Professor Mark Christian is a theme lead in Diabetes, Chronic Diseases and Aging. The Christian laboratory is focused on determining the mechanisms that regulate gene expression in development and metabolism with research programmes on the study of brown adipocyte biology and the role of lipid droplets in stem cells.
Prof Christian was a lecturer at Imperial College London before being appointed as an Associate Professor at the University of Warwick. With funding from the BBSRC and European Union FP7 he has given new understanding to the key differences between brown and white adipose tissue as well as the mechanisms of lipid droplet enlargement. As a Post Doc researcher at Imperial College London his work in reproductive biology determined key steroid hormone-controlled molecular events that prepare the endometrium for implantation. He continued his research on steroid hormone action at the level of co-modulator interaction and determined actions of the co-repressor RIP140 in adipose tissue metabolism. He was appointed as a lecturer at Imperial College London and developed his research programme on brown adipocyte biology and the action of genes enriched in this tissue including the lipid-droplet-associated protein CIDEA. Following his appointment at the University of Warwick he investigated the role of G protein coupled receptors in brown adipocyte biology and expanded the study of CIDEA action to stem cell biology and continues these studies at Nottingham Trent University.
The Christian laboratory is characterising cells of the anatomically distinct white and brown adipose tissue depots and defining the action of hormones, dietary stimuli and inflammation on adipocyte biology. Brown adipose tissue is an important target for combatting obesity as it serves to dissipate energy as heat. The aim is to determine the actions of key factors that control the fundamental processes essential for the unique functions of brown adipocytes.
Prof Christian is investigating the roles that microRNAs play in determining the key differences between brown and white adipocytes and the mechanism of their secretion and systemic effects on other tissues. MicroRNAs are small non coding RNAs that are important regulators of gene expression and essential for cell differentiation. They can be secreted through incorporation into vesicles and their presence in several body fluids suggests involvement in cell to cell communication.
The study of factors that regulate lipid storage in different tissues is essential for understanding and controlling metabolic disorders. Cellular lipid storage is determined by a group of proteins that coat lipid droplets and facilitate storage or utilisation by regulation of metabolic processes. Prof Christian has defined the molecular mechanism of the brown fat protein CIDEA in lipid droplet enlargement through binding of phosphatidic acid. By studying the function and regulation of CIDEA, he is determining the impact of this protein on lipid storage in different cellular systems. Importantly, he is presently investigating the role CIDEA and lipid droplet dynamics in the biology of embryonic stem cells.