TRADD Gene Targeting in Human DG75 B Lymphocytes

(A) Knockout strategy. Given base positions relate to the transcriptional start site at position +1. The complete TRADD open reading frame (black boxes, exons 2–5 with ATG at position +3218) was deleted by homologous recombination with pTRADDko.1 (first allele) and pTRADDko.2 (second allele). C, CMV promoter; P, promoter; SV, SV40 promoter; TK, thymidine kinase.

(B) Southern blot analysis of the resulting DG75 clones with EcoRI-digested chromosomal DNA and the external probe 1. The genealogy of clones is illustrated by arrows. WT, TRADD wild-type allele; KO, targeted and Cre-deleted alleles 1 or 2, respectively.

(C) TRADD protein expression. Immunoblot analysis using the mouse anti-TRADD antibody.