The long non-coding RNAs (lncRNAs) are an emerging and rapidly-growing class of functional genomic elements, and a number have been shown to regulate fundamental biological processes, but the scope of their influence in metabolic disorders remains unknown. Identifying and characterizing metabolically-relevant lncRNAs will be crucial to obtaining a better understanding the pathophysiology of obesity and other diseases of metabolism. The candidate aspires to contribute to this understanding by studying novel metabolic regulators, while developing additional experience in relevant research techniques and receiving the necessary career development training to transition to a role as an independent principal investigator. Expanding on the candidate?s recent genome-wide screen that identified 140 lncRNAs and 239 mRNAs sensitive to metabolic conditions in mouse liver, the proposed research will study the roles of one novel lncRNA, Gm15441, in regulating triglyceride (TG) and cholesterol metabolism (Aim 1) and one novel protein-coding gene, Rab30, in regulating autophagy, free fatty acid (FFA) oxidation, and TG secretion in mouse livers (Aim 2). The mechanism by which Gm15441 regulates TG and cholesterol metabolism will be defined by exploring its cis-regulation of the overlapping metabolically-relevant protein-coding gene. In preliminary experiments, knockdown of Rab30 affected autophagy and lipid metabolism in fasting mouse livers, therefore the role of Rab30 in membrane trafficking will be determined. Additionally, the comprehensive bioinformatics analysis pipeline established in the recent genome-wide screen will be applied to human liver samples, to identify novel lncRNA metabolic regulators in human liver (Aim 3). The efficacy of this pipeline for predicting the function of human genes was established in preliminary experiments by testing known metabolic genes, such as G6PC (glucose-6-phosphatase catalytic subunit), which was correctly predicted to function in gluconeogenesis. A K22 award will offer this candidate the opportunity to develop new skills in CRISPR, confocal microscopy, cell biology, and bioinformatics. The candidate will develop these skills while developing experience in pursuing research of translational significance. Gm15441, for instance, is localized in a region that is syntenic with the human 1q21-23 locus, implicated in type 2 diabetes mellitus and familial combined hyperlipidemia. The candidate has developed a comprehensive plan for the development of her career, has identified coursework that will confer necessary skills for success as an independent investigator, and has secured a team of distinguished mentors and advisors who will support her throughout her career transition. Successful completion of the work described in this proposal could provide critical insight into the regulatory networks of hepatic and systemic metabolism, and will afford the candidate the ability to achieve research independence.
Our current therapeutic options for obesity and obesity-related diseases such as diabetes, fatty liver disease, and cancer are very limited, partly due to the gaps in our understanding of metabolism and metabolic pathophysiology. The lncRNA and mRNA metabolic regulators in mouse and human liver characterized in this proposal will provide novel therapeutic targets for obesity and obesity-related diseases. !
