v-erb A and v-erb B do not cooperate in quail myoblasts.

We have previously shown that v-erb A stimulates quail myoblast differentiation in a T3 independent, cell-specific manner. In this work, we have studied the influence of v-erb B (the second oncogene carried in the AEV genome) upon quail myoblast proliferation and differentiation. v-erb B expression,moderately stimulates myoblast proliferation, and inhibits differentiation. Moreover, this oncoprotein fully inhibits the v-erb A myogenic influence. These data provide evidence that these two oncogenes do not cooperate in avian myoblasts. Consequently, in contrast to results obtained in other cell-types, coexpression of both oncogenes does not transform quail myoblasts.