Inheritance of an Electrophoretic (<i>Es-7</i>) Variant of Chicken Liver Esterases

Abstract

The present study was carried out to detect new genetic variations of esterase isozymes of the chicken liver and to clarify the mode of inheritance of them. Horizontal starch gel electrophoresis was carried out for the separation of non-specific esterase isozymes. The electrode buffer containing 0.1M Tris (hydroxymethyl aminomethane) and 0.5M boric acid (pH 7.4), and the gel buffer which was made by dilution of the electrode buffer to a concentration of one twelfth were used. Hydrolyzed starch (Connaught) was used at a concentration of 12.7%. Electrophoresis was carried out at the constant current of 1.8mA per cm for 2-2.5 hours in a refrigerator at 3-7°C. Dyeing solution was the mixture of 40ml potassium phosphate buffer (pH 6.9) containing 50mg o-dianisidine tetrazotized, and 2ml acetone containing β-naphthyl acetate as the substrate.Starch gel electrophoresis of chicken liver extracts revealed the presence of three regions of esterase activity, which were designated I, II and III. New electrophoretic variants were observed in Region I (Fig. 1). The variants migrated a little faster than the electrophoretic band which was controlled by Es-4 locus, and were classified as arylesterases by the inhibitor studies (Table 1). Difference between the new variants and those by Es-4 was confirmed by comparisons using starch gel and agar gel electro-phoresis (Fig. 1-2). As the result of breeding tests, the variants were controlled by one autosomal locus with two alleles. The locus is designated Es-7 with alleles Es-7A and Es-7O. Es-7A was completely dominant to Es-7O.