Postdoctoral Fellowship: PRFB: Meiofaunal methylation- Exploring Epigenetic Influences on Heterochronic Shifts in Development

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2024, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment, and Phenotypes. The fellowship supports research and training of the fellow who will contribute to the area of Rules of Life in innovative ways. Sediment covering the ocean floor is one of the most widespread habitats on earth, and it is home to representatives of about one-third of major animal groups across the Tree of Life. In order to live in the spaces between grains of sand, these animals have to be extremely small (less than 0.5 mm in size) and are referred to as meiofauna. Many species of meiofauna evolved from large-bodied ancestors and are secondarily reduced or miniaturized. Miniaturization happens gradually over time or through evolutionary shortcuts, like changes in the timing of development. In the case of these evolutionary shortcuts, the adult miniaturized species resembles the juvenile or larval form of a closely related, large-bodied species. This research will investigate how animals can modify their genomes in order to make drastic changes to their bodies using these evolutionary shortcuts. Understanding the flexibility of animal genomes is important as increased pressure is placed on animals to adapt to rapidly shifting climates. The fellow will also create publicly available activities for educators focusing on increasing ocean and biodiversity literacy in school-age children. Changes in DNA methylation correspond with major developmental transitions and growth but remain largely unexplored in the context of miniaturization. This research will leverage publicly available data with de novo sequencing, experimental manipulation, and in situ hybridization to study DNA methylation over the development of the meiofaunal annelid Dimorphilus gyrociliatus. Key outcomes of this project will be: (1) Define the extent and pattern of DNA methylation in the annelid D. gyrociliatus. (2) Investigate the putative function of 5mC methylation during D. gyrociliatus development through blocking of DNMT1 activity. (3) Investigate the relationship between methylation patterning and heterochronic shifts in hox gene expression in D. gyrociliatus and related macrofaunal annelids. All data will be publicly available to limit barriers to knowledge. The fellow will also participate in career development courses at the host institution in mentorship, project management, and strategic career planning. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.