TMBIM6

TMBIM6, also known as Bax inhibitor-1 or BI-1, is a protein-coding gene that belongs to the transmembrane Bax inhibitor motif-containing (TMBIM) family. The TMBIM6 gene encodes an integral membrane protein of the endoplasmic reticulum (ER) and is expected to contribute to cellular homeostasis by modulating responses to stress.

The protein is predicted to contain six transmembrane helices, with the N- and C- termini facing the cytosol. Its ER localization places it at the center of pathways that govern cell survival, calcium signaling, and the unfolded protein response.

Functionally, TMBIM6 acts as an anti-apoptotic factor. It helps protect cells from stress-induced death by modulating ER calcium dynamics and ER stress signaling, which can influence the initiation of apoptosis. BI-1 is thought to dampen calcium leak from the ER, in part through interactions with calcium channels, and it can interact with members of the BCL-2 family, linking ER-based signals to mitochondrial pathways of life and death. In addition to its role in apoptosis, TMBIM6 may participate in related processes such as autophagy and cellular adaptation to ER stress.

Expression of TMBIM6 is widespread, with detectable levels in many tissues, and is influenced by cellular stress and signaling cues. Dysregulation of TMBIM6 has been described in various contexts, including cancer and neurodegenerative or inflammatory conditions, where altered cell survival and calcium homeostasis are relevant.

Overall, TMBIM6 is a conserved ER membrane protein that contributes to cell survival by regulating calcium homeostasis and ER stress responses. Because of its role in apoptosis and calcium signaling, it is a subject of interest in studies of disease mechanisms and potential therapeutic strategies.