Highly selective in vivo labeling of subcutaneous white adipocyte precursors with Prx1-Cre

Abstract

The origins of individual fat depots are not well understood, and thus, the availability of tools useful for studying depot-specific adipose tissue development and function is limited. Cre drivers that selectively target only brown adipocyte, subcutaneous white adipocyte, or visceral white adipocyte precursors would have significant value because they could be used to selectively study individual depots without impacting the adipocyte precursors or intrinsic metabolic properties of the other depots. Here, we show that the majority of the precursor and mature subcutaneous white adipocytes in adult C57Bl/6 mice are labeled by Prx1-Cre. In sharp contrast, few to no brown adipocytes or visceral white adipocytes are marked by Prx1-Cre. This suggests that Prx1-Cre-mediated recombination may be useful for making depot-restricted genetic manipulations in subcutaneous white adipocyte precursor cells, particularly when targeting genes with fat-specific functions.

Graphical abstract

Figure 1

Prx1-Cre Labels Adipocyte Precursors in Subcutaneous White Fats (A) SVF populations analyzed in the present study by flow. (B–G) Number of tdTomato⁺ and mGFP⁺ APCs isolated from each of the indicated depots from 6-week-old Prx1-cre;R26R-mTmG males and females (n = 3 per each sex; mean + SEM). See also Figure S1.

Figure 2

Prx1-Cre Labels Mature Subcutaneous White Adipocytes (A–F) Representative images of the indicated WATs of 6-week-old Prx1-Cre;R26R-mTmG male and female mice (top insert, tdTomato; bottom insert, mGFP). The number of tdTomato⁺ and mGFP⁺ mature white adipocytes in each depot is indicated in a graph at the left side of each row (n = 3 per each sex; mean + SEM). For all panels, scale bar represents 50 μm. See also Figure S2.

Figure 3

Most Brown Adipocytes Are Not Labeled by Prx1-Cre (A–E) Representative images of the indicated BATs of 6-week-old Prx1-Cre;R26R-mTmG male and female mice (top insert, tdTomato; bottom insert, mGFP). The number of tdTomato⁺ and mGFP⁺ mature brown adipocytes in each depot is indicated in a graph at the left side of each row (n = 3 per each sex; mean + SEM). For all panels, scale bar represents 50 μm. See also Figure S2.

Figure 4

Prx1-Cre Targeting Shows a High Degree of Selectivity to Subcutaneous WAT (A) mGFP mRNA expression in the indicated tissues. Dotted line indicates the background level of mGFP expression (defined as the level of expression of mGFP in no-Cre mice; n = 3 mice; mean + SEM). (B) Representative images of the indicated skeletal muscles from Prx1-cre;R26R-mTmG mice. For all panels, scale bar represents 50 μm. (C) Representative images of the indicated WATs of 6-week-old Prx1-Cre;R26R-mTmG male mice treated with CL316,243 for 1 week (top insert, tdTomato; bottom insert, mGFP; n = 3 mice; mean + SEM). For all panels, scale bar represents 50 μm. See also Figures S3 and S4.