HELB
Description
The HELB (DNA helicase B) is a protein-coding gene located on chromosome 12.
HELB is a 5'-3' DNA helicase that plays a crucial role in DNA damage response by inhibiting DNA end resection. Upon DNA damage, HELB is recruited to single-stranded DNA (ssDNA) and inhibits the activity of nucleases like EXO1, BLM, and DNA2, which are involved in DNA end resection. This inhibition is likely mediated by HELB's 5'-3' ssDNA translocase activity. As cells transition into the S phase, HELB is phosphorylated and exported from the nucleus, promoting DNA end resection. HELB functions independently of TP53BP1. It unwinds duplex DNA with a 5'-3' polarity and exhibits single-strand DNA-dependent ATPase and DNA helicase activities. HELB prefers ATP and dATP as substrates. During the S phase, HELB might facilitate the recovery of cells from replication stress. HELB interacts with RPA1, which enhances its recruitment to chromatin following DNA damage. It also interacts with at least two subunits of the DNA polymerase alpha complex: CDC45 and TOPB1.
HELB is also known as DHB, hDHB.
Associated Diseases
- FRAXF syndrome
- nemaline myopathy 5
- xeroderma pigmentosum
- skin pigmentation disorder
- hyperinsulinemic hypoglycemia, familial, 4
