Fig. 1.
Identification of a Crkl mutation in snoopy mice. A Location of snoopy mutation (arrow) relative to Crkl coding sequence. B Whole-mount in situ hybridisation for the Crkl gene in wild-type, heterozygous and homozygous mutant embryos. C Relative quantitation of Crkl transcripts in snoopy embryos (* p = 0.0115, ** p = 0.0007). D Stabilisation of Crklsno transcript by cycloheximide. Cycloheximide treatment of embryonic fibroblasts results in stabilisation of the mutant RNA (arrowhead) which migrates more slowly than the wild-type transcript (arrow). EEF (eukaryotic translation elongation factor) was used as a loading control. E Sequencing the cycloheximide-stabilised mutant transcript revealed inclusion of 51 nucleotides of the Crkl intron. F Western blot analysis of protein extracted from whole E13.5 embryos demonstrated the loss of Crkl protein in mutants.