Working group session:
Functional Genomics
Presentation type:
poster
Authors:
Lv, Fenni; Guo, Wangzhen
Presenter:
Lv, Fenni
Correspondent:
Guo, Wangzhen
Abstract:
Fiber cell initiation and elongation is critical for cotton fiber development. Previously, three cotton fiber-expressed genes (CFEs), GhCFE1, GhCFE2, and GhCFE3, were isolated and submitted to the genebank; however, the in vivo function of CFEs during cotton fiber development still remains unknown. Here, we characterized a gene which is originated from A-genome species and homeologous to GhCFE1 from D-genomes, so we named it GhCFE1A and designated GhCFE1 as GhCFE1D thereafter. GhCFE1 is preferentially expressed at initiation and rapid elongation stages in the developing fibers, in addition, much higher expression of GhCFE1 was detected at fiber initiation stage in the fiberless cotton mutants than that in TM-1. Interestingly, overexpression of GhCFE1A in cotton not only delayed fiber cell elongation but also significantly reduced the density of lint and fuzz fiber initials and stem trichomes. Further yeast two-hybrid assay showed that GhCFE1A interacts with at least four actin isoforms, and the interaction requires two conserved domains in GhCFE1A with unknown function, DUF761 and DUF4408. Moreover, actin staining and quantitative assay revealed reduced intensity of F-actin at rapid elongation stage in GhCFE1A-overexpressiong fibers. Taken together, the results demonstrated that GhCFE1A interacts with actin cytoskeleton and negatively regulates fiber cell initiation and elongation during cotton fiber development.