A microRNA cluster controls fat cell differentiation and adipose tissue expansion by regulating SNCG

We present here lipidomic data from subcutaneous adipose tissue from 20 miR-KO mice and Wt controls under normal chow (1:1, male/females) (5 animals/experimental condition). Prior to lipid extraction, fat samples were spiked with internal standards and solvent of standards was removed by vacuum centrifugation. Then, samples were homogenized with a Precellys® 24 tissue homogenizer (Bertin Instruments). Homogenates containing a wet weight of 2 mg were extracted according to the protocol described by Bligh and Dyer. The analysis of lipids was performed by direct flow injection analysis (FIA), using either a triple quadrupole mass spectrometer (QQQ; FIA-MS/MS) or a hybrid quadrupole-Orbitrap high-resolution mass spectrometer (FIA-FTMS). Both instruments were equipped with a heated electrospray ionization source. FIA-MS/MS (QQQ) was performed in positive ion mode. The following neutral losses were applied: PE, 141 and PI, 277. PE-based plasmalogens (PE P) were analyzed according to the principles described by Berry and colleagues. Sphingosine-based Cer were analyzed using a fragment ion of m/z 264. Correction for isotopic overlap of lipid species was performed for all lipid classes. TG and DG were recorded in positive ion mode as [M+NH4]+ in m/z range 500–1000 and a target resolution of 140,000 (at m/z 200). PC and SM were analyzed as [M+HCOO]- in negative ion mode in m/z range 520–960 at the same resolution setting. Peak assignment was performed with the ALEX software and applied a mass accuracy of less than 3 ppm. Quantification was achieved by multiplication of the spiked-in IS amount with the analyte-to-IS intensity ratio. The following lipid species were applied as internal standards: Cer 18:1;O2/14:0, Cer 18:1;O2/17:0, DG 14:0/14:0/0:0, DG 20:0/20:0/0:0, HexCer 18:1;O2/12:0, HexCer 18:1;O2/17:0, LPC 13:0/0:0, LPC 19:0/0:0, PC 14:0/14:0, PC 22:0/22:0, PE 14:0/14:0, PE 20:0/20:0, PI 17:0/17:0, SM 18:1;O2/12:0, TG 17:0/17:0/17:0, and TG 19:0/19:0/19:0. Extracted data were processed by self-programmed Macros.