Abstract

The {460}-tubulins and β-tubulins are the major constituents of microtubules which have long been recognized as important structural elements in cell growth and morphogenesis and more recently have been recognized for their role in regulation and signal transduction. They are known to serve as a template for protein-protein interactions and to facilitate or retard the movement of signaling proteins within the cell. Small gene families encode tubulins in plants and animals and the composition of microtubules with respect to the relative abundance of tubulins encoded by different gene family members is thought to change in response to various stimuli including environmental stress. We have identified 15 full-length cDNAs for the members of the {460}-tubulin gene family in hexaploid bread wheat ( Triticum aestivum L. ). The genes can be clustered into five homeologous groups of three genes each with high similarity to one the five members of the gene family in barley ( Hordium vulgare L. ) a closely related diploid species. Five members of the gene family, representing each of the five homeologous groups were found to be regulated at the level of mRNA during cold acclimation, each with a different pattern of expression. Representatives of five homeologous groups were mapped to chromosome arms using wheat chromosome deletion stocks.