Document Actions
The resident endoplasmic reticulum prote ... -actin and myosin B heavy chain
The resident endoplasmic reticulum protein, BAP31, associates with gamma-actin and myosin B heavy chain
5394
BAP31 is a 28-kDa integral membrane protein of the endoplasmic reticulum whose cytosolic domain contains two caspase recognition sites that are preferentially cleaved by initiator caspases, such as caspase-8. Recently, we reported that the caspase-resistant BAP31 inhibited Fas-mediated apoptotic membrane fragmentation and the release of cytochrome c from mitochondria in KB epithelial cells (Nguyen M., Breckenridge G., Ducret A & Shore G. (2000) Mol. Cell. Biol.20, 6731-6740). We describe here the characterization by capillary liquid chromatography microelectrospray tandem MS of a BAP31 immunocomplex isolated from a HepG2 cell lysate in the absence of a death signal. We show that BAP31 specifically associates with nonmuscle myosin heavy chain B and nonmuscle gamma-actin, two components of the cytoskeleton actomyosin complex. Collectively, these data confirm that BAP31, in addition to its potential role as a chaperone, may play a fundamental role in the structural organization of the cytoplasm. Here we also show that Fas stimulation of apoptosis releases BAP31 associations with these motor proteins, a step that may contribute to extranuclear events, such as membrane remodelling, during the execution phase of apoptosis.
Ducret A, Nguyen M, Breckenridge DG, Shore GC
European journal of biochemistry / FEBS
2003-01-01 00:00
270
2
342-9
Actins,Actomyosin,Amino Acid Sequence,Chromatography, Liquid,Electrophoresis, Polyacrylamide Gel,Endoplasmic Reticulum,Humans,Membrane Proteins,Molecular Sequence Data,Myosin Heavy Chains,Nonmuscle Myosin Type IIB,Peptide Fragments,Precipitin Tests,Actins,BCAP31 protein, human,Membrane Proteins,Myosin Heavy Chains,Peptide Fragments,Actomyosin,Nonmuscle Myosin Type IIB,nonmuscle myosin type IIB heavy chain
Merck Frosst Center for Therapeutic Research, Pointe-Claire-Dorval, Québec, Canada. axel.ducret@roche.com
Eur. J. Biochem.
0014-2956
3395
0
False
12605685
