{"title":"The RhoGEF protein Plekhg5 self-associates via its PH domain to regulate apical cell constriction.","authors":"Ivan K Popov, Jiahui Tao, Chenbei Chang","doi":"10.1091/mbc.E24-04-0179","DOIUrl":null,"url":null,"abstract":"<p><p>RhoGEFs are critical activators of Rho family small GTPases and regulate diverse biological processes, such as cell division and tissue morphogenesis. We reported previously that the RhoGEF gene <i>plekhg5</i> controls apical constriction of bottle cells at the blastopore lip during <i>Xenopus</i> gastrulation, but the detailed mechanism of <i>plekhg5</i> action is not understood in depth. In this study, we show that localization of Plekhg5 in the apical cortex depends on its N-terminal sequences and intact guanine nucleotide exchange activity, whereas the C-terminal sequences prevent ectopic localization of the protein to the basolateral compartment. We also reveal that Plekhg5 self-associates via its PH domain, and this interaction leads to functional rescue of two mutants that lack the N-terminal region and the guanine nucleotide exchange factor activity, respectively, in trans. A point mutation in the PH domain corresponding to a variant associated with human disease leads to loss of self-association and failure of the mutant to induce apical constriction. Taken together, our results suggest that PH-mediated self-association and N-terminal domain-mediated subcellular localization are both crucial for the function of Plekhg5 in inducing apical constriction.</p>","PeriodicalId":18735,"journal":{"name":"Molecular Biology of the Cell","volume":" ","pages":"ar134"},"PeriodicalIF":3.1000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11481697/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular Biology of the Cell","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1091/mbc.E24-04-0179","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/8/28 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
RhoGEFs are critical activators of Rho family small GTPases and regulate diverse biological processes, such as cell division and tissue morphogenesis. We reported previously that the RhoGEF gene plekhg5 controls apical constriction of bottle cells at the blastopore lip during Xenopus gastrulation, but the detailed mechanism of plekhg5 action is not understood in depth. In this study, we show that localization of Plekhg5 in the apical cortex depends on its N-terminal sequences and intact guanine nucleotide exchange activity, whereas the C-terminal sequences prevent ectopic localization of the protein to the basolateral compartment. We also reveal that Plekhg5 self-associates via its PH domain, and this interaction leads to functional rescue of two mutants that lack the N-terminal region and the guanine nucleotide exchange factor activity, respectively, in trans. A point mutation in the PH domain corresponding to a variant associated with human disease leads to loss of self-association and failure of the mutant to induce apical constriction. Taken together, our results suggest that PH-mediated self-association and N-terminal domain-mediated subcellular localization are both crucial for the function of Plekhg5 in inducing apical constriction.
期刊介绍:
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