Fanconi anemia group J protein is a protein that in humans is encoded by the BRCA1-interacting protein 1 (BRIP1) gene.[5][6][7]
Function
The protein encoded by this gene is a member of the RecQ DEAH helicase family and interacts with the BRCT repeats of breast cancer, type 1 (BRCA1). The bound complex is important in the normal double-strand break repair function of breast cancer, type 1 (BRCA1). This gene may be a target of germline cancer-inducing mutations.[7]
This protein also appears to be important in ovarian cancer where it seems to act as a tumor suppressor.[8] Mutations in BRIP1 are associated with a 10-15% risk of ovarian cancer.[9]
BRIP1 appears to have an important role in neuronal cells by suppressing oxidative stress, excitotoxicity induced DNA damage, and in protecting the integrity of mitochondria.[10] A deficiency of BRIP1 causes increased DNA damage, mitochondrial abnormalities and neuronal cell death.
DNA repair
BRIP1 protein is a DNA helicase that is employed in homologous recombinational repair, and in the response of the cell to DNA replication stress.[11] In part, BRIP1 carries out its function through interaction with other key DNA repair proteins, specifically MLH1, BRCA1 and BLM.[11] This group of proteins helps to ensuring genome stability, and in particular repairs DNA double-strand breaks during prophase 1 of meiosis.
Meiosis
During prophase I of meiosis in male mice, BRIP1 functions in the repair of DNA double-strand breaks, but does not appear to have a role in the formation of chromosomal crossovers.[12] BRIP1 co-localizes with TOPBP1 scaffold protein and the BRCA1 repair protein along chromosome cores starting early in meiotic prophase I forming discrete foci, and is also densely localized to the axes of unsynapsed chromosomes during the late zygonema (zygotene) stage of meiosis.[12]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Menichini P, Linial M (November 2001). "SUVi and BACH1: a new subfamily of mammalian helicases?". Mutation Research. 487 (1–2): 67–71. doi:10.1016/s0921-8777(01)00104-5. PMID11595410.
^Rafnar T, Gudbjartsson DF, Sulem P, Jonasdottir A, Sigurdsson A, Jonasdottir A, et al. (October 2011). "Mutations in BRIP1 confer high risk of ovarian cancer". Nature Genetics. 43 (11): 1104–1107. doi:10.1038/ng.955. hdl:2336/228034. PMID21964575. S2CID24535565.
^Ring KL, Garcia C, Thomas MH, Modesitt SC (November 2017). "Current and future role of genetic screening in gynecologic malignancies". American Journal of Obstetrics and Gynecology. 217 (5): 512–521. doi:10.1016/j.ajog.2017.04.011. PMID28411145. S2CID29024566.
^Mani C, Acharya G, Kshirsagar S, Vijayan M, Khan H, Reddy PH, Palle K (2022). "A Novel Role for BRIP1/FANCJ in Neuronal Cells Health and in Resolving Oxidative Stress-Induced DNA Lesions". Journal of Alzheimer's Disease. 85 (1): 207–221. doi:10.3233/JAD-215305. PMID34776453. S2CID244078679.
Karppinen SM, Vuosku J, Heikkinen K, Allinen M, Winqvist R (February 2003). "No evidence of involvement of germline BACH1 mutations in Finnish breast and ovarian cancer families". European Journal of Cancer. 39 (3): 366–371. doi:10.1016/S0959-8049(02)00498-7. PMID12565990.
Rutter JL, Smith AM, Dávila MR, Sigurdson AJ, Giusti RM, Pineda MA, et al. (August 2003). "Mutational analysis of the BRCA1-interacting genes ZNF350/ZBRK1 and BRIP1/BACH1 among BRCA1 and BRCA2-negative probands from breast-ovarian cancer families and among early-onset breast cancer cases and reference individuals". Human Mutation. 22 (2): 121–128. doi:10.1002/humu.10238. PMID12872252. S2CID36167584.