Gametocyte-specific factor 1 (GTSF1)

Gametocyte-specific factor 1 (GTSF1) is a highly conserved protein of 167 amino acids containing two CHHC-type zinc-finger domains, primarily expressed in germ cells, and essential for their development and maintenance. GTSF1 acts as a co-factor in the piRNA pathway by binding to PIWI proteins, ensuring efficient silencing of genomic transposable elements and maintenance of DNA integrity in germline cells. In mammals, loss of GTSF1 function leads to defective piRNA biogenesis, derepression of retrotransposons, and infertility due to germ cell loss and meiotic arrest. In certain cancers, altered expression of GTSF1 has been observed, indicating potential utility as a biomarker. Though crucial to fertility and genome integrity, GTSF1 is not currently targeted by any approved drugs, and its molecular role is predominantly regulatory rather than enzymatic or signal transductive.

Other names

FAM112BCue110Protein FAM112BAsterix (in Drosophila)Family with sequence similarity 112, member BFLJ32942

Binds PIWI proteins, enhances piRNA biogenesis, mediates silencing of retrotransposons through chromatin modification and RNA cleavage. In some species, drives assembly of RNA-dependent silencing complexes.