Dr. Peng Yi grew up in Shandong, China. He graduated from the University of Science and Technology of China in 2003 with a B.S. degree in Molecular and Cell Biology. He then joined Professor Eric Olson's laboratory at the University of Texas, Southwestern Medical Center and obtained a Ph.D. degree in Genetics and Developmental Biology in 2007. In 2008, he moved to Boston and completed postdoctoral training in the laboratory of Professor Douglas Melton at Harvard University. He received the Helen Hays Whitney Foundation Postdoctoral Fellowship in 2009. During his postdoc training, he focused on pancreatic beta-cell replication and expansion. In 2013, Dr. Yi became an Assistant Investigator at the Joslin Diabetes Center.
The laboratory set up a new acute insulin resistance mouse model by infusion of an insulin receptor antagonist, S961, which induces dramatic and specific pancreatic beta-cell replication. Our major focus is using this model to search for novel secreted proteins and hormones from various organs/tissues, as well as beta-cell genes that control pancreatic beta-cell proliferation. We also use this model to study cross-organ communication that regulates beta cell functions.
The laboratory is also investigating the mechanism controlling the human beta-cell proliferation, regeneration and beta-cell tolerance to autoimmune attack. Using whole-genome gain-of-function and loss-of-function in vitro and in vivo screens, Dr. Yi's laboratory aims to identify positive and negative regulators for human beta-cell replication and beta-cell autoimmune tolerance, which will provide novel drug candidates and treatment targets for type 1 diabetes and late-stage type 2 diabetes.
Part of the effort is to characterize a newly discovered liver/fat secreted protein, Angptl8 (also known as RIFL, Lipasin, and Betatrophin). Despite the current controversy of this gene's function on beta-cell function, we found that Angptl8 acutely regulates glucose homeostasis and insulin secretion in mice. Using proteomics, biochemical and genetic approaches, Dr. Yi's laboratory is investigating the mechanism of Angptl8 regulated glucose homeostasis and searching for receptors of Angptl8.