title: A cotton annexin protein AnxGb6 regulates fiber elongation through its interaction with actin 1.
abstract: Annexins are assumed to be involved in regulating cotton fiber elongation, but direct evidence remains to be presented. Here we cloned six Annexin genes (AnxGb) abundantly expressed in fiber from sea-island cotton (G. barbadense). qRT-PCR results indicated that all six G. barbadense annexin genes were expressed in elongating cotton fibers, while only the expression of AnxGb6 was cotton fiber-specific. Yeast two hybridization and BiFC analysis revealed that AnxGb6 homodimer interacted with a cotton fiber specific actin GbAct1. Ectopic-expressed AnxGb6 in Arabidopsis enhanced its root elongation without increasing the root cell number. Ectopic AnxGb6 expression resulted in more F-actin accumulation in the basal part of the root cell elongation zone. Analysis of AnxGb6 expression in three cotton genotypes with different fiber length confirmed that AnxGb6 expression was correlated to cotton fiber length, especially fiber elongation rate. Our results demonstrated that AnxGb6 was important for fiber elongation by potentially providing a domain for F-actin organization.
authors.affiliation: Plant Biotechnology Research Center, SJTU-Cornell Institute of Sustainable Agriculture and Biotechnology, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Yiqun
authors.initials: Y
authors.lastname: Huang
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Lida
authors.initials: L
authors.lastname: Zhang
authors.forename: Kaijing
authors.initials: K
authors.lastname: Zuo
mesh_terms: D000199:Actins / Q000378:metabolism*; D021581:Active Transport, Cell Nucleus; D000595:Amino Acid Sequence; D017302:Annexins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development; D002462:Cell Membrane / Q000378:metabolism; D002466:Cell Nucleolus / Q000378:metabolism; D032561:Cotton Fiber; D018506:Gene Expression Regulation, Plant; D003368:Gossypium / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development; D011485:Protein Binding; D013379:Substrate Specificity
chemical_list: D000199:Actins; D017302:Annexins; D010940:Plant Proteins