Cst3^tm1Karl

An attempted knockin resulted in the generation of a null mouse. The majority of exon 1 was replaced by a human Cst3 cDNA fragment containing a missense mutation that substitutes a glutamine for a leucine at codon 68. In addition, a neomycin selection cassette was inserted at the 3' end of exon 1 and replaced two thirds of intron 1. Northern blot analysis using probes for both the human and mouse transcript showed an absence of both transcripts in lung, heart, testis, kidney and brain tissues obtained from homozygous mutant mice. ELIZA using human- and mouse-specific antibodies failed to detect either protein in homozygous mutant animals. (J:62407)