Protein synthesis in human platelets.

The platelets and leukocytes of human peripheral blood were separated and cultured for 24 h in the same medium. The culture medium was completed with S-methionine. The overall protein synthetic activity of the platelets, compared with leukocytes, was studied with a two-dimensional gel electrophoresis technique combined with fluorographic detection of labelled proteins. Our findings confirm the platelet-origin of a few newly synthesized proteins. The most pronounced newly synthesized platelet protein with a molecular weight of approximately 35 Kda and with a more acidic isoelectric point than that of actin was identified as a cytoskeleton-associated protein.