title: Control of the actin cytoskeleton in root hair development.
abstract: The development of root hair includes four stages: bulge site selection, bulge formation, tip growth, and maturation. The actin cytoskeleton is involved in all of these stages and is organized into distinct arrangements in the different stages. In addition to the actin configuration, actin isoforms also play distinct roles in the different stages. The actin cytoskeleton is regulated by actin-binding proteins, such as formin, Arp2/3 complex, profilin, actin depolymerizing factor, and villin. Some upstream signals, i.e. calcium, phospholipids, and small GTPase regulate the activity of these actin-binding proteins to produce the proper actin configuration. We constructed a working model on how the actin cytoskeleton is controlled by actin-binding proteins and upstream signaling in root hair development based on the current literature: at the tip of hairs, actin polymerization appears to be facilitated by Arp2/3 complex that is activated by small GTPase, and profilin that is regulated by phosphatidylinositol 4,5-bisphosphate. Meanwhile, actin depolymerization and turnover are likely mediated by villin and actin depolymerizing factor, which are stimulated by calcium. At the shank, actin cables are produced by formin and villin. Under the complicated interaction, the actin cytoskeleton is controlled spatially and temporally during root hair development.
authors.affiliation: Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education and College of Life Science, Beijing Normal University, Beijing 100875, China.
authors.forename: Weike
authors.initials: W
authors.lastname: Pei
authors.forename: Fei
authors.initials: F
authors.lastname: Du
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Tian
authors.initials: T
authors.lastname: He
authors.forename: Haiyun
authors.initials: H
authors.lastname: Ren
mesh_terms: D051376:Actin-Related Protein 2-3 Complex / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D017360:Arabidopsis / Q000502:physiology* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D003599:Cytoskeleton / Q000502:physiology*; D051345:Destrin / Q000378:metabolism; D005326:Fetal Proteins / Q000378:metabolism; D000080865:Formins; D020558:GTP Phosphohydrolases / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000378:metabolism; D018517:Plant Roots / Q000502:physiology* / Q000648:ultrastructure; D051304:Profilins / Q000378:metabolism
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D000199:Actins; D029681:Arabidopsis Proteins; D051345:Destrin; D005326:Fetal Proteins; D000080865:Formins; D008840:Microfilament Proteins; D009687:Nuclear Proteins; D019269:Phosphatidylinositol 4,5-Diphosphate; D051304:Profilins; C026615:villin; D020558:GTP Phosphohydrolases; D002118:Calcium