FOG-2: A novel GATA-family cofactor related to multitype zinc-finger proteins Friend of GATA-1 and U-shaped

GATA factors are transcriptional regulatory proteins that play critical rol es in the differentiation of multiple cell types in both vertebrates and in vertebrates. Recent evidence suggests that the biological activities of bot h mammalian and Drosophila GATA factors are controlled in part by physical interaction with multitype zinc-finger proteins, Friend of GATA-1 (FOG) and U-shaped (Ush), respectively. Here we describe a new FOG-related polypepti de, designated FOG-2, that is likely to participate in differentiation medi ated by GATA factors in several tissues, Expression of FOG-2 mRNA differs f rom that of FOG and is largely restricted to heart, neurons, and gonads in the adult. Somewhat broader expression is evident during mouse embryonic de velopment, Similar to FOG and Ush, FOG-2 protein interacts specifically wit h the amino finger of GATA factors in the yeast two-hybrid system and in ma mmalian cells. Remarkably, though FOG-2 is quite divergent from FOG in its primary sequence, forced expression of FOG-2 rescues terminal erythroid mat uration of FOG(-/-) hematopoietic cells, Thus, members of the FOG family of cofactors share highly specific association with GATA factors and are subs tantially interchangeable with respect to some aspects of function in vivo, The interaction of GATA and FOG family members constitutes an evolutionari ly conserved paradigm for transcrip tional control in differentiation and o rganogenesis.