Open AccessPolymorphism of α‐actinin from human blood platelets Homodimeric and heterodimeric forms
Author(s) -
CACHE Yannick,
LANDON Françoise,
OLOMUCKI Anna
Publication year - 1984
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1984.tb08156.x
Subject(s) - protein subunit , sodium dodecyl sulfate , platelet , gel electrophoresis , chemistry , protease , biochemistry , microbiology and biotechnology , actinin , gene isoform , actin , enzyme , biology , gene , cytoskeleton , cell , immunology
In purified solutions of α‐actinin from human blood platelets, three polypeptides a, b and c , of approximately 100 kDa, were observed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. They were identified as α‐actinin subunits on the basis of their cross‐reactivity with antibodies against skeletal muscle α‐actinin and their interaction with F‐actin. After electrophoresis in the absence of sodium dodecyl sulfate, six forms were observed: aa, ab, bb, ac, bc, cc. The similarity between the one‐dimensional peptide maps of a and b and the absence of b in the presence of calcium‐dependent protease inhibitors indicated that b is probably derived from the a subunit. The c subunit differs from the a subunit. The results provide evidence that there are actually only two platelet α‐actinin subunits a and c which give rise to three isoforms: two homodimers aa and cc , and one heterodimer ac.