Del(8Pcid2-Cul4a)1Ktc

A floxed region containing exon 1 and approximately 1.1 kb of upstream sequence was deleted by the expression of cre recombinase in vitro. Though sequence analysis showed the deletion to generate an in frame translational start codon at position 146, a truncated protein product was undetected by Western blot analysis of homozygous mutant mice. In a subsequent publication (J:150427), the authors demonstrate that that the upstream loxP site was inserted in a separate gene, Pcid2, that lies in a head-to-head configuration with Cul4a. This loxP site, inserted in a NotI restriction site, lies downstream of the putative translational start site of the gene. Thus the cre-mediated excision potentially disrupted both genes. RNAi knockdown of the Pcid2 transcript in ES cells suggests the embryonic lethality associated with this allele is at least partially due to disruption of the Pcid2 gene. (J:78032, J:150427)