Constant crosstalk between epigenetic regulators and metabolism homeostasis ensures that several tissues can respond and adapt to environmental cues. Decreased levels of the lysine acetyltransferase (KAT), MOF, was recently associated with cerebral development and syndromic intellectual disability. However, the consequences of having a chronic reduction of MOF levels are still unveiled. Here we characterized by FIA-MS/MS the metabolic profile of Mof heterozygous animals. We generated the profile of 7 different organs that have distinct metabolic demands. Overall our analysis reveled that Mof heterozygous mice have impaired glucose homeostasis, fatty acids metabolism, and amino acid accumulation. Furthermore, when exposed ad libitum to high-fat diet those animals failed to gain fat mass, while the lean mass remains unalterable. Accordingly, at the molecular level, using the adipocyte model we found that Mof regulates the expression of PPARs and Slc2a4. In summary, we identified the first KAT that shows high-fat diet resistance and we propose that the chronic reduction of Mof has a strong impact on metabolic disorders.
Overall design: Experimental design: Visceral white adipocyte (WAT) from 2 control and 3 Mof +/- was extracted. WAT of 8 week old SD treated animals was minced and transferred into a Dounce homogenizer (loose pestle), covered with 1% formaldehyde in PBS, and dissociated, followed by 15 min incubation at room temperature (RT). During incubation, the tissue suspension was filtered using a nylon 70 µM cell strainer (Falcon, 352350). 125 mM glycine final was added to the sample, incubated at RT for 5 min and the suspension was pelleted for 5 min at 500 g. Cell pellets were washed twice in ice cold PBS and pelleted for 5 min at 500 g. For NEXON based nuclei isolation cell pellets were resuspended in 1ml of lysis buffer (10mM Tris-HCl pH 8, 10mM NaCl, 0.2% Igepal, protease inhibitor cocktail. Cell suspension was transferred into Covaris MilliTube (cat. No. 520130) and sonicated in Covaris instrument (E220) for 30 sec at peak power 75W, duty factor 10% and 200 cycles/burst. Nuclei were pelleted at 1000g at 20°C for 5min. Pellets were resuspended in 0.5% SDS and incubated at RT for 10min. Sample was diluted 1:5 in the digestion buffer (1.1% Triton, 1x CutSmart buffer , H2Odest). Up to 1*10^6 nuclei were digested with Cvik1 (5U/100.000 cells) at 25°C for 17hrs, shaking at 800rpm. Nuclei were pelleted for 5min at 1000g and washed in a nuclei wash solution (10mM Tris-HCl pH 8, 0.25% Triton, 0.2mg/ml BSA ) until residual fat was removed. Nuclei were pelleted at 5000g for 10min, resuspend in the shearing buffer (10mM Tris-HCl pH 8, 0.1% SDS, 1mM EDTA), transferred into Covaris MicroTube (cat. No. 520052) and sonicated for 6min at peak power 105W, duty factor 2% and 200 cycles/burst. Sample was diluted 1:6 in 1x iC1 buffer (iDeal ChIP-seq, Diagenode) and incubated with 2ug of antibody o/n at 4°C. The next day protein G Dynabeads were added and incubated for 3 hrs at 4°C. Beads were washed and DNA was eluted according to manufacturer's instructions (iDeal ChIP-seq, Diagenode). DNA was purified using MinElute PCR purification kit (Qiagen) for further analysis.
Less...