Institute of Molecular Biology, Academia Sinica

郭惠思實驗室

Hui Si Kwok
https://www.kwokchromatinlab.org/

Research Field

Medicine

Introduction

I joined the Institute of Molecular Biology, Academia Sinica, as an Assistant Research Fellow in January 2026. I received my PhD from the National University of Singapore in the laboratory of Dr. Daniel Tenen, where I studied the roles of transcription factors and histone lysine acetyltransferases in hematopoiesis and acute myeloid leukemia. I then completed my postdoctoral training in the laboratories of Dr. Dieter Söll at Yale University and Dr. Brian Liau at Harvard University. During my postdoc, I developed and applied mutational approaches to investigate the functions of chromatin regulatory complexes in cancer.

My laboratory seeks to uncover how chromatin factors shape gene regulatory programs. Histones and chromatin regulators are central components of these process and are among the most frequently mutated proteins in cancer. Despite their importance, many of these proteins have diverse functions, yet the molecular mechanisms underlying their activities remain poorly understood. 

To address this challenge, we combine functional genomics, mutagenesis, and mechanistic studies to interrogate protein function at unprecedented scale and resolution. Using CRISPR-based endogenous mutagenesis and other genetic approaches, we systematically identify the protein regions and molecular interactions required for function. We integrate cellular, genomic, and biochemical approaches to uncover mechanisms by which chromatin regulators control gene expression and how their disruption contributes to disease. Our goal is to identify therapeutic vulnerabilities and translate these discoveries into new cancer therapies.

Chromatin regulators and histones constitute the fundamental machinery that governs access to the genome. Notably, genes encoding these factors are among the most frequently mutated in human cancer. A particular focus of our research is understanding how mutations in histone lysine methyltransferases and histones rewire chromatin regulation to drive tumorigenesis. More broadly, we seek to uncover the molecular mechanisms by which chromatin-associated factors regulate gene expression and how their disruption contributes to disease. By integrating functional genomics with mechanistic studies, we investigate how altered chromatin regulation gives rise to pathological states. We aim to connect genetic variation to molecular mechanisms and cellular phenotypes, thereby identifying actionable vulnerabilities that can be exploited for cancer treatment. 


Research Topics

Our approach:
We develop and apply protein-centric genetic approaches to systematically map the functional architecture of chromatin regulators. Using endogenous mutagenesis and complementary mechanistic approaches, we delineate how individual protein domains, residues, and molecular interactions regulate gene expression in normal physiology and disease.
 

Research themes
1. Illuminating NSD1 and NSD2 function through mutational analysis

NSD1 and NSD2 are H3K36 methyltransferases that are frequently altered in human cancers. These proteins are large and contain multiple functional domains, yet how these domains coordinate enzymatic activity and chromatin engagement remains poorly understood. We combine mutational scanning with genetic and biochemical approaches to systematically dissect the contributions of individual domains to protein function. By leveraging disease-associated mutations, we seek to uncover how NSD dysregulation drives cancer and identify potential therapeutic vulnerabilities. 

2. Uncovering linker histone H1 function in cancer

Histones are the fundamental structural components of chromatin around which the genome is organized. Linker histone H1 is a key regulator of chromatin compaction and gene repression. Notably, several H1 paralogs are frequently mutated in lymphoma. While the globular domain of H1 mediates nucleosome binding and chromatin compaction, many lymphoma-associated mutations occur outside this domain within poorly understood intrinsically disordered regions. We aim to determine how these disordered regions contribute to chromatin organization and gene regulation.  


Honor

2025     Forbeck Scholar Award

2023     Abstract Achievement Award, American Society of Hematology (ASH).

2023     Eliana Hechter Memorial Travel Prize, Broad Institute.

2022     Charles A. King Trust Postdoctoral Research Fellowship, Health Resources in Action.

2018     The Company of Biologists Travelling Fellowship.

2011      NUS Graduate School Scholarship, National University of Singapore.


Educational Background

2007-2010  B.Sc. in Biological Sciences (with First Class Honors), Nanyang Technological University, Singapore

2011-2016    Ph.D. in Cancer Biology, National University of Singapore, Singapore

2017-2019   Postdoctoral Fellow, Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA

2019-2025  Postdoctoral Fellow, Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA