UNRAVELING THE GENE REGULATORY NETWORKS OF PREDATOR-INDUCED DEVELOPMENTAL PLASTICITY WITHIN AND ACROSS GENERATIONS IN DAPHNIA MAGNA

The dynamic interplay between genetic and environmental factors has long captivated biologists aiming to understand phenotypic variation across environments. Developmental plasticity is a remarkable feature where a genotype may display multiple phenotypes in response to environmental factors, without changes to the DNA sequence. Moreover, developmental plasticity can occur through developmental changes within a single generation, termed within-generation plasticity (WGP), or involve environmental influences on one generation affecting the phenotypic traits of subsequent non-exposed generations, known as transgenerational plasticity (TGP). Daphnia magna is an ideal model for studying developmental plasticity, as its well-documented environmental responses and asexual reproduction enable clear separation of genetic and environmental effects. Notably, Daphnia adjust their morphology, behavior, and life history traits in response to predator cues, showing plasticity within and across generations. Recent research has highlighted gene expression changes during plastic responses, yet the gene regulatory mechanisms and how these connect into gene regulatory networks (GRNs) driving WGP and TGP remains largely unexplored. By combining traditional gene expression assays (RNA-seq) with Assays for Transposase-Accessible Chromatin sequencing (ATAC-seq) to assess gene regulation, this project will investigate the GRNs that control plastic responses to predator cues. Specifically, the project aims to (1) characterize regulatory mechanisms involved in WGP, (2) examine their persistence across generations in TGP, (3) explore small RNAs' role in epigenetic transmission, and (4) compare WGP and TGP. By leveraging Daphnia’s clonal reproduction, short generational cycles, and excellent standing as an ecological model, this study seeks to provide new insights into the epigenetic foundations of plastic development.