title: Two-dimensional gel electrophoresis of cattle plasma proteins: genetic polymorphism of an alpha 1-protease inhibitor.
abstract: Two-dimensional electrophoretic analysis of cattle plasma proteins was done by a first dimension separation in agarose gel (pH 5.0), followed by a second dimension in horizontal polyacrylamide gel (pH 9.0). This method resulted in improved and reproducible separation of many alpha- and beta-globulins. Three groups of alpha-globulins, designated Pi-1, Pi-2 and Pi-3, were found to inhibit the esterolytic activity of bovine trypsin and bovine chymotrypsin. Pi-2 showed appreciable inhibition only for trypsin and genetic polymorphism was observed for this protein. Family data supported the hypothesis that the three Pi-2 types observed were controlled by two codominant, autosomal alleles. The occurrence of a third Pi-2 allele was also postulated in some animals studied. The frequency of the most common allele, Pi-2s, ranged from 0.5-0.8 in the different breeds of cattle studied (Swedish Red and White, Friesian, Jersey, Charolais and Simmental). The post-transferrins Ptf-1 and Ptf-2 in cattle plasma were shown to be two different genetic systems.
mesh_terms: D000818:Animals; D001798:Blood Proteins / Q000235:genetics*; D002417:Cattle / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005787:Gene Frequency; D005796:Genes; D008297:Male; D011110:Polymorphism, Genetic; D000515:alpha 1-Antitrypsin / Q000235:genetics
chemical_list: D001798:Blood Proteins; D000515:alpha 1-Antitrypsin