• 1 January 1978
    • journal article
    • research article
    • Vol. 90 (4), 725-734
Abstract
A difference in the heat-inactivation kinetics between the .beta.-glucuronidases of C3HeB/FeJ and C57B1/6J mice was utilized to assess the mode of action of a temporal genetic element in controlling the expression of the .beta.-glucuronidase structural gene Gus. The heat-inactivation kinetics of liver and kidney .beta.-glucuronidase from F1 C3HeB/FeJ .times. C57B1/6J animals were intermediate with respect to the parental enzyme patterns, suggesting that equal concentrations of the 2 allelic products were present in .beta.-glucuronidase tetramers of F1 progeny. .beta.-glucuronidase heteropolymers assembled in vivo under conditions where equal concentrations of the 2 structural alleles of the enzyme were present exhibited intermediate heat-inactivation kinetics. A trans mode of action of a genetic element that controls the rate of murine .beta.-glucuronidase synthesis is indicated.