Polymerase DNA Directed Beta (POLb)

DNA polymerase beta maintains genome integrity by participating in base excision repair. Over expression of POLB mRNA has been correlated with a number of cancer types whereas deficiencies in POLB results in hypersensitivity to alkylating agents, induced apoptosis and chromosomal breaking therefore it is essential that POLB expression is tightly regulated.

POLB gene is upregulated by CREB1 transcription factor binding to the cAMP response element(CRE) present in the promoter of the POLB gene in response to exposure to alkylating agents. POLB gene expression is also regulated at the post transcriptional level as the 3’UTR of the POLB mRNA has been shown to contain three stem-loop structures that influence gene expression.