|New Progress for Cell Biology|
ZHU Xueliang, a research fellow at Laboratory of Molecular Cell Biology, CAS Shanghai Institutes for Biological Sciences, and ZHENG Yixian at Department of Embryology, Carnegie Institution for Science, have found through study that both Nudel and dynein have played an important role in the assembly of the lamin B spindle matrix, allowing a proper microtubule organization during spindle assembly. The finding was published in the February 9, 2008 online issue of Nature Cell Biology.
Researchers studied the changes in microtubule organization, and found that microtubules grew first from Aurora A, in a shape of aster, together with Lamin B particles on microtubules. The microtubules would grow larger in density but shorter in length over time into a spherical matter. The two asters would be further developed into spindles, with a high concentration of Lamin B particles. They also found that the isolated spindle matrix has contained both dynein and Nudel, and that Lamin B interacts directly with Nudel. However, disrupting the function of Nudel or dynein would result in disorganized spindle and spindle poles, indicating that dynein and Nudel regulate assembly of the lamin B matrix. Researchers suggest that more work needs to be done to understand the functions of spindle matrix, as the isolated spindle matrix has contained a range of important proteins for cell signal forwarding, regulation, and membrane shipping.
The study was funded by the Chinese Ministry of Science and Technology, National Natural Science Foundation, Chinese Academy of Sciences, Howard Hughes Medical Institute, and Carnegie Institution for Science.