Differential expression of miRNAs in CD31+ vascular fragments isolated from mature mouse organs. Anti-CD31-coated magnetic beads were used to isolate microvascular fragments from adult (8 weeks) C57Bl/6 mouse organs. cDNA was prepared from the fragments and the remaining tissue using equal amounts of RNA, and miR-145 expression levels were determined using TaqMan qRT-PCR. The figure shows average paired expression ratios between fragments and surrounding tissue ± standard error of the mean (n = 4, 3, 2 and 4 for brain, muscle, skin and kidney, respectively). GAPDH, CD31 and VEGFR-2 (Flk1) TaqMan assays were used as quality controls.