Search results for "BAX inhibitor 1"
showing 4 items of 4 documents
BAX inhibitor-1 is a Ca(2+) channel critically important for immune cell function and survival.
2015
The endoplasmic reticulum (ER) serves as the major intracellular Ca(2+) store and has a role in the synthesis and folding of proteins. BAX (BCL2-associated X protein) inhibitor-1 (BI-1) is a Ca(2+) leak channel also implicated in the response against protein misfolding, thereby connecting the Ca(2+) store and protein-folding functions of the ER. We found that BI-1-deficient mice suffer from leukopenia and erythrocytosis, have an increased number of splenic marginal zone B cells and higher abundance and nuclear translocation of NF-κB (nuclear factor-κ light-chain enhancer of activated B cells) proteins, correlating with increased cytosolic and ER Ca(2+) levels. When put into culture, purifie…
Bax Inhibitor-1-mediated Ca2+ leak is decreased by cytosolic acidosis
2013
Bax Inhibitor-1 (BI-1) is an evolutionarily conserved six-transmembrane domain endoplasmic reticulum (ER)-localized protein that protects against ER stress-induced apoptotic cell death. This function is closely connected to its ability to lower steady-state ER Ca2+ levels. Recently, we elucidated BI-1's Ca(2+)-channel pore in the C-terminal part of the protein and identified the critical amino acids of its pore. Based on these insights, a Ca(2+)-channel pore-dead mutant BI-1 (BI-1(D213R)) was developed. We determined whether BI-1 behaves as a bona fide H+/Ca2+ antiporter or as an ER Ca(2+)-leak channel by investigating the effect of pH on unidirectional Ca(2+)-efflux rates. At pH 6.8, wild-…
Bax inhibitor-1 is likely a pH-sensitive calcium leak channel, not a H+/Ca2+ exchanger.
2014
The endoplasmic reticulum (ER) plays a key role in the synthesis, folding, and sorting of proteins, and disturbances of this delicate system can cause cell death. The ER also serves as the major intracellular calcium (Ca(2+)) store, and release of Ca(2+) from this store controls diverse cellular functions. At the interface of both these functions of the ER is Bax inhibitor-1 (BI-1), an evolutionarily conserved multifunctional protein that mediates Ca(2+) efflux from the ER and protects against ER stress. Several mechanisms have been proposed to explain how BI-1 might mediate Ca(2+) efflux from the ER. Chang et al. present structural evidence that a bacterial homolog of BI-1, BsYetJ, is a pH…
Transmembrane BAX Inhibitor-1 Motif Containing Protein 5 (TMBIM5) Sustains Mitochondrial Structure, Shape, and Function by Impacting the Mitochondria…
2020
The Transmembrane Bax Inhibitor-1 motif (TMBIM)-containing protein family is evolutionarily conserved and has been implicated in cell death susceptibility. The only member with a mitochondrial localization is TMBIM5 (also known as GHITM or MICS1), which affects cristae organization and associates with the Parkinson&rsquo