx), is involved in shaping sexual dimorphism in the model parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae). First, we present the revised Dsx gene structure including an alternative transcription start, and two additional male NvDsx transcript isoforms. We show sex-specific NvDsx expression and splicing throughout development, and demonstrate that transient NvDsx silencing in different male developmental stages shifts two sexually dimorphic traits from male to female morphology, with the effect being dependent on the timing of silencing. In addition, we determined the effect of NvDsx on the development of reproductive organs. Transient silencing of NvDsx in early male larvae affects the growth and differentiation of the internal and external reproductive tissues. We did not observe phenotypic changes in females after NvDsx silencing. Our results indicate that male NvDsx is required to suppress female-specific traits and/or to promote male-specific traits during distinct developmental windows. This provides new insights into the regulatory activity of Dsx during male wasp development in the Hymenoptera.

Symbiogenesis, literally ‘becoming by living together’, refers to the crucial role of symbiosis in major evolutionary innovations. The term usually is reserved for the major transition to eukaryotes and to photosynthesising eukaryotic algae and plants by endosymbiosis. However, in some eukaryote lineages endosymbionts have been lost secondarily, showing that symbiosis can trigger a major evolutionary innovation, even if symbionts were lost secondarily. This leads to the intriguing possibility that symbiosis has played a role in other major evolutionary innovations as well, even if not all extant representatives of such groups still have the symbiotic association. We evaluate this hypothesis for two innovations in termites (Termitoidae, also known informally as “Isoptera”): i) the role of flagellate gut protist symbionts in the transition to eusociality from cockroach-like ancestors, and ii) the role of non-gut associated symbionts in the transition to ‘higher’ termites, characterized by the absence of flagellate gut protists. In both cases we identify a crucial role for symbionts, even though in both cases, subsequently, symbionts were lost again in some lineages. We also briefly discuss additional possible examples of symbiogenesis. We conclude that symbiogenesis is more broadly applicable than just for the endosymbiotic origin of eukaryotes and photosynthetic eukaryotes, and may be a useful concept to acknowledge the important role of symbiosis for evolutionary innovation. However, we do not accept Lynn Margulis's view that symbiogenesis will lead to a paradigm shift from neoDarwinism, as the role of symbiosis in evolutionary change can be integrated with existing theory perfectly.

Workers in an ant colony can kill fungus-infected brood, thereby protecting the rest of the colony from fungal infection. This form of social immunity is analogous to the immune system of multicellular organisms where immune cells kill infected cells. Workers in an ant colony can kill fungus-infected brood, thereby protecting the rest of the colony from fungal infection. This form of social immunity is analogous to the immune system of multicellular organisms where immune cells kill infected cells.

Fermentation temperature is a crucial factor in the production of fermented dairy products. This study investigated the influence of fermentation temperature on physiochemical properties and the composition of the microbial communities of two types of mabisi: tonga and barotse mabisi. Mabisi is a traditionally fermented milk product made in Zambia by spontaneous fermentation of raw milk at ambient temperature. The two types of mabisi were produced with tonga mabisi fermented at 20, 22, 25 and 30 °C, and barotse mabisi at 25 and 30 °C. The pH, titratable acidity, syneresis, consistency, microbial community composition and aroma compounds were determined. We found that fermentation at 20 and 22 °C was slower than at 25 °C but they all produced tonga mabisi with medium acidity (pH 4.2) and ‘medium’ consistency within 48 h. Fermentation was most rapid at 30 °C but resulted in a product with a ‘thin’ consistency. Fermentation temperature did not affect the microbial community composition of tonga mabisi, which remained diverse and complex with Lactococcus as the dominant fermenting genus. However, in barotse mabisi, at 25 °C, the product had ‘thick’ consistency and the microbial community composition was dominated by Lactococcus whereas at 30 °C the product was thicker, more acidic and dominated by Lactobacillus.

Although frequently found on mounds of the grass-cutting termite genus . Trinervitermes, virtually nothing is known about the natural history of the fungal genus . Podaxis (Agaricaceae) nor why it associates with termite mounds. More than 40 species of this secotioid genus have been described since Linnaeus characterised the first species in 1771. However, taxonomic confusion arose when most of these species were reduced to synonymy with . Podaxis pistillaris in 1933. Although a few more species have since been described, the vast majority of specimens worldwide are still treated as . P. pistillaris. Using 45 fresh and herbarium specimens from Southern Africa, four from North America and one each from Ethiopia, and Kenya, we constructed the first comprehensive phylogeny of the genus. Four of the genotyped specimens were more than 100 y old. With the exception of the type specimen of . Podaxis rugospora, all herbarium specimens were labelled as . P. pistillaris or . Podaxis sp. However, our data shows that the genus contains at least five well-supported clades with significant inter-clade differences in spore length, width and wall thickness, and fruiting body length, supporting that clades likely represent distinct . Podaxis species. Certain clades consistently associate with termites while others appear entirely free-living.

