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Tongzhong Ju

Tongzhong Ju

Emory University School of Medicine, USA

Title: Cellular O-glycome reporter/amplification to explore O-glycans of living cells

Biography

Tongzhong Ju received his M.D. degree from the Qingdao Medical College
in1986 and his Ph.D. in Biochemistry from Fudan University Shanghai
Medical School (former Shanghai Medical University, China) in 1994. He
completed his post-doctoral training in Biochemistry/Glycobiology in 1999, worked as a Research Associate (1999-2002) and Research Assistant
Professor (2002-2006) at the University of Oklahoma Health Sciences
Center (OUHSC). Since 2006, Dr. Ju has been an Assistant Professor, and now an Associate Professor in the Department of Biochemistry at Emory University School of Medicine. He has published more than 50 papers in many different reputable journals.

Abstract

Mucin–type O-glycosylation of Proteins is one of the most abundant protein post-translational modifications, and plays important roles in many biological processes, but the repertoire of mucin-type O-glycans synthesized by cells is difficult to determine. Here we developed a novel technology termed Cellular O-Glycome Reporter/Amplification (CORA), a sensitive and versatile method to profile and amplify mucin type O-glycans in any living cells. Cells took up peracetylated benzyl-α-N-acetylgalactosamine, Benzyl-α-GalNAc(Ac)3 into cytosol where it was de-acetylated to form Bn-α-GalNAc, and Benzyl-α-GalNAc was then transported into the Golgi apparatus where it was converted to a large variety of complex O-glycans (Benzyl-O-glycans) by O-glycosyltransferases; and these Benzyl-O-glycans were finally secreted from cells, allowing easy purification for analysis by HPLC and mass spectrometry (MS). CORA resulted in ~100-1000-fold increase in sensitivity over conventional O-glycan analyses, such as β-elimination-MS and identified a more complex repertoire of O-glycans in more than a dozen cell types analyzed. Thus, the high sensitivity and amplification nature of CORA technology makes it possible to analyze entire human O-glycome and others, and offers new opportunities to identify novel glycan biomarkers for human diseases. Furthermore, CORA technology may shed the light on facilitating the development of similar technologies for analyzing/amplifying other types of cellular glycomes.