The Genetic Control of Three Kidney Esterases in C57bl/6j and Rf/J Mice.

recent years considerable interest has developed in the genetic control of ';rotein determination in metazoan species. In the house mouse the genetic specification of histocompatibility antigens (SNELL 1963; KLEIN 1963), gammaglobulin (HERZENBERG, MISHELL, and HERZENBERG 1963), and hemoglobins (RUSSELL and GERALD 1958; POPP 1963) have been carefully studied, and a number of distinct mutant forms of these proteins have been described. The inheritance of another class of proteins-the enzymes-has been studied, and a number of mutant forms have been found. For example, SHAW and BARTO ( 1963) discovered a lactic dehydrogenase mutant in Peromyscus. Also, several serum esterase mutants have been reported by POPP and POPP (1962), and by PETRAS (1963), in the house mouse. Such mutant proteins can be detected by alterations in electrophoretic mobility, reaction rates, heat sensitivity, and sensitivity to chemical inhibitors. The work to be described here presents evidence for variant forms of soluble esterases extracted from mouse kidney tissue. It has been possible by means of starch gel electrophoresis to recognize two esterases, A and B, which are native to mouse strain RF/J, and an esterase C, native to C57BL/6J. By means of genetic analysis it has been possible to determine the nature of genetic control for esterases A and B, and preliminary evidence has been obtained for esterase C. In the majority of the experiments relating to the detection and description of enzyme mutants, sera or erythrocytes have been employed as an enzyme source. In the work described here, the esterases were extracted from adult mouse kidney tissues. Kidney was purposely selected, since this tissue can be cultivated in vitro. One of the major future aims in this work is the identification of enzyme mutants which can be used as genetic markers in vitro.