Anti-Cyclin E2

Cyclin E was first identified by its ability to rescue growth of yeast deficient in G1 Cyclins, indicating a role in G1 or G1/S transitions.  Over-expression of Cyclin E has been observed in a variety of human tumors. Multiple isoforms of Cyclin E are expressed in tumors but not in normal tissues, suggesting a post-transcriptional regulation of Cyclin E.  Cyclin E2 associates with Cdk2 in a functional kinase complex that is inhibited by both p27Kip1 and p21Cip1.  The catalytic activity associated with Cyclin E2 complexes is cell cycle regulated and peaks at the G1/S transition.  Unlike Cyclin E1, which is expressed in most proliferating normal and tumor cells, Cyclin E2 levels were low to undetectable in non-transformed cells and increased significantly in tumor-derived cell