선정자 소개
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KAIST
A set of recent evidences indicates that the accurate spatial organization of chromatin in a cell nucleus is crucial to the intricate gene expression pattern. Far from random, chromatin organization follows certain principles for its hierarchical architecture.
Recently developed genome-wide chromatin conformation capture and chromatin immunoprecipitation sequencing techniques have shown that the ordered chromatin structures reflect the necessity of connecting physically distant functional regions for gene activation. From previous studies, it is revealed that demanded transcription factors are highly accumulated at chromatin contacting loci and epigenetic markers for active genes are corresponding to the contacting regions as well. One remarkable aspect of chromatin organization is that the structure of chromatin is rapidly changed in response to external cues for maintaining homeostasis or proper cell differentiation, rather than keeping its static state. However, those results are from ensemble data by sequencing methods. Although sequencing techniques provide genome-wide information, they rely on sheared DNA fragments from millions of fixed cells, and most of them cannot reflect cell-to-cell heterogeneity; therefore, sequencing techniques cannot explain detailed mechanisms of dynamic changes of chromatin structure and their cooperativity with nuclear gene-regulatory components (such as transcription factors, non-coding RNAs, chromatin architectural proteins) in a living cell nucleus.
Thus, we propose a study to uncover real-time mechanisms of gene expression regulation due to the chromatin dynamics and their interactions with gene regulatory components, using up-to-date fluorescence microscopy in a single-cell level.
We established several steps aiming to achieve the goal. (1) First, we will set up a multi-color real-time visualization system using super-resolution fluorescence microscopy, developing a multi-chromatin loci labeling technique, which allows us to visualize chromatin movements, gene expression levels and transcription factor association at the same time in a living cell nucleus. (2) Second, we will clarify the correlation between chromatin dynamics and gene expression via quantifying physical distances of contacting chromatin loci and transcription outputs. (3) Third, we will examine the acting mechanism of essential nuclear gene-regulatory components for the chromatin dynamics. (4) Finally, we will investigate the disease models generated by chromatin disruption manipulated by mutating architectural proteins and nuclear lamina proteins.
This study is expected to elucidate the fundamental processes in gene regulation, which is controlled by chromatin dynamics in living nuclei.
세포핵 내에서 일어나는 전사 과정에 대한 이해는 서로 다른 종류의 세포나 질병 세포에서 보이는 상이한 유전자 발현 양상을 이해하기 위한 첫 단계이다. 최근 보급된 차세대 염기서열분석 기술은 그동안 전사인자들 간의 분자적 메커니즘으로만 이해해오던 전사 조절 과정에 유전자가 놓여있는 염색질의 구조나 인, 핵막과 같은 세포핵 내 구조체들도 결정적인 역할을 한다는 관점을 더해주었다. 하지만 현재까지 염기서열분석에 의한 이들 구조체들과 유전자들 간의 상호작용에 대한 연구는 고형화된 세포들로부터 수집된 DNA 조각들의 통계적인 결과라는 점에서 포괄적인 전사 조절 과정에 대한 이해에는 한계가 있었다. 본 연구는 살아있는 단일 세포핵 내에서 초고해상도 이미징을 통해 시시각각으로 변화하는 염색질의 단위체들과 핵 내 구조체들의 4차원 상호작용을 실시간으로 관찰하여 오랜 생물학 연구의 숙제인 전사 조절 과정에 대한 우리의 이해 증진에 기여하고자 한다.
- 연구분야
- 분자세포생물학
4-dimensional gene expression regulation by real-time single-cell imaging
Recently developed genome-wide chromatin conformation capture and chromatin immunoprecipitation sequencing techniques have shown that the ordered chromatin structures reflect the necessity of connecting physically distant functional regions for gene activation. From previous studies, it is revealed that demanded transcription factors are highly accumulated at chromatin contacting loci and epigenetic markers for active genes are corresponding to the contacting regions as well. One remarkable aspect of chromatin organization is that the structure of chromatin is rapidly changed in response to external cues for maintaining homeostasis or proper cell differentiation, rather than keeping its static state. However, those results are from ensemble data by sequencing methods. Although sequencing techniques provide genome-wide information, they rely on sheared DNA fragments from millions of fixed cells, and most of them cannot reflect cell-to-cell heterogeneity; therefore, sequencing techniques cannot explain detailed mechanisms of dynamic changes of chromatin structure and their cooperativity with nuclear gene-regulatory components (such as transcription factors, non-coding RNAs, chromatin architectural proteins) in a living cell nucleus.
Thus, we propose a study to uncover real-time mechanisms of gene expression regulation due to the chromatin dynamics and their interactions with gene regulatory components, using up-to-date fluorescence microscopy in a single-cell level.
We established several steps aiming to achieve the goal. (1) First, we will set up a multi-color real-time visualization system using super-resolution fluorescence microscopy, developing a multi-chromatin loci labeling technique, which allows us to visualize chromatin movements, gene expression levels and transcription factor association at the same time in a living cell nucleus. (2) Second, we will clarify the correlation between chromatin dynamics and gene expression via quantifying physical distances of contacting chromatin loci and transcription outputs. (3) Third, we will examine the acting mechanism of essential nuclear gene-regulatory components for the chromatin dynamics. (4) Finally, we will investigate the disease models generated by chromatin disruption manipulated by mutating architectural proteins and nuclear lamina proteins.
This study is expected to elucidate the fundamental processes in gene regulation, which is controlled by chromatin dynamics in living nuclei.
세포핵 내에서 일어나는 전사 과정에 대한 이해는 서로 다른 종류의 세포나 질병 세포에서 보이는 상이한 유전자 발현 양상을 이해하기 위한 첫 단계이다. 최근 보급된 차세대 염기서열분석 기술은 그동안 전사인자들 간의 분자적 메커니즘으로만 이해해오던 전사 조절 과정에 유전자가 놓여있는 염색질의 구조나 인, 핵막과 같은 세포핵 내 구조체들도 결정적인 역할을 한다는 관점을 더해주었다. 하지만 현재까지 염기서열분석에 의한 이들 구조체들과 유전자들 간의 상호작용에 대한 연구는 고형화된 세포들로부터 수집된 DNA 조각들의 통계적인 결과라는 점에서 포괄적인 전사 조절 과정에 대한 이해에는 한계가 있었다. 본 연구는 살아있는 단일 세포핵 내에서 초고해상도 이미징을 통해 시시각각으로 변화하는 염색질의 단위체들과 핵 내 구조체들의 4차원 상호작용을 실시간으로 관찰하여 오랜 생물학 연구의 숙제인 전사 조절 과정에 대한 우리의 이해 증진에 기여하고자 한다.
빛을 통해 세포라는 작은 우주를 탐험하여, 서경배재단의 정신에 부합하는 인류 삶의 질 향상에 이바지하는 연구를 해내겠습니다.
