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Summary: Ecological theory predicts that early generation polyploids ('neopolyploids') should quickly go extinct owing to the disadvantages of rarity and competition with their diploid progenitors. However, polyploids persist in natural habitats globally. This paradox has been addressed theoretically by recognizing that reproductive assurance of neopolyploids and niche differentiation can promote establishment. Despite this, the direct effects of polyploidy at the population level remain largely untested despite establishment being an intrinsically population‐level process.We conducted population‐level experiments where life‐history investment in current and future growth was tracked in four lineage pairs of diploids and synthetic autotetraploids of the aquatic plant Spirodela polyrhiza. Population growth was evaluated with and without competition between diploids and neopolyploids across a range of nutrient treatments.Although neopolyploid populations produce more biomass, they reach lower population sizes and have reduced carrying capacities when growing alone or in competition across all nutrient treatments. Thus, contrary to individual‐level studies, our population‐level data suggest that neopolyploids are competitively inferior to diploids. Conversely, neopolyploid populations have greater investment in dormant propagule production than diploids.Our results show that neopolyploid populations should not persist based on current growth dynamics, but high potential future growth may allow polyploids to establish in subsequent seasons. [ABSTRACT FROM AUTHOR]

Premise: Whole‐genome duplication (neopolyploidy) can instantly differentiate the phenotype of neopolyploids from their diploid progenitors. These phenotypic shifts in organs such as roots and leaves could also differentiate the way neopolyploids interact with microbial species. While some studies have addressed how specific microbial interactions are affected by neopolyploidy, we lack an understanding of how genome duplication affects the diversity and composition of microbial communities. Methods: We performed a common garden experiment with multiple clones of artificially synthesized autotetraploids and their ancestral diploids, derived from 13 genotypes of wild strawberry, Fragaria vesca. We sequenced epiphytic bacteria and fungi from roots and leaves and characterized microbial communities and leaf functional traits. Results: Autotetraploidy had no effect on bacterial alpha diversity of either organ, but it did have a genotype‐dependent effect on the diversity of fungi on leaves. In contrast, autotetraploidy restructured the community composition of leaf bacteria and had a genotype‐dependent effect on fungal community composition in both organs. The most differentially abundant bacterial taxon on leaves belonged to the Sphingomonas, while a member of the Trichoderma was the most differentially abundant fungal taxon on roots. Ploidy‐induced change in leaf size was strongly correlated with a change in bacterial but not fungal leaf communities. Conclusions: Genome duplication can immediately alter aspects of the plant microbiome, but this effect varies by host genotype and bacterial and fungal community. Expanding these studies to wild settings where plants are exposed continuously to microbes are needed to confirm the patterns observed here. [ABSTRACT FROM AUTHOR]

Examines the subcellular localization of the transcription factor PHO4 in wild-type cells grown in low or high phosphate medium. Role of PHO4 in the induction of the PHO5 gene in response to phosphate starvation; Concentration of PHO4 in the nucleus; Sites of phosphorylation.

Shows that the activities of the pointed and yan Ets-related transcription factors required for normal eye development in Drosophila are regulated by the Ras1/MAPK pathway. Pointed gene coding for proteins; Yan function as negative regulator of photoreceptor determination; Yan repression activity regulation by the Ras1/MAPK signal.

Focuses on the role of cyclins and cyclin-dependent kinases (CDKs) in genetic transcriptional regulation. Presentation of model depicting possible interactions between specific SRB proteins and different promoter-selective factors.

Presents research which investigated how the export of the yeast transcription factor Pho4 is regulated in response to changes in phosphate availability. Regulation of activity between the nucleus and cytoplasm; Effects of the phosphorylation of a protein; Phosphorylation of Pho4; Use of the importin-beta-family member Msn5 by Pho4 as a shuttling receptor; Phosphorylation controlling the nuclear export of a protein.