RT Journal Article
SR Electronic
T1 ADF Proteins Are Involved in the Control of Flowering and Regulate F-Actin Organization, Cell Expansion, and Organ Growth in Arabidopsis
JF The Plant Cell
JO Plant Cell
FD American Society of Plant Biologists
SP 1333
OP 1346
DO 10.1105/TPC.010051
VO 13
IS 6
A1 Dong, Chun-Hai
A1 Xia, Gui-Xian
A1 Hong, Yan
A1 Ramachandran, Srinivasan
A1 Kost, Benedikt
A1 Chua, Nam-Hai
YR 2001
UL http://www.plantcell.org/content/13/6/1333.abstract
AB Based mostly on the results of in vitro experiments, ADF (actin-depolymerizing factor) proteins are thought to be key modulators of the dynamic organization of the actin cytoskeleton. The few studies concerned with the in vivo function of ADF proteins that have been reported to date were performed almost exclusively using single-cell systems and have failed to produce consistent results. To investigate ADF functions in vivo and during the development of multicellular organs, we generated transgenic Arabidopsis plants that express a cDNA encoding an ADF protein (AtADF1) in the sense or the antisense orientation under the control of a strong constitutively active promoter. Selected lines with significantly altered levels of AtADF protein expression were characterized phenotypically. Overexpression of AtADF1 resulted in the disappearance of thick actin cables in different cell types, caused irregular cellular and tissue morphogenesis, and reduced the growth of cells and organs. In contrast, reduced AtADF expression promoted the formation of actin cables, resulted in a delay in flowering, and stimulated cell expansion as well as organ growth. These results are consistent with the molecular functions of ADF as predicted by in vitro studies, support the global roles of ADF proteins during the development of a multicellular organism, and demonstrate that these proteins are key regulators of F-actin organization, flowering, and cell and organ expansion in Arabidopsis.