ISSN:
0148-7280
Keywords:
calcium-modulated proteins
;
calmodulin
;
calmodulin-binding proteins
;
spermatozoa
;
membranes
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
Reproducible concentrations of calmodulin representing approximately 0.1% of the membrane protein were detected in purified plasma membranes from bovine epididymal spermatozoa. When membranes were isolated in the presence of 1 mM EGTA, the amount of calmodulin associated with the plasma membranes was not reduced. Calmodulin-binding proteins were detected in both purified plasma membranes and in a mixed membrane fraction containing both plasma membranes and cytoplasmic droplet membranes. A calcium-dependent, calmodulin-binding protein of apparent molecular weight 123,000 was detected in both fractions. In the presence of 1 mM EDTA, putative calcium-independent calmodulin-binding proteins of apparent molecular weights 93,000, 32,000, 18,000, and 15,000 were detected in the plasma membrane fraction. The 15,000 Mr polypeptide was also present in the mixed membrane fraction but the three proteins of higher molecular weight were reduced or absent in this fraction.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrd.1120110309
Permalink
