HUMAN DYNAMIN-LIKE PROTEIN INTERACTS WITH THE GLYCOGEN-SYNTHASE KINASE 3-BETA

Members of the dynamin superfamily are implicated in vesicle trafficki ng. Using human glycogen synthase kinase 3 beta (Gsk-3 beta) as bait i n the yeast two-hybrid system, we identified a novel human dynamin-lik e protein IV (HdynIV). When the full-length cDNA of HdynIV was sequenc ed, it showed that HdynIV's carboxyl terminal lacks a proline-rich dom ain that can bind to Gsk-3 beta. By Northern blot analysis and isoform -specific PCR, we found that HdynIV is expressed ubiquitously in all h uman tissues examined. Two transcripts of 2.4 and 4.4 kb are shown to be more abundant in heart, brain, and skeletal muscle. Interestingly, the 2.4-kb transcript is expressed more distinctly in the fetal liver than in the adult liver, suggesting that this protein might play a rol e during development. In the present report, we have demonstrated that HdynIV interacts with the Gsk-3 beta through its carboxyl-terminal re gion, implying that HdynIV may also be involved in cell signaling. (C) 1998 Academic Press.