Transmembrane protein 39B (TMEM39B)

Transmembrane protein 39B (TMEM39B) is a multi-pass membrane protein consisting of eight transmembrane domains, primarily localized to the plasma membrane and vesicles in humans[1]. TMEM39B is moderately expressed in most human tissues, with especially high expression in testis, placenta, immune cells, adrenal gland, thymus, and fetal brain[1]. Knockdown studies highlight roles in autophagy regulation during viral infection and in the survival of virus-infected cells, as well as possible involvement in cellular stress responses such as DNA damage repair (notably demonstrated for the zebrafish ortholog)[1][2]. TMEM39B has also been implicated as a prognostic biomarker in certain B cell lymphomas, but its precise molecular function in humans remains incompletely characterized[1]. It is a member of a conserved protein family that, based on data from invertebrates and its paralog TMEM39A, may be involved in endoplasmic reticulum (ER) protein trafficking and collagen secretion, although this has not been conclusively demonstrated for TMEM39B itself[3][1]. There are currently no known drugs targeting TMEM39B, nor clinical data about its therapeutic modulation[1]. **Key points:** - Not classified as a classical therapeutic target such as a receptor, transporter, or ion channel[1]. - Serves as a biomarker, particularly in oncology (lymphoma prognosis), but without established mechanistic drug interaction or safety concerns at present[1]. - Functions may include vesicular trafficking, autophagy regulation during viral infection, and cellular stress response; probable evolutionary conservation of roles in ER homeostasis and possibly collagen secretion based on studies of related TMEM39 family proteins[1][2][3].

Other names

TMEM39BFLJ10315