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<p>Abstract</p> <p>Background</p> <p>White adipose tissue is not only an energy storage organ; it also functions as an endocrine organ. The coordination and integration of numerous gene expression events is required to establish and maintain the adipocyte phenotype.</p> <p>Findings</p> <p>We previously observed a 45-fold upregulation for a transcript encoding a novel predicted transmembrane protein, Tmem182, upon brown preadipocyte to adipocyte conversion. Here we use real-time PCR analysis to further characterize Tmem182 transcript expression in the adipocyte lineage. Analysis across a panel of 10 murine tissues revealed highest Tmem182 transcript expression in white adipose tissues (WAT), with 10-fold to 20-fold higher levels than in brown adipose tissue (BAT). Tmem182 transcript expression is ~3-fold upregulated in BAT of genetically obese (<it>ob/ob</it>) mice <it>vs. </it>wild type C57BL/6. Analysis of three <it>in vitro </it>models of white adipogenesis indicates markedly enriched expression of Tmem182 transcript in adipocytes <it>vs. </it>preadipocytes. Compared to 3T3-L1 preadipocytes, a 157-fold higher level of Tmem182 transcript is detected at 3 day post-induction of adipogenesis and an ~2500-fold higher level in mature 3T3-L1 adipocytes. TNFα treatment of 3T3-L1 adipocytes resulted in a ~90% decrease in Tmem182 transcript level. As skeletal muscle and heart were also found to express Tmem182 transcript, we assessed expression in C2C12 myogenesis and observed a ~770-fold upregulation upon conversion of myoblasts to myocytes.</p> <p>Conclusion</p> <p>WAT is the most prominent site of Tmem182 transcript expression and levels of transcript for Tmem182 are altered in adipose tissues of <it>ob/ob </it>mice and upon exposure of 3T3-L1 adipocytes to the proinflammatory cytokine TNFα. The dramatic upregulation of Tmem182 transcript during <it>in vitro </it>adipogenesis and myogenesis suggests Tmem182 may function in intracellular pathways important in these two cell types.</p>