FIGURE 1. Conditional deletion of Mcl-1 results in loss of peripheral lymphocytes.

a, Schematic of Mcl-1 loci. PCR primers distinguishing these alleles include flox-forward (flox for) and flox-reverse (flox rev) primers that generate a 350-base-pair (bp) product in wt and null alleles, but a 400-bp product in flox alleles owing to the loxP site. The null primer set amplifies only the Mcl-1^null allele, whereas a combination of flox-for and null-rev primers amplifies selectively the Mcl-1^deleted() allele. UTR, untranslated region. b, Immunoblots of lysates from murine embryonic fibroblasts (MEFs). Mcl-1 cell lines were generated by transduction of tyrosine aminotransferase (Tat)–Cre fusion protein. c, Number of splenic T-cell subsets (mean s.e.m.) for three mice of Mcl-1^f/wt, Mcl-1^f/null, Lck–CreMcl-1^f/wt or Lck–CreMcl-1^f/null genotype at 8 weeks of age. d, Genomic DNA from sorted CD3⁺ splenic T cells was analysed by PCR to determine the representation of Mcl-1^wt, Mcl-1^flox, Mcl-1 and Mcl-1^null alleles. e, Number of splenic B220⁺ cells (mean s.e.m.) for three mice of Mcl-1^f/wt and Mcl-1^f/null with and without CD19–Cre^f/wt and CD19–Cre^f/null genotypes at 8 weeks of age. f, Genomic DNA from sorted B220⁺ splenic B cells was analysed by PCR to determine the representation of Mcl-1 alleles.