Cloning of dynein intermediate chain cDNA of the newt Cynops pyrrhogaster

To isolate genes whose expression is up-regulated after initiation of meios is, rye employed an mRNA differential display method using RNA extracted fr om newt testis fragments in the spermatogonial and spermatocyte stages. We report here isolation of a spermatocyte stage-specific cDNA clone encoding a newt homologue of dynein intermediate chain (IC). The newt dynein IC cDNA was found to encode a polypeptide consisting of 694 amino acid residues wi th 66.8% and 45.8% amino acid sequence similarity to sea urchin dynein IC3 and Chlamydomonas IC69, respectively;. The predicted protein contains five WD repeats and a novel repeated motif in the C-terminal region. Northern bl ot analysis revealed that newt dynein IC mRNA was expressed in the spermato cyte and round spermatid stages, suggesting that dynein IC plays a role in formation of flagella as well as in meiotic events.