HELQ
Description
The HELQ (helicase, POLQ like) is a protein-coding gene located on chromosome 4.
HELQ is a single-stranded 3'-5' DNA helicase that plays a key role in homology-driven double-strand break (DSB) repair. HELQ is involved in different DSB repair mechanisms that are guided by annealing of extensive stretches of complementary bases at break ends, such as microhomology-mediated end-joining (MMEJ), single-strand annealing (SSA) or synthesis-dependent strand annealing (SDSA). HELQ possesses both DNA unwinding and annealing activities. HELQ forms a complex with RAD51, stimulating HELQ DNA helicase activity and ability to unwing DNA. HELQ efficiently unwinds substrates containing 3' overhangs or a D-loop. In contrast, interaction with the replication protein A (RPA/RP-A) complex inhibits DNA unwinding by HELQ but strongly stimulates DNA strand annealing. HELQ triggers displacement of RPA from single-stranded DNA to facilitate annealing of complementary sequences. {ECO:0000269|PubMed:11751861, ECO:0000269|PubMed:19995904, ECO:0000269|PubMed:21398521, ECO:0000269|PubMed:24005041, ECO:0000269|PubMed:24005565, ECO:0000269|PubMed:34316696, ECO:0000269|PubMed:34937945}
HELQ is also known as HEL308.
Associated Diseases
- 46,XY complete gonadal dysgenesis
- attenuated familial adenomatous polyposis
- 46,XX testicular disorder of sex development
- ovarian cancer
- Lynch syndrome
- gastric adenocarcinoma and proximal polyposis of the stomach
- hyperplastic polyposis syndrome
- gonadoblastoma
- ring chromosome Y
- thyroid cancer, nonmedullary, 4
- Muir-Torre syndrome
- 46,XY partial gonadal dysgenesis