Background: The cellular events that cause adipocytes to increase lipid capacity (hypertrophy) characteristic of obesity remain largely unknown. We have discovered that mice with targeted genetic deletion of diaphanous 1in adipose tissue are protected from diet-induced obesity and exhibit reliably elevated levels of the gene encoding the zinc finger protein 949 (Zfp949) in both brown and white adipose tissue. There is only limited published information regarding the physiological role of Zfp949 but what is available has identified Zfp949 as transcriptional suppressor of embryonic development. Preliminary data from our laboratory discovered that genetic manipulations that result in lowering the expression of Zfp949 in adipocytes causes those cells to accumulate significantly more triglycerides than control cells throughout the differentiation process. Thus, this novel model of adipocyte hypertrophy will allow us to identify the precise cellular changes that account for the increased lipid accumulation in Zfp949 knock-down adipocytes. Furthermore, the proposed studies aim to determine whether increasing the expression of Zfp949 represent a therapeutic target for the treatments and/or prevention of obesity. Hypothesis: In line with a common function of proteins in the zinc finger family and based on a published report supporting this role, we hypothesize that Zfp949 functions as suppressor of genes and proteins that promote lipid buildup in adipocytes. Furthermore, we hypothesize that adipocytes genetically altered to overexpressed Zfp949 will be protected from adipocyte hypertrophy and therefore it may represent a potential therapeutic target for the treatment and/or prevention of obesity and other diseases associated with excess lipid buildup. Approach: We will leverage RNA sequencing, proteomic and lipidomic studies to perform an unbiased assessment of the genes, proteins and lipid classes that underlie adipocyte hypertrophy and thereby gain insight into the cellular mechanisms that promote hypertrophy. Similarly, we will also harness those tools to assess whether or not overexpressing Zfp949 represents a potential therapeutic approach to treat obesity. Significance: One of the limitations to being able to study the cellular processes that take place in adipocytes during hypertrophy is that currently it is not technically feasible to isolate hypertrophied adipocytes from subjects in vivo to be able to identify the precise cellular changes that promote lipid accumulation. Here, we provide a new cellular model that will allow for detailed studies on the underlying cellular processes that promote adipocyte hypertrophy in vitro. Furthermore, in light of the lack of effective treatments for obesity, the fast growing prevalence of obesity and the fact that obesity is a risk factor for cardiovascular disease and diabetes, if is of paramount importance to be able to identify novel therapeutic targets for obesity. The clinical significance of the proposed...