Protein profiling of 3T3-L1 adipocyte differentiation and (tumor necrosis factor ?-mediated) starvation

Maastricht Proteomics Center, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Department of Human Biology, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
Cellular and Molecular Life Sciences CMLS (Impact Factor: 5.81). 03/2005; 62(4):492-503. DOI: 10.1007/s00018-004-4498-9
Source: PubMed


The increased incidence of obesity and related disorders in Western societies requires a thorough understanding of the adipogenic process. Data at the protein level of this process are scarce. Therefore we performed a proteome analysis of differentiating and starving 3T3-L1 cells using two-dimensional gel electrophoresis combined with mass spectrometry. Effects of different starvation conditions were examined by subjecting 3T3-L1 adipocytes to caloric restriction, either in the absence or the presence of the lipolysis inducer tumor necrosis factor-alpha. Ninety-three differentially expressed proteins were found during differentiation and starvation of 3T3-L1 cells, 50 of which were identified. GenMAPP/MAPP-finder software revealed a non-reciprocal regulation of the glycolytic pathway during 3T3-L1 differentiation followed by starvation. Furthermore, proteins involved in growth regulation, cytoskeletal rearrangements and protein modification, 16 of which have not been described before in 3T3-L1 cells, were identified. In conclusion, our data provide valuable information for further understanding of the adipogenic process.

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    • "Two days after reaching confluence , preadipocytes were induced to differentiate into adipocytes by culturing in DMEM-F12 containing 10% FCS, 0.5 mM 3-isobutyl-1-methyl-xanthine, 1 lM dexamethasone and 10 lM prostaglandin I2 (Biomol, Plymouth Meeting, PA, USA) for 1 day, followed by 18 days in DMEM-F12 containing 10% FCS and 1 lM insulin (Sigma). Whole cell protein lysates were obtained from mouse 3T3-L1 cells before and 18 days following fat cell differentiation as previously described (Renes et al. 2005). The protein samples were processed for 2D protein gel electrophoresis and differentially expressed protein spots were subsequently analyzed by mass spectrometry as previously described (Bouwman et al. 2004). "
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