An Update on Crop ABA Receptors

[EN] The hormone abscisic acid (ABA) orchestrates the plant stress response and regulates sophisticated metabolic and physiological mechanisms essential for survival in a changing environment. Plant ABA receptors were described more than 10 years ago, and a considerable amount of information is available for the model plant Arabidopsis thaliana. Unfortunately, this knowledge is still very limited in crops that hold the key to feeding a growing population. In this review, we summarize genomic, genetic and structural data obtained in crop ABA receptors. We also provide an update on ABA perception in major food crops, highlighting specific and common features of crop ABA receptors.This research was funded by the grants SP20180340 (PAID-06-18), from Universitat Politecnica de Valencia, and GV/2020/159, from Generalitat Valenciana, to J.L.-J. and FONDOCYT2018 2C1-182 grant from FONDOCYT to S.M.R. and J.L.-J.Ruiz-Partida, R.; Rosario, SM.; Lozano Juste, J. (2021). An Update on Crop ABA Receptors. Plants. 10(6):1-22. https://doi.org/10.3390/plants10061087S12210

Engineered Functional Redundancy Relaxes Selective Constraints upon Endogenous Genes in Viral RNA Genomes

[EN] Functional redundancy, understood as the functional overlap of different genes, is a double-edge sword. At the one side, it is thought to serve as a robustness mechanism that buffers the deleterious effect of mutations hitting one of the redundant copies, thus resulting in pseudogenization. At the other side, it is considered as a source of genetic and functional innovation. In any case, genetically redundant genes are expected to show an acceleration in the rate of molecular evolution. Here, we tackle the role of functional redundancy in viral RNA genomes. To this end, we have evaluated the rates of compensatory evolution for deleterious mutations affecting an essential function, the suppression of RNA silencing plant defense, of tobacco etch potyvirus (TEV). TEV genotypes containing deleterious mutations in presence/absence of engineered functional redundancy were evolved and the pattern of fitness and pathogenicity recovery evaluated. Genetically redundant genotypes suffered less from the effect of deleterious mutations and showed relatively minor changes in fitness and pathogenicity. By contrast, nongenetically redundant genotypes had very low fitness and pathogenicity at the beginning of the evolution experiment that were fully recovered by the end. At the molecular level, the outcome depended on the combination of the actual mutations being compensated and the presence/absence of functional redundancy. Reversions to wild-type alleles were the norm in the nonredundant genotypes while redundant ones either did not fix any mutation at all or showed a higher nonsynonymous mutational load.We thank Paula Agudo for excellent technical assistance. This work was supported by Spain's Agencia Estatal de Investigacion-FEDER grant BFU2015-65037-P to S.F.E. and by a fellowship from the Dominican Republic's Ministerio de Educacion Superior, Ciencia y Tecnologia to S.M.R. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the article.Ambros Palaguerri, S.; De La Iglesia Jordán, F.; Rosario, S.; Butkovic, A.; Elena Fito, SF. (2018). Engineered Functional Redundancy Relaxes Selective Constraints upon Endogenous Genes in Viral RNA Genomes. Genome Biology and Evolution. 10(7):1823-1836. https://doi.org/10.1093/gbe/evy141S1823183610