Knockdown expression and hepatic deficiency reveal an atheroprotective role for SR-BI in liver and peripheral tissues
J. Clin. Invest. Thierry Huby, et al. 116:2767 doi:10.1172/JCI26893 [Go to this article.]

Figure 1
Targeting strategy and conditional deletion of the SR-BI^flox allele. (A) Structural organization of the 5′ region of the wild-type, floxed, and knockout SR-BI allele. The 2 loxP sites flanking the SR-BI exon 1 are shown as arrowheads. The relative positions of probe A used for Southern blot analysis, primers (short arrows) used for PCR screening, and endonuclease sites for BamHI and XbaI are indicated. XbaI-restricted fragments for each allele are depicted by double-headed arrows. Cre-mediated deletion of the SR-BI^flox allele to generate the SR-BI–KO allele was achieved by transfection of the Cre recombinase cDNA in SR-BI^flox/+ ES cells. SR-BI^+/– ES cells were then used to generate SR-BI–KO mice. Mice with hepatic SR-BI deficiency were generated by interbreeding of SR-BI^flox/flox mice with Alb-Cre mice, which express the Cre recombinase in hepatocytes. (B) Southern blot analysis of XbaI-digested ES cell genomic DNA using probe A. (C) PCR analysis of tail and liver genomic DNA using a mix of SRBI.f4, SRBI.r4, and SRBI.r5 primers. Primer pair SRBI.f4 and SRBI.r4 discriminates for the presence or absence of the 5′-loxP sequence upstream SR-BI exon 1. The sizes of the PCR products for the WT and SR-BI floxed alleles are 391 bp and 427 bp, respectively. Primer pair SRBI.f4 and SRBI.r5 identifies the SR-BI–KO allele (288 bp).