A gene trap vector, pGT1TMpfs, including a Betagalactosidase and a neomycin-resistance gene was inserted into the locus in intron 7, downstream of the C1 domain. The transcript resulting from the event encoded a fusion protein of the N-terminal sequence of the locus up to the C1 domain, followed by a TM domain and the beta-geo gene trap vector. (J:98314)