Figure 6.
BAT-expressed LDB1 regulates key thermogenic factors. BAT expression analysis of gluco- and lipo-regulatory genes and thermogenic genes in (a) Ldb1+/− (n = 10 to 14 mice/group) and (b) Ldb1Δβ-cell (n= 6 to 13 mice/group) compared with their respective control (CTL) littermates after HF feeding. BAT mRNA levels were normalized to Hprt or 36B4. (c) Immunohistochemical staining images for LDB1, PPARγ, and ISL1 in BAT from chow-fed CTL C57BL/6 mice. (d) Schematic of the mouse Elovl3 5′ sequence demonstrating several putative core homeodomain-binding elements that may associate with LDB1 complexes. (e) LDB1 ChIP using chromatin isolated from chow-fed CTL mouse BAT demonstrates LDB1 enrichment of Elovl3 5′ sequences containing a homeodomain binding element (site 3 in d; n = 4). (f) Representative Western-blot image of LDB1 and Elovl3 protein in BAT of chow-fed CTL and Ldb1+/− mice (n = 3 for each genotype). Actin is included as loading control. Protein markers (in kilodaltons) are shown. Data are represented as mean ± SEM. *P < 0.05; **P < 0.01; ****P < 0.0001. a.u., arbitrary units.