Figure 1. Disruption of ESPL1 gene that encodes Separase protein (A) leads to the disruption of the C-terminal peptidase domain of the Separase protein.

Top, schematic of ESPL1 gene mutation by insertion of a gene trap vector, resulting in a truncated Separase protein is shown. Primer sets P1 and P3 are used to genotype the mice with mutant allele and P1 and P2 are used to genotype mice with the wild type allele. (B ), Western blot analysis of endogenous Separase protein from testis derived from the mutant mice and their wild type littermate controls (as indicated by the genotypes). ( C ), Densitometric quantification of Separase expression in the ESPL1^+/hyp mice compared to wild type after normalization to the expression of a housekeeping gene β-actin to compensate for loading control.