Coral Y Zhou

Genome size (the number of base pairs of DNA) varies by six orders of magnitude across the tree of life but we do not know how the extensive molecular machinery that packages, transcribes, and repairs the genome has evolved along with these major changes in size. Additionally, genomes are themselves physical entities, with specific size and shape constraints that must also fit and function within the constraints of the highly dynamic cell.

Within this context, my laboratory asks: How do genomes adapt to major changes in size? We aim to dissect the molecular mechanisms of genome size control across the cell cycle, during early development and across evolution. We primarily utilize the African clawed frog Xenopus, which produce thousands of giant eggs and embryos that can be manipulated ex vivo. Additionally, we use different Xenopus species with varying genome copy number (ploidy), allowing us dissect the natural mechanisms of adaptation to huge changes in genome size.

To tackle these questions, we use a combination of advanced microscopy, biochemistry, embryology, molecular biology and genomics to create physical models of 3D genome organization and dynamics. Ultimately our work will significantly advance our understanding of the physical limitations of genome evolution, creating testable hypotheses for how these rules are bent or broken in cancer cells with abnormally large genomes