Rbm is a male infertility gene located in the AZFb region of the Y chromosome. Expression pattern of Rbm indicates that Rbm is critical for early phase of male germ cell development. It shares strong structural homology with hnRNP G, suggesting a function as an RNA processing factor. In order to gain a clue on the molecular mechanisms of Rbm on male germ cell development, we examined interactions of Rbm with selected proteins in yeast. The results revealed specific interactions between Rbm, hnRNP K and Tra2${alpha}$. These results suggest that hnRNP K and Tra2${alpha}$ may be functional partners of Rbm in male germ cells. We propose a model in which hnRNP K may playa role as a platform for Rbm and Tra2${alpha}$.