Kitl^tm1Pbes

Exon 6 was replaced with a neomycin selection cassette. This alternatively spliced exon 6 encodes the major proteolytic cleavage site for the generation of the soluble encoded protein. Homozygous mice express only a transcript that encodes the transmembrane bound form. However, reduced levels of a soluble form of the encoded protein is found in serum of homozygous mice, suggesting that a secondary proteolytic cleavage site is used. (J:50150)