Topic： Molecular Insights into Immunoglobulins

Speaker： Prof. Junyu Xiao

Host： Prof. Maofu Liao

Time： May 28, 10:00 - 11:30 am

Venue： Lynn Library Lecture Hall 111

Abstract:

Immunoglobulins, or antibodies, play a crucial role in the immune system and are classified into five main classes—IgM, IgD, IgG, IgE, and IgA—based on differences in their heavy chains. Our research addresses key questions regarding these essential molecules. Through detailed structural analysis of human IgM, we have uncovered its asymmetric assembly mechanism, primarily driven by the carboxy-terminal tailpiece and the joining chain. We also investigated IgM's interactions with specific receptors, including pIgR and FcμR, as well as binding proteins like CD5L. Furthermore, our findings reveal significant similarities between the assembly mechanisms of IgA and IgM. Additionally, we have elucidated the molecular basis of high-affinity IgE receptor complexes and demonstrated that a cholesterol-like molecule enhances the interaction between FcεRIβ and the FcεRIα–FcRγ complex. These insights enhance our understanding of these vital immunoglobulins and pave the way for the development of innovative antibody therapies.

Introduction:

Junyu Xiao earned his Ph.D. from the University of Michigan in 2008 under the guidance of Dr. Zhaohui Xu at the Life Sciences Institute. From 2009 to 2013, he conducted postdoctoral research with Dr. Jack Dixon at the University of California San Diego. He set up his independent research group in Peking University in 2014. He is currently a professor position in the School of Life Sciences (SLS) at Peking University and also a Principal Investigator at the Peking-Tsinghua Center for Life Science (CLS).