Chinese scholars have found that the condensed matter of biological macromolecules can regulate the plasticity of spindle microtubules

Figure Schematic diagram of EB1 protein phase separation regulating cell division spindle microtubule plasticity

With the support of the National Natural Science Foundation of China (grant numbers: 32090040, 91854203, 31621002, 21922706), Yao Xuebiao's research group and collaborators of the University of Science and Technology of China carried out research to clarify the physicochemical mechanism of phase separation of end-binding protein (EB1 protein) to regulate the plasticity of spindle microtubules in cell division.
It has taken an important step in
the field of analyzing the plasticity of cell fate regulated by biomacromolecular condensates.
The related research results, titled "Phase separation of EB1 guides microtubule plus-end dynamics", were published in the journal Nature Cell Biology on December 19
, 2022.
Link to the paper: _istranslated="1">.

Cells are the smallest functional units of life activities, and biological macromolecules precisely catalyze biochemical reactions and regulate cell homeostasis and proliferation
by constructing compartments with different morphologies and functions.
The cytoskeleton is the material basis of its compartmentalization, regulating cell growth, morphological changes, intercellular information exchange and fate determination plasticity
.
In 2009, Yao Xuebiao's group discovered and cloned a novel EB1-binding protein TIP150
.
TIP150 contains the typical EB1-binding protein motif SxIP, responsible for recruiting the microtubule depolymerase MCAK, which forms catalytic compartments
at the positive end of the dynamically assembled microtubule.
On this basis, the research group collaborated with other researchers to analyze the dynamic mechanism and chemical basis
of EB1 and TIP150 by using single-molecule technologies TIRFM and FRET.

In order to further clarify the phase separation characteristics and condensed matter basis of EB1 protein, our research group cooperated with Professor Liu Xing of University of Science and Technology of China to discover the droplet characterization of EB1 protein in the dynamic microtubule tracking process of living cells by using structured light obvious microimaging technology, and then used gene editing, physicochemistry to simulate the abundance and spacing of basic amino acids, and combined with ultra-high-resolution imaging, to analyze the positive end tracking function
of phase separation driving EB1 protein.
The results of this study laid a foundation for the subsequent research on the regulation of cell division quality control and fate determination plasticity of biomacromolecular condensed matter (Figure).

The results were developed by cross-cutting teams of single-molecule tracking, physicochemical modeling, nuclear magnetic spectroscopy, and cell dynamics
.
Professor Jiang Kai of Wuhan University, Professor Li Dong of Institute of Biophysics, Chinese Academy of Sciences, Professor Li Lin of the Center for Excellence in Molecular Cells, Chinese Academy of Sciences, Professor Yuan Kai of Hunan University, Professor Li Pilong of Tsinghua University, Professor Xiang Shengqi, Professor Xu Chao, Professor Fu Chuanzi, Professor Zang Jianye, Professor Hou Zhonghuai and Professor Shi Yunyu of University of Science and Technology of China participated in the research
.