Terminal nucleotidyltransferase 5D (TENT5D)

Terminal nucleotidyltransferase 5D (TENT5D) is a non-canonical, cytoplasmic poly(A) polymerase belonging to the TENT5/FAM46 family, encoded by the TENT5D (formerly FAM46D) gene on human chromosome X[1][4][5][13]. TENT5D adds adenosine residues to the poly(A) tail of mRNAs bearing a 3'-OH terminal group, preferentially polyadenylating transcripts for secreted and endoplasmic reticulum-targeted proteins, especially in male germ cells[3][7][8]. It is essential for spermatogenesis, and loss-of-function mutations or knockout of TENT5D cause oligoasthenoteratozoospermia or teratozoospermia, resulting in male infertility[2][3][6][9]. TENT5D is also expressed as a cancer/testis antigen, with detectable antibodies in the plasma of some cancer patients, suggesting a role as a candidate immunotherapy target[1][4][11]. Direct drug interactions have not been reported, and its function outside germ cells is still under investigation, but genetic and protein studies implicate it in critical reproductive and possibly oncogenic processes.

Other names

FAM46DMGC26999CT1.26CT112Non-canonical poly(A) polymerase FAM46Dcancer/testis antigen 112family with sequence similarity 46 member Dputative nucleotidyltransferase FAM46D

Immunotherapy: Design of antibodies against the TENT5D antigen to stimulate an immune response against cancer cells expressing this protein has been hypothesized. However, no clinically validated mechanism yet exists; this should remain null unless future studies provide evidence.