ISSN:
1573-4919
Keywords:
mitochondria
;
cyclosporin
;
cyclophilin
;
channels
;
permeability
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract Mitochondria possess an inner membrane channel, the permeability transition pore, which is inhibited by cyclosporin A (CBA) and by matrix protons. As suggested recently by our laboratory, pore closure by these inhibitors may be due to dissociation of mitochondrial cyclophilin (CyP-M), a matrix peptidyl-prolyl-cis-trans isomerase, from its putative binding site on the pore. Unbinding of CyP-M would follow a CsA-dependent or proton-dependent change in conformation of the CyP-M molecule. It is interesting that upon binding of CsA the enzymatic activity of CyP-M is inhibited, but it is not clear whether this event plays a role in pore inhibition. Here we report experiments designed to further test the role of CyP-M in pore function. Our results indicate that CyP-M-dependent and independent mechanisms of pore activation may exist, and that the peptidylprolyl-cis-trans-isomerase activity of CyP-M is not necessarily involved in pore modulation by CyP-M. (Mol Cell Biochem 174: 181–184, 1997)
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1006887921810
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