Ava Conyer
MIT Department: Biological Engineering
Faculty Mentor: Prof. Anders Hansen
Research Supervisor: Sumin Kim
Undergraduate Institution: Howard University
Hometown: Burlington, New Jersey
Website: LinkedIn
Biography
Ava Conyer is a dedicated Chemical Engineering student at Howard University, focused on scientific research and innovation. As an MSRP summer intern, she worked in Dr. Anders Hansen’s lab, studying the role of polycomb bodies in developmental gene repression. Ava’s research experience spans studying bottlebrush polymers at Stanford University and DNA polymerase theta at MD Anderson Cancer Center, highlighting her strong passion for understanding complex biological processes and their health implications. Her proactive learning approach and adaptability have made her a valued research team member. Beyond academics, Ava is the Co-Editor-In-Chief of the Howard University Undergraduate Research Journal, demonstrating her commitment to academic excellence and communication. She also mentors young girls in Washington, D.C., showcasing her dedication to empowering the next generation. Ava’s dedication to her field and desire to contribute to scientific advancements underscore her potential as a future leader in research and innovation.
Abstract
Microscopy Analysis of Polycomb-Mediated 3-Dimensional Interactions
Ava C. Conyer1, Sumin Kim2, and Anders Hansen2
1Department of Chemical Engineering, Howard University
2Department of Biological Engineering, Massachusetts Institute of Technology
Gene expression is a tightly-regulated process that is essential to cellular function and development. The Polycomb repressive system silences lineage-specific developmental genes to maintain pluripotency of stem cells, ensuring that aberrant cellular differentiation does not result in abnormal cell fates. Despite their importance, how Polycomb establishes repression of its target genes, including whether repression is established every cell cycle and its dynamics and 3D organization, remain poorly understood.
The Polycomb repressive system consists of two chromatin regulatory complexes, PRC1 and PRC2, which are each composed of Polycomb group proteins. PRC1 and PRC2 catalyze repressive histone modifications and mediate 3D organization of the genome. Polycomb group proteins form nuclear structures called Polycomb bodies. Despite their striking appearance as bright foci, how Polycomb bodies relate to Polycomb function is unclear. Using mouse embryonic stem cells (mESCs) and live-cell imaging, we asked whether Polycomb bodies represent regions enriched for Polycomb-mediated 3D interactions by comparing the growth condition in which strong Polycomb binding and genomic interactions are visible to another in which Polycomb binds weakly. We found that Polycomb bodies are largely absent in mESCs without strong Polycomb binding and 3D interactions, suggesting that Polycomb bodies represent regions within the nucleus where Polycomb proteins bind to target genes and mediate genomic interactions. We next asked whether Polycomb bodies dissolve and re-establish every cell cycle, and observed disappearance of Polycomb bodies coinciding with chromosome condensation prior to nuclear envelope breakdown. Together, our findings suggest that Polycomb bodies represent sites of Polycomb-mediated 3D interactions, and that these interactions are re-established following mitosis. Studying these dynamics can help advance our understanding of Polycomb function and its crucial role in regulating gene expression and cellular development.
