Cell and genome organization in mitosis, development, and homeostasis

Wednesday, June 20, 2018 | 3:00 to 4:00 p.m. ET

Yixian Zheng, Ph.D.

Investigator

Carnegie Institution for Science

Website

Summary

I began my research career studying how microtubules regulate various cellular processes, especially microtubule assembly, mitotic spindle assembly, and chromosome segregation. As a Ph.D. student in Dr. Berl Oakley’s lab, my study of g-tubulin has inspired me to use biochemical approaches to investigate the mechanism of microtubule nucleation as a postdoctoral fellow in Drs. Bruce Alberts and Tim Mitchison’s labs at UCSF. This has led to the discovery of the g-tubulin ring complex (gTuRC) and the demonstration of its microtubule-nucleating activity from purified tubulins. After establishing my lab, we discovered the role of RanGTPase in regulating spindle assembly in mitosis. Our more recent study of the mitotic spindle matrix has led to the finding that the nuclear lamin-B is part of the spindle matrix. We show that lamin-B plays a role in mitotic spindle morphogenesis and spindle orientation. In recent years, our research has expanded into studying the role of lamins in the interphase nucleus. By analyzing lamin deletions in mice, mouse ES cells, and various Drosophila stem cells, we have shown that lamins play important roles in organogenesis during development. Additionally, we show that lamin-B prevents immunosenescence and system inflammation upon organismal aging by maintaining the heterochromatin in immune organs.