Icos^tm1Mak

Most of exon 2 and all of exons 3 and 4 were replaced by a neomycin selection cassette inserted by homologous recombination. The deleted region encoded the putative Icosl binding site, the transmembrane domain, and a portion of the intracellular domain including the YMFM motif that potentially binds lipid phosphotidylinositol 3 kinase. Flow cytometric analysis indicated an absence of protein on the surface of activated T cells obtained from homozygous mutant mice. (J:66702)