UROP Proceedings 2020-21

School of Science Division of Life Science 19 Understanding the Key Elements of Nucleosome/Chromatin Dynamics Supervisor: ISHIBASHI Toyotaka / LIFS Student: THEN Claudia Regina / SSCI Course: UROP1000, Summer The nucleosome is comprised of approximately 146 base pairs of DNA wrapped around a histone octamer, consisting of two copies of each core histone H2A, H2B, H3, and H4. Despite histones being highly conserved throughout evolution, several forms of histone variants have been found. In this study, we focused on four types of variant histones, namely H2BFM, H2AL2, TH2A, and TH2B. All of the variant histones mentioned are expressed in testes, however their functions remain unknown. To understand their functions, we made several plasmid constructs containing H2BFM, H2AL2, TH2A, and TH2B for expressing recombinant proteins with the Flag tag. These proteins can be used for chromatin immunoprecipitation assay to find the interaction partners in testes. Deciphering Epigenetic Changes in Cancer Supervisor: LEUNG Danny Chi Yeu / LIFS Student: KRISHNAMOORTHY Suhas / BIBU Course: UROP2100, Fall Epigenetics refers to the study of heritable changes in gene expression without alterations in DNA sequences. In cancer cells, genetic alterations are often preceded by or accompanied by alterations in the epigenetic makeup of the cell. Differential binding of transcription factors, histone modification marks and DNA methylation states have been observed in various types of cancer cells and could provide insight into the underlying mechanism of these cancers. Aberrant epigenetic patterns can potentially serve as powerful diagnostics tools such as classification markers, risk assessment markers and sensitive detection markers. In this project, differential analysis is done using ChIP seq data of the transcription factor CTCF as well as whole genome bisulfite sequencing data from A549 lung carcinoma cells. Regions which have differential enrichment for both CTCF binding and DNA methylation are then annotated to identify regions of interest. Bisulfite sequencing is then done at one of these regions to identify the DNA methylation pattern at base pair resolution. Deciphering Epigenetic Changes in Cancer Supervisor: LEUNG Danny Chi Yeu / LIFS Student: LEE Yeung / BCB Course: UROP1100, Summer Epigenetics focuses on the chemical modifications on DNA and histones which have significant contributions towards cell diversity through dynamic regulation of gene expression. Research in this area has profound significance uncovering mechanisms in molecular biology as well as clinical application such as in the investigation of glioblastoma multiforme. This paper briefly summarizes the basic molecular biology techniques essential to epigenomic research.