Expression data from FACS sorted cell populations of immortalized stromovascular fraction mouse cells derived from inguinal white adipose tissue, showing either high or low binding to FcsFNDC4

Soluble FNDC4 (sFNDC4) is a novel hepatokine which promotes glucose tolerance in mice and positively associates with increased glucose tolerance in humans. To identify potential receptors for sFNDC4 we screened a population of immortalized stromovascular mouse cells derived from inguinal white fat for cells, which showed high (high binding cells-HBC) or low binding (low binding cells-LBC) to recombinant FcsFNDC4. We utilised microarray to identify differentially expressed genes between HBC and LBC. After comparing the global gene expression between HBC and LBC we were able to identify several differentially expressed genes encoding for cellular receptors. Experimental validations of these results and further experimental sutdies supported that GPR116 is the receptor for sFNDC4. Adherent immortalised SVF cells referenced in Duteil D. et al, PNAS 2017 were scraped and incubated for 40min at 4oC with FcsFNDC4 100nM, then wahsed twiced with 3%FBS (in PBS) at 4oC and incubated with secondary human IgG conjugated to PE (Phycoerythrin) for 40 min at 4oC. After two final washes, cells were checked for the levels of FcsFNDC4 bound protein by reading the levels of PE fluorescence with FACS.The fluorescence intesity was proportional to the amount of FcsFNDC4 bound to the cells. Cells which showed high amounts of FcsFNDC4 bound to them (HBC) or low amount of bound FcsFNDC4 (LBC) were sorted and plated in cell culure media. When cells reached 80% conlfuency, they were passaged to allow proliferation. The assay to test for FcsFNDC4 binding, as well as sorting on HBC and LBC via FACS was repeated for 20 times, when we finally had obtained HBC and LBC with consistently high and low levels of FcsFNDC4 binding.