transforming growth factor beta ( tgf-beta ) , a potent modulator of cell growth , differentiation , and the expression of extracellular matrix components in a variety of cell types , exists as two distinct homodimers ( tgf-beta 1 and tgf-beta 2 ) , sharing 71 % sequence homology .
C0007589
differentiation
C1366557
tgf-beta 1