Sema3b^tm1.2Brd

Exons 1-6, encoding the first 163 amino acids and ~40% of the SEMA domain, were flanked with loxP sites. An FRT-flanked puromycin resistance cassette was inserted into intron 6. ES cells were transfected with Cre to remove the floxed sequence containine exons 1-6. In situ hybridization of mutant embryos demonstrated lack of expression in rib primordial and regions of the head. RT-PCR showed transcripts from exons 7 and higher, though the transcripts do not have the full-length SEMA domain and therefore result in a functionally null protein. (J:97316)