Arhgap42^{Gt(CE0477)Wtsi}

5' RACE revealed the gene trap cassette (beta-geo) is located in intron 3. Expressed mRNA was strongly but not completely depleted in all tissues evaluated indicating that this mutation results in a hypomorphic allele. Inclusion of the LacZ/neo insertion cassette into the aberrantly spliced transcript results in a heterologous protein that contains GRAF3 amino acids 1-104 fused in frame to the beta-Gal reporter gene. As expected, beta-Gal staining in gene trap mice closely mimicked endogenous gene expression with strong and selective staining within the heart, mesenteric, skeletal muscle and brain arterioles and the SMC layers of the GI tract. (J:221301)