Testis-specific metallothionein-like protein (TESMIN)

Testis-specific metallothionein-like protein (TESMIN, encoded by the MTL5 gene) is a highly conserved, cysteine-rich, low-molecular-weight protein that binds heavy metal ions but does not have enzymatic activity[4][5]. It plays an essential role in male meiosis, spermatogenesis, and male fertility and is prominently expressed in testis but also detectable during meiotic prophase I in ovaries and heart[3][4][5]. TESMIN is considered a cell cycle–related protein and its expression is closely linked to the cell cycle, especially in germ cells. Elevated expression of TESMIN has been implicated as a prognostic biomarker in cancers such as lung adenocarcinoma, where high expression correlates with poor survival, high somatic mutation burden, and an immunosuppressive tumor microenvironment[1]. TESMIN-related gene networks are involved in cell division, and its presence can affect the response to chemotherapy and immunotherapy, making it a marker for pharmacogenomic sensitivity prediction, though it is not currently a direct therapeutic target[1][5][4].

Other names

TesminMTL5Metallothionein-like 5CXC domain containing 2CXCDC2testis expressed metallothionein like proteintestis-specific metallothionein-like proteinMTLT

Not established for any therapeutic drugs; binds metal ions such as copper and silver