Traditionally fermented beverages significantly contribute to food security in Africa. The nutritional and sensory quality characteristics of these beverages are closely linked to the different microorganisms they contain. We studied the effect of processing methods on the microbial composition of Munkoyo, a cereal-based fermented beverage, in three Zambian agroecological zones. In Choma, porridge was made from maize grits to which a watery extract from Rhynchosia roots was added as a source of enzymes. In Nyimba, maize meal was used to make porridge, in which Rhynchosia roots were submerged overnight. In Kitwe, porridge from maize meal was cooked until caramelization, followed by submersion of Rhynchosia roots. Irrespective of processing method, final pH was 2.5–3.5, with the lowest value for Nyimba. Presence and abundance of 16S rRNA encoding DNA sequences of the microorganisms showed no clear clustering on basis of the processing method but significantly affected the operational taxonomic unit (OTU) composition (anosim, R3,13 = 0.407, p < 0.05). The average Shannon indices, which indicate ecological diversity, were: Choma 1.14 ± 0.64, Nyimba 1.58 ± 0.23, and Kitwe 1.07 ± 0.95. Consequently, for industrial upscaling and quality standardization, specific combinations of different bacterial species can produce Munkoyo that addresses local consumer preferences.

Contains fulltext : 215617.pdf (Publisher’s version ) (Open Access) Opportunistic fungal pathogens can cause a diverse range of diseases in humans. The increasing rate of fungal infections caused by strains that are resistant to commonly used antifungals results in difficulty to treat diseases, with accompanying high mortality rates. Existing and newly emerging molecular resistance mechanisms rapidly spread in fungal populations and need to be monitored. Fungi exhibit a diversity of mechanisms to maintain physiological resilience and create genetic variation; processes which eventually lead to the selection and spread of resistant fungal pathogens. To prevent and anticipate this dispersion, the role of evolutionary factors that drive fungal adaptation should be investigated. In this review, we provide an overview of resistance mechanisms against commonly used antifungal compounds in the clinic and for which fungal resistance has been reported. Furthermore, we aim to summarize and elucidate potent generators of genetic variability across the fungal kingdom that aid adaptation to stressful environments. This knowledge can lead to recognizing potential niches that facilitate fast resistance development and can provide leads for new management strategies to battle the emerging resistant populations in the clinic and the environment. 01 november 2019

High affinity potassium transporters (HKT) are recognized as important genes for crop salt tolerance improvement. In this study, we investigated HvHKT1;5 as a candidate gene for a previously discovered quantitative trait locus that controls shoot Na+ and Na+/K+ ratio in salt-stressed barley lines on a hydroponic system. Two major haplotype groups could be distinguished for this gene in a barley collection of 95 genotypes based on the presence of three intronic insertions; a designated haplotype group A (HGA, same as reference sequence) and haplotype group B (HGB, with insertions). HGB was associated with a much stronger root expression of HKT1;5 compared to HGA, and consequently higher K+ and lower Na+ and Cl− concentrations and a lower Na+/K+ ratio in the shoots three weeks after exposure to 200 mM NaCl. Our experimental results suggest that allelic variation in the promoter region of the HGB gene is linked to the three insertions may be responsible for the observed increase in expression of HvHKT1;5 alleles after one week of salt stress induction. This study shows that in barley - similar to wheat and rice - HKT1;5 is an important contributor to natural variation in shoot Na+ exclusion.

Farming is done not only by humans, but also by some ant, beetle and termite species. With the discovery of a stingless bee farming a fungus that provides benefits to its larvae, bees can be added to this list.

Marker assisted plant breeding is a powerful technique for targeted crop improvement in horticulture and agriculture. It depends upon the correlation of desirable phenotypic characteristics with specific genetic markers. This can be determined by statistical models that relate the variation in the value of genetic markers to variation in phenotypic traits. It therefore depends upon the convergence of three technologies; the creation of genetically characterised (and thus marked) populations, high throughput screening procedures, and statistical procedures. While a large number of high throughput screening technologies are available, real-time screening techniques are usually based on some kind of imaging technologies, such as chlorophyll fluorescence imaging, that offers physiological data that are eminently suitable as a quantitative trait for genetic mapping.

