3D Molecules and a Baby

You are here



Dr. Yechun Xu, You-Yang and Dr. Minjun Li. Made at the Institute
When Yechun Xu held her newborn daughter You-Yang for the first time, she felt happy and hopeful, as do new mothers everywhere. Her husband Minjun Li, standing nearby, was happy too. The only thing missing was the chance to share their joy with the family members they had left behind in China, their homeland. The staff of the Kaplan Hospital in Rehovot did their best to make them feel at home; so did their friends and colleagues from the laboratory of Prof. Joel Sussman at the Weizmann Institute of Science, who went out of their way to play the role of extended family.

“I felt almost like a grandfather when You-Yang was born,” recalls Sussman, a member of Weizmann’s Structural Biology Department.

Sussman  first met Yechun at the Chinese Academy of Science’s Shanghai Institute of Materia Medica, where she was a doctoral student. Sussman and Weizmann colleague Prof. Israel Silman collaborated with Yechun’s Shanghai Institute mentors on a study of Huperzine A, an herb extract used in Chinese folk medicine. In July 2005, after Yechun obtained her Ph.D., the Israeli scientists invited her to conduct postdoctoral research at the Weizmann Institute. Working under the guidance of Sussman and Silman, she and colleagues solved the three-dimensional structure of different crystal forms of the enzyme BACE1, and of the complexes it forms with an inhibitor. BACE1 is involved in the formation of plaques in the brain that are characteristic of Alzheimer’s disease. As reported in their paper in Acta Crystallographica D Biological Crystallography, this study might help design future anti-Alzheimer drugs.

Meanwhile, Yechun’s husband, engineer Minjun Li (they had met when both were undergraduate students in chemistry at the East China Normal University in Shanghai) had also decided to study abroad. He quit his job with an international company specializing in magnetic resonance equipment and enrolled in a Ph.D. program at the University of Texas.
A detailed 3D structure of a new molecular probe (bottom), in complex with the binding site of the estrogen receptor, designed for detecting this receptor as part of an improved method for the diagnosis and treatment of breast cancer
But after a year in Houston, Minjun decided to move to Israel, where he could pursue his interest in biology while working side by side with his wife. That was how in the summer of 2006, when an interesting Ph.D. project was offered to him at Weizmann, Minjun joined his wife in Rehovot.

Minjun’s Ph.D. research – conducted under the joint guidance of Sussman and Prof. Hadassa Degani of the Biological Regulation Department – centered on a small molecule designed to target estrogen receptors. As the scientists reported in the Journal of Medicinal Chemistry, this molecule may in the future be used to treat breast cancer and other disorders in which estrogen receptors are overactive; it might also be used in the diagnosis of these diseases, serving as a biomarker for making certain abnormalities more easily visible in magnetic resonance imaging scans. The researchers crystallized the complex formed by the new molecule with the receptor’s binding site and solved its three-dimensional structure. “Knowing the structure may help design compounds with improved properties,” Minjun said in an interview before departing for Shanghai.
Plans for the Future
Summing up his stay at Weizmann, Minjun said he had greatly appreciated the way in which the Institute facilitates interdisciplinary research: “Weizmann has an open, informal atmosphere in which it’s very easy to communicate with people from other labs and departments.” He added that he found it especially useful to consult researchers involved in the compilation of Proteopedia (http://www.proteopedia.org), a collaborative 3D encyclopedia of proteins and other molecules developed at Weizmann by the Israel Structural Proteomics Center.

The time Minjun and Yechun spent at the Institute was also fruitful in areas outside of research: Yechun gave birth to You-Yang (known as Yo-Yo) in March of 2009. While Minjun stayed on to complete his Ph.D., Yechun and You-Yang moved back to China, so that Yechun could take up her new position at the Shanghai Institute of Materia Medica, as head of her own lab. Minjun followed at the end of 2011 after passing his Ph.D. exam. His plans for the future: to look for a research position, preferably in one of the international pharmaceutical companies that have recently been establishing research branches in China.

While Minjun and Yechun spent most their time on the Weizmann Institute campus enjoying the peaceful surroundings that allowed them to focus on research, they did tour Israel on weekends, visiting historic sites and geographical highlights – particularly the Dead Sea, a landmark all Chinese students learn about in high school. On one occasion, Minjun organized an informal seminar that brought several dozen Chinese students to Weizmann from other Israeli institutions of higher learning. Such gatherings are held by the Chinese student community in Israel about twice a year – usually at Weizmann – and like the previous seminars, this one focused on a variety of topics ranging from education, history and politics to practical matters.

The young Chinese couple praised the warm attitude of their research supervisors at Weizmann, who often invited them to their homes. “They were more like parents than bosses,” said Minjun.