DNA polymerase beta is the smallest among the eukaryotic DNA polymerases. It is typically described as a DNA repair enzyme, involved in various types of DNA repair such as Base Excision Repair (BER), Nucleotide Excision Repair (NER), post-replicative Mismatch Repair (MMR), and Double Strand Break Repair (DSBR). In eukaryotic cells, DNA polymerase beta (POLB) performs base excision repair (BER) required for DNA maintenance, replication, recombination, and drug resistance. Overexpression 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's binding to the cAMP response element (CRE) present in the promoter of the POLB gene in response to exposure to alkylating agents. This polymerase, due to its size, is a very "photogenic" structure. Here you can see a recent crystal structure of human DNA polymerase beta in complex with a synthetic DNA substrate (PDB code: 7S9M)
#molecularart ... #immolecular ... #DNA ... #polymerase ... #beta ... #smallpolymerase ... #crystal ... #xray ... #genomeintegrity
Structure of the DNA polymerase rendered with @proteinimaging and depicted with @corelphotopaint
#molecularart ... #immolecular ... #DNA ... #polymerase ... #beta ... #smallpolymerase ... #crystal ... #xray ... #genomeintegrity
Structure of the DNA polymerase rendered with @proteinimaging and depicted with @corelphotopaint
