LoxP sites were placed on either side of the exons that encode for the S5/S6 transmembrane domains of the gene followed by an FRT-flanked self-excising neomycin resistance cassette placed in the opposite transcriptional orientation. The neomycin cassette was excised through a cross with a Gt(ROSA)26Sor FLP strain on an unknown genetic background and the floxed exons were deleted through a cross with a Cre strain with a widespread pattern of expression on an unknown genetic background. Cre has been selectively bred away from the line. (J:169738)