SOX9 is part of a combinatorial marker that reveals early development and embryological origins of the mouse brown adipose tissue depots

Most brown adipocytes are located in structures called depots including the interscapular (iBAT), scapular (sBAT), and cervical (cBAT) depots. BAT depots arise from embryonic structures called somites, but their development is incompletely understood.

Here, scRNA-seq was applied to whole-trunk tissue from axial levels where the three major BAT depots are located in order to profile the transcriptome of brown adipocyte progenitors as well as other lineages derived from somites and lateral plate mesoderm. The range of timepoints was chosen to profile brown adipocyte progenitors from early lineage segregation, as observed by a combination of markers including Sox9 at E11.5, to E13.5 when depots are morphologically identifiable and brown pre-adipocyte markers are expressed.