STUDIES ON MUSCLE DIFFERENTIATION. VI. IMMUNOLOGICAL SPECIFICITY OF TROPOMYOSIN FROM CHICKEN SKELETAL MUSCLES *

Abstract

The chicken skeletal muscle tropomyosin preparation reacted in agar diffusion test with the anti-chicken skeletal muscle tropomyosin antiserum by forming three precipitin lines which were very close with one another and appeared to be almost a single precipitin line. Three antigens responsible for the formation of these three precipitin lines could not be differentiated in 8 m urea-polyacrylamide gel electrophoresis. These three precipitin lines could be identified to be due to the reaction between authentic tropomyosin molecules and their corresponding antibodies. Further, one of these three antigens was found to be present in the extracts from skeletal and cardiac muscles of various vertebrates so far tested and was identical with the genusand organ-nonspecific antigen as revealed earlier by the immunological study with frog skeletal muscle tropomyosin (Hirabayashi and Hayashi, 1970b). One of the remaining two antigens was clearly found to be present in the skeletal muscle extracts from avian sources. The last antigen was clearly found to be present in the extracts from pectoral and leg muscles, gizzard, anterior stomach, kidney, ovary, oviduct, testis and brain of the chicken. However, the reaction of the antibody against the last antigen with the extract of pectoral muscle of the chicken was very weak.