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Jun Yin

Associate Professor

B.S. (1995): Peking University, Beijing, China
M.S. (1997): Rutgers University at New Brunswick
Ph.D. (2003): University of California at Berkeley
Postdoctoral Associate (2003-2006): Harvard Medical School
Assistant Professor (2006-2013): University of Chicago
Associate professor (2013-present): Georgia State University


Protein engineering, phage display, yeast cell surface display, proteomics, protein posttranslational modification, cell signaling.


Research Interest:

Protein modification by ubiquitin (UB) controls diverse cellular processes. UB is conjugated to cellular proteins by sequential transfer through an E1-E2-E3 enzymatic cascade. The cross-activities of 2 E1s, 50 E2s and hundreds of E3s encoded make it difficult to identify the cellular targets of a specific E3 to map it on a cell signaling network. To solve this problem, we used phage and yeast cell surface display to engineer orthogonal UB-E1, E1-E2 and E2-E3 pairs so that the engineered UB (xUB) can be exclusively used by a specific E3 to label its substarte proteins. We have constructed stable cell lines to express the engineered xE1-xE2-xE3 cascade for orthogonal UB transfer (OUT). We carried out tandem purification and proteomic profiling to identify the downstream targets of important E3s including E6AP, Rsp5, UBE4B, CHIP, Mdm2, Traf6, and BRCA1. We also study the mechanism of UB chain assembly by unnatural amino acid incorporation, structural biology, and enzyme mechanistic analysis.



Recent publications:
Bhuripanyo, K., Wang, Y., Liu, X., Zhou, L., Liu, R., Duong, D., Zhao, B., Bi, Y., Zhou, H., Chen, G., Seyfried, N. T., Chazin, W. J., Kiyokawa, H., and Yin, J. (2018) Identifying the substrate proteins of U-box E3s E4B and CHIP by orthogonal ubiquitin transfer, Sci Adv 4, e1701393. PubMed
Wang, Y., Liu, X., Zhou, L., Duong, D., Bhuripanyo, K., Zhao, B., Zhou, H., Liu, R., Bi, Y., Kiyokawa, H., and Yin, J. (2017) Identifying the ubiquitination targets of E6AP by orthogonal ubiquitin transfer, Nat Commun 8, 2232. Pubmed
Liu, X., Zhao, B., Sun, L., Bhuripanyo, K., Wang, Y., Bi, Y., Davuluri, R. V., Duong, D. M., Nanavati, D., Yin, J.*, and Kiyokawa, H.* (2017) Orthogonal ubiquitin transfer identifies ubiquitination substrates under differential control by the two ubiquitin activating enzymes, Nat Commun 8, 14286. *Corresponding authors. Pubmed
Zhao, B., Bhuripanyo, K., Zhang, K., Kiyokawa, H., Schindelin, H. & Yin, J. (2012). Orthogonal Ubiquitin Transfer through Engineered E1-E2 Cascade for Protein Ubiquitination. Chem Biol, 19, 1265-77. Pubmed