Ptprc^tm1Holm

A neomycin resistance cassette, corrected for a point mutation believed to affect the transformation efficiency of ES cells, was used to disrupt exon 9, which is common to all of the isoforms. The mutation results in the introduction of several stop codons downstream of the insertion. FACS analysis using antibodies for multiple isoforms showed an absence of cell surface expression in homozygous mutant mice. A lack of encoded protein was further confirmed by Western blot analysis of thymus lysates. (J:33466)