The nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPAR?) is a master regulator of adipogenesis and metabolism. The widely used anti-diabetic class of thiazolinedione (TZD) drugs target PPAR? to decrease circulating levels of glucose, insulin, triglycerides, and free fatty acids;however, te molecular mechanisms and cell targets of these actions are not completely understood. We have employed a novel genome-wide technique, Global Run-On Sequencing (GRO-seq) to identify TZD-induced long non- coding RNAs (lncRNA) from PPAR? bound enhancers, (eRNAs), in adipocytes. We hypothesize that eRNAs mediate PPAR? expression profiles in adipocytes and dictate cell-specific TZD-induced gene expression networks.
The first aim of this proposal is dedicated to determining the physiological significance and mechanism of action of eRNAs in adipocytes. Both global and individual functions of eRNAs will be tested in experiments using RNAse or eRNA knockdown and overexpression.
The second aim uses GRO-seq to identify eRNAs in macrophages. GRO-seq datasets of adipocytes and macrophages will be compared to identify cell type specific eRNAs. Identification of novel adipocyte specific factors and understanding their mechanism of action has the potential of tailoring therapeutics for cell specific actions to minimize adverse side-effects of TZDs.
Safety concerns have caused a decrease in the use of thiazolidinediones (TZD), which are the only available drugs that reverse the hallmark characteristic of type 2 diabetes, insulin resistance. The goal of the proposed research is to identify and determine the function of adipocyte specific eRNAs in order to tailor current anti-diabetic therapeutics for cell specific actions, thus minimizing adverse side-effects.