Adapter protein able to interact with different proteins and involved in different biological processes. Mediates the interaction between the error-prone DNA polymerase zeta catalytic subunit rev3l and the inserter polymerase rev1, thereby mediating the second polymerase switching in translesion DNA synthesis. Translesion DNA synthesis releases the replication blockade of replicative polymerases, stalled in presence of DNA lesions. May also play a role in signal transduction in response to DNA damage. May regulate the activation of the anaphase promoting complex APC thereby regulating progression through the cell cycle. Through transcriptional regulation may play a role in epithelial-mesenchymal transdifferentiation 