Our previous proteomics study revealed that long chain acyl CoA synthetase 1 (ACSL1) and gelsolin (GSN) are oppositely regulated in white adipose tissue of diet-induced obese rats. To firmly establish these proteins as mediators of adipogenic and/or lipogenic events, we efficiently knocked down the Acsl1 and Gsn genes using siRNA in 3T3-L1 adipocyte cells. Expectedly, Acsl1 knockdown stimulated expression of lipogenic genes. Interestingly, Gsn knockdown suppressed expression of lipogenic genes but strikingly increased that of Tnf alpha and Il6, which may have connections with lipolytic capacity of these genes. Conclusively, we provide clear evidence that ACSL1 and GSN are potential target proteins in the context of obesity. (C) 2012 Elsevier Inc. All rights reserved.