Though inconspicuous in healthy nests, Pseudoxylaria species are almost always present and overgrow deteriorating fungus-growing termite gardens. Whether these fungi are detrimental to the fungus-garden, benign, or even beneficial is unclear. We hypothesize that Pseudoxylaria is a stowaway that practices a sit-and-wait strategy to survive in the termite nest. Using isolates from three different termite genera to test our hypothesis, we compared Pseudoxylaria’s growth on 40 carbon sources with that of Termitomyces and tested its interaction with Termitomyces. The C-source use of both fungi largely overlapped, indicating potential for competition. One-to-one interactions between Pseudoxylaria, Termitomyces and free-living relatives showed that Pseudoxylaria and Termitomyces strains interacted differently with each other than with each other’s free-living relatives. Both fungi grew less together than when growing alone, confirming that they compete. Pseudoxylaria was more strongly inhibited by Termitomyces than free-living Xylariaceae were. The results suggest that the symbiotic lifestyle adopted by Pseudoxylaria goes together with reduced antagonism towards Termitomyces, consistent with Pseudoxylaria being a stowaway.

Pollen of the European and Asian white birch (Betula pendula and B. platyphylla) causes hay fever in humans. The allergenic potency of other birch species is largely unknown. To identify birch trees with a reduced allergenicity, we assessed the immunochemical characteristics of 15 species and two hybrids, representing four subgenera within the genus Betula, while focusing on the major pollen allergen Bet v 1. Antigenic and allergenic profiles of pollen extracts from these species were evaluated by SDS-PAGE and Western blot using pooled sera of birch-allergic individuals. Tryptic digests of the Bet v 1 bands were analyzed by LC-MS(E) to determine the abundance of various Bet v 1 isoforms. Bet v 1 was the most abundant pollen protein across all birch species. LC-MS(E) confirmed that pollen of all species contained a mixture of multiple Bet v 1 isoforms. Considerable differences in Bet v 1 isoform composition exist between birch species. However, isoforms that are predicted to have a high IgE-reactivity prevailed in pollen of all species. Immunoblotting confirmed that all pollen extracts were similar in immune-reactivity, implying that pollen of all birch species is likely to evoke strong allergic reactions.

Two alleles of the het-s/S locus occur naturally in the filamentous fungus Podospora anserina, het-s and het-S. The het-s encoded protein can form a prion that propagates a self-perpetuating amyloid aggregate, resulting in two phenotypes for the het-s strains. The prion-infected [Het-s] shows an antagonistic interaction to het-S whereas the prion-free [Het-s*] is neutral in interaction to het-S. The antagonism between [Het-s] and het-S is seen as heterokaryon incompatibility at the somatic level and as het-S spore killing in the sexual cycle. Two different domains of the HET-s and HET-S proteins have been identified, and a structure-function relationship has been established for interactions at the somatic level. In this study, we correlate accumulation of the HET-s and HET-S proteins (visualized using GFP) during the sexual cycle with timing of het-S spore abortion. Also, we present the structure-function relationship of the HET-s domains for interactions in the sexual cycle. We show that the constructs that ensure het-s incompatibility function in somatic mycelium are also active in het-S spore killing in the sexual cycle. In addition, paternal prion transmission and het-S spore killing has been found with the HET-s(157-289) truncated protein. The consequences of the unique transition from a coenocytic to a cellular state in the sexual phase and the timing, and localization of paternal and maternal HET-s and HET-S expression that are pertinent to prion transmission, and het-S spore killing are elaborated. These data further support our previously proposed model for het-S spore killing.

Calorie restriction is the only life span extending regimen known that applies to all aging organisms. Although most fungi do not appear to senesce, all natural isolates of the modular filamentous fungus Podospora anserina have a limited life span. In this paper, we show that calorie restriction extends life span also in Podospora anserina. The response to glucose limitation varies significantly among 23 natural isolates from a local population in The Netherlands, ranging from no effect up to a 5-fold life span extension. The isolate dependent effect is largely due to the presence or absence of pAL2-1 homologous plasmids. These mitochondrial plasmids are associated with reduced life span under calorie restricted conditions, Suggesting a causal link. This has been substantiated using three combinations of isogenic isolates with and Without plasmids. A model is proposed to explain how pAL2-1 homologues influence the response to calorie restriction. (C) 2004 Elsevier Inc. All rights reserved.

Recent studies in yeast, animals and plants have provided major breakthroughs in unraveling the molecular mechanism of higher-order gene regulation. In conjunction with the DNA code, proteins that are involved in chromatin remodeling, histone modification and epigenetic imprinting form a large network of interactions that control the nuclear programming of cell identity. New insight into how chromatin conformations are regulated in plants sheds light on the relationships between chromosome function, cell differentiation and developmental patterns.

Beneficial mutations are intuitively relevant to understanding adaptation [1–3], yet not all beneficial mutations are of consequence to the long-term evolutionary outcome of adaptation. Many beneficial mutations—mostly those of small effect—are lost due either to (1) genetic drift [4, 5] or to (2) competition among clones carrying different beneficial mutations, a phenomenon called the "Hill-Robertson effect" for sexual populations [6] and "clonal interference" for asexual populations [7]. Competition among clones becomes more prevalent with increasing genetic linkage and increasing population size, and it is thus generally characteristic of microbial populations [8, 9]. Together, these two phenomena suggest that only those beneficial mutations of large fitness effect should achieve fixation, despite the fact that most beneficial mutations produced are predicted to have very small fitness effects [10, 11]. Here, we confirm this prediction—both empirically and theoretically—by showing that fitness effects of fixed beneficial mutations follow a distribution whose mode is positive.

Transcription controls active at the initial stages of meiosis are clearly key elements in the regulation of germinal differentiation. Transcription of the Sycp1 gene (synaptonemal complex protein 1) starts as early as the leptotene and zygotene stages. Constructs with Sycp1 5' upstream sequences directed the expression of reporter genes to pachytene spermatocytes in transgenic mice. A short fragment encompassing the transcription start (n.t. -54 to +102) was sufficient for stage-specific expression in the adult male and for temporal regulation during development. Upstream enhancer element(s) quantitatively regulating expression were localized in the region between -54 and -260. The gene is normally expressed both in the male and female gonads, but none of the promoter sequences active in the testis allowed the expression of reporter genes during meiosis in the ovary.

Which social insects rear their own food? Growing fungi for food has evolved twice in social insects: once in new-world ants about 50 million years ago; and once in old-world termites between 24 and 34 million years ago [1,2]. The termites domesticated a single fungal lineage — the extant basidiomycete genus Termitomyces — whereas the ants are associated with a larger diversity of fungal lineages (all basidiomycetes). The ants and termites forage for plant material to provision their fungus gardens.

Vegetative incompatibility, the prevention of somatic fusion between individuals, occurs frequently in ascomycetes. In all species studied, a large number of Vegetative Compatibility Groups (VCGs) is found. In this study the role of mutation rate, random genetic drift and selection for the evolution of these large numbers of VCGs are investigated, both analytically and by computer simulation. We find that, irrespective of selection, the product of population size and mutation rate for new VCGs has to be larger than one to get realistic numbers of VCGs in asexual populations. If the number of VCGs is large, selection does not lead to a significant increase in the number of VCGs. Sexual reproduction, however, may enlarge the number of VCGs, due to recombination of incompatiblity genes. Here strong selective pressure does give an extra increase in VCG numbers. These results suggest that vegetative incompatibility may be a selectively neutral trait, although that does not explain it s ubiquity. Finally, it can be crucial that fungi can live in extremely large populations. An extremely large population size may offer an alternative explanation for a high degree of polymorphism. This explanation does not apply for incompatibility systems of higher organisms.

Synaptonemal complexes (SCs) are zipper-like structures which are assembled between homologous chromosomes during the prophase of the first meiotic division. Their assembly and disassembly correlate with the successive chromatin rearrangements of meiotic prophase, namely the condensation, pairing, recombination and disjunction of homologous chromosomes. It was originally thought that SCs created the preconditions for the homologous crossing over of chromosomes by bringing corresponding parts of homologous chromosomes in close apposition. However, this view has been gradually undermined during recent years, and ideas about the roles of SCs have radically changed. SCs are now considered to be structures that both control the number and distribution of reciprocal exchanges between homologous chromosomes (cross-overs) and convert cross-overs into functional chiasmata. How SCs fulfil these roles remains to be elucidated.

Stem-cell spermatogonia of +/+, T70H translocation heterozygous and Ts(l 13 )70H tertiary trisomic mice were irradiated with various doses of X-rays. Blood lymphocytes of +/+ and Ts(l 13 )70H males were irradiated with 150 rad X-rays. Contrary to earlier findings (De Boer et al., 1977), tertiary trisomic mice with morphological abnormalities did not show an increased sensitivity for radiation-induced chromosome breaks. The yields of radiation-induced reciprocal translocations, scored in the primary spermatocytes, were equal for the +/+ and tertiary trisomic mice but were lower for the T70/+ males. Thus, no parallel could be established with the sensitivity of peripheral blood lymphocytes for the induction of dicentric chromosomes, where T70H/+ did not differ from +/+ mice (De Boer et al., 1977). Induced reciprocal translocations occured randomly over the late diplotene-early diakinesis and late diakinesis-metaphase I stages. Among the T70H/+ males (2 × 500 rad) there was no relation between the chiasma frequency per animal and the yield of induced translocations, though the translocation induction was positively correlated with the chiasma frequency on a per-cell basis. When all descendants of irradiated T70H spermatogonia were pooled, the induced translocation-originated multivalent contained more chiasmata in cells that had a higher chiasma score themselves. No relation could be found between the yield of induced translocations and the recovery of spermatogenesis after irradiation as expressed by the epididymal sperm count after 2 × 500 rad.