水木清华生命科学讲座系列

The packing of mammalian chromosome: a phase transition perspective

时间：2018-04-12 15:00-16:00

主讲人：高毅勤

主题：The packing of mammalian chromosome: a phase transition perspective

地点：清华大学医学科学楼B323

Introduction of speaker：高毅勤，北京大学化学与分子工程学院，北京大学生物动态光学成像中心研究员，国家杰出青年科学基金获得者。1993年本科毕业于四川大学化学系，1996年在中科院化学所获得硕士学位， 2001年获得加州理工学院博士学位，导师为Rudolph A. Marcus教授。2001年－2004年间在加州理工学院和哈佛大学做博士后研究（导师为Marcus和Martin Karplus教授）。2005年-2009年，美国得克萨斯农工大学化学系助理教授。2010-现今，北京大学化学与分子工程学院教授。他的研究领域是理论和计算化学。致力于发展理论与计算方法研究染色质结构和生物功能，生物分子的溶液构象，生物酶催化机制和化学反应中的溶剂化效应。曾获Pople Medal, 日本化学会Keynote Lecturer奖，美国Searle Scholar，Dreyfus新教授奖和Clauser Prize等。担任ACS Central Science, Chemistry of Materials, Journal of Chemical Physics，Interdisciplinary Sciences, 物理化学学报等期刊的编委。

Abstract:

The chromatin structure plays important roles in gene regulation. Several models have been proposed about the relationship between epigenetics as well as transcription factors and chromatin structure. However, our understanding of chromatin structure formation in different cell types and how chromatin 3D structures including TAD and compartment are determined or affected by the most fundamental feature, DNA sequences, are far from clear. We identified two types of genomic domains (called forests and prairies) based on the uneven sequential distribution of CGIs and found them to be genetically, epigenetically, transcriptionally, and structurally distinct. The specific interactions of the two domain types relate to cell-type specific gene regulation and cell-identity establishment. Meanwhile, they continue to spatially segregate from each other in development, differentiation and senescence at multiple scales. Furthermore, spatial separation of the two domains prompts us to propose a phase separation mechanism for chromatin structure formation. This mechanism allows us to discuss in a unified framework the chromatin structure formation in various biological events, including development, differentiation and senescence. In this talk, we will also discuss possible biological consequences emerging naturally from domain segregation and the phase separation mechanism including the temperature dependence of chromatin structures, and speculated that the variation in sequential mosaicity between species may relate to their important biological differences.