IDENTIFICATION AND CHARACTERIZATION OF A LOW-TEMPERATURE REGULATED GENE ENCODING AN ACTIN-BINDING PROTEIN FROM WHEAT

A cDNA corresponding to a putative actin-binding protein was cloned fr om a cold-acclimated wheat cDNA library, The cDNA, designated Wcor719, encodes a polypeptide of 142 amino acids with a calculated molecular mass of 15.8 kDa and a pI of 4.27, The protein has the two conserved d omains identified as actin and phosphatidylinositol 4,5-biphosphate (P IP2) binding sites found in members of the cofilin family, Northern an alyses revealed that Wcor719 transcript accumulation is rapid and stro ngly up-regulated by low temperature, This accumulation was greater in the tolerant winter wheat and rye species compared to the less tolera nt ones, The rapidity of transcript induction and the significant homo logy with actin-binding proteins (ABP) from different organisms sugges t that the product of this gene might be involved in the dynamic reorg anization of the cytoskeleton during low temperature acclimation, It m ay also serve as a key factor in the signal transduction pathway durin g cold acclimation.