Dido1^tm1Cmar

A targeting construct was designed to replace exon IV and most of exon III with a neomycin resistance cassette. Mutant cells lacked isoforms 1 and 2, but retained a short transcript for isoform 3. This transcript lacked exons III and IV, indicating that the original translation start signal was absent. The short protein had to be initiated at an ATG codon in exon V or a downstream codon. (J:101201)