A central goal in evolutionary developmental biology is to understand how diverse animal cell types have evolved. The innate immune system, which includes immune cells and inflammatory molecules, represents the first line of defense against invading pathogens. The emergence of immunity