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71.
72.
Different Pathways Act Downstream of the CEP Peptide Receptor CRA2 to Regulate Lateral Root and Nodule Development 总被引:1,自引:0,他引:1
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María Pérez-Fernández Carole P. Elliott Alex Valentine José Antonio Oyola 《Journal of Plant Ecology》2019,12(6):949
Aims
Seeds ofRumex crispusfrom six provenances were studied in relation to their germination under drought and presence of nitrogen in the germination and emergence media. We also investigated whether adaptation to soil increases the ability of the species to colonize and establish in contrasting environments along a longitudinal gradient in western Spain by means of a reciprocal transplantation experiment. 相似文献
75.
Benjamin M. Moran Kosmas Hench Robin S. Waples Marc P. Hppner Carole C. Baldwin William Owen McMillan Oscar Puebla 《Molecular ecology》2019,28(11):2872-2885
Marine species tend to have extensive distributions, which are commonly attributed to the dispersal potential provided by planktonic larvae and the rarity of absolute barriers to dispersal in the ocean. Under this paradigm, the occurrence of marine microendemism without geographic isolation in species with planktonic larvae poses a dilemma. The recently described Maya hamlet (Hypoplectrus maya, Serranidae) is exactly such a case, being endemic to a 50‐km segment of the Mesoamerican Barrier Reef System (MBRS). We use whole‐genome analysis to infer the demographic history of the Maya hamlet and contrast it with the sympatric and pan‐Caribbean black (H. nigricans), barred (H. puella) and butter (H. unicolor) hamlets, as well as the allopatric but phenotypically similar blue hamlet (H. gemma). We show that H. maya is indeed a distinct evolutionary lineage, with genomic signatures of inbreeding and a unique demographic history of continuous decrease in effective population size since it diverged from congeners just ~3,000 generations ago. We suggest that this case of microendemism may be driven by the combination of a narrow ecological niche and restrictive oceanographic conditions in the southern MBRS, which is consistent with the occurrence of an unusually high number of marine microendemics in this region. The restricted distribution of the Maya hamlet, its decline in both census and effective population sizes, and the degradation of its habitat place it at risk of extinction. We conclude that the evolution of marine microendemism can be a fast and dynamic process, with extinction possibly occurring before speciation is complete. 相似文献
76.
Zhu Yaling Zhou Zhimin Huang Tao Zhang Zhen Li Wanbo Ling Ziqi Jiang Tao Yang Jiawen Yang Siyu Xiao Yanyuan Charlier Carole Georges Michel Yang Bin Huang Lusheng 《中国科学:生命科学英文版》2022,65(8):1517-1534
Science China Life Sciences - The limited knowledge of genomic noncoding and regulatory regions has restricted our ability to decipher the genetic mechanisms underlying complex traits in pigs. In... 相似文献
77.
Drosophila G9a is a nonessential gene 总被引:1,自引:1,他引:0
Mammalian G9a is a euchromatic histone H3 lysine 9 (H3K9) methyltransferase essential for development. Here, we characterize the Drosophila homolog of G9a, dG9a. We generated a dG9a deletion allele by homologous recombination. Analysis of this allele revealed that, in contrast to recent findings, dG9a is not required for fly viability. 相似文献
78.
Linster CL Gomez TA Christensen KC Adler LN Young BD Brenner C Clarke SG 《The Journal of biological chemistry》2007,282(26):18879-18885
The first committed step in the biosynthesis of L-ascorbate from D-glucose in plants requires conversion of GDP-L-galactose to L-galactose 1-phosphate by a previously unidentified enzyme. Here we show that the protein encoded by VTC2, a gene mutated in vitamin C-deficient Arabidopsis thaliana strains, is a member of the GalT/Apa1 branch of the histidine triad protein superfamily that catalyzes the conversion of GDP-L-galactose to L-galactose 1-phosphate in a reaction that consumes inorganic phosphate and produces GDP. In characterizing recombinant VTC2 from A. thaliana as a specific GDP-L-galactose/GDP-D-glucose phosphorylase, we conclude that enzymes catalyzing each of the ten steps of the Smirnoff-Wheeler pathway from glucose to ascorbate have been identified. Finally, we identify VTC2 homologs in plants, invertebrates, and vertebrates, suggesting that a similar reaction is used widely in nature. 相似文献
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80.
Absalon S Kohl L Branche C Blisnick T Toutirais G Rusconi F Cosson J Bonhivers M Robinson D Bastin P 《PloS one》2007,2(5):e437
To perform their multiple functions, cilia and flagella are precisely positioned at the cell surface by mechanisms that remain poorly understood. The protist Trypanosoma brucei possesses a single flagellum that adheres to the cell body where a specific cytoskeletal structure is localised, the flagellum attachment zone (FAZ). Trypanosomes build a new flagellum whose distal tip is connected to the side of the old flagellum by a discrete structure, the flagella connector. During this process, the basal body of the new flagellum migrates towards the posterior end of the cell. We show that separate inhibition of flagellum assembly, base-to-tip motility or flagella connection leads to reduced basal body migration, demonstrating that the flagellum contributes to its own positioning. We propose a model where pressure applied by movements of the growing new flagellum on the flagella connector leads to a reacting force that in turn contributes to migration of the basal body at the proximal end of the flagellum. 相似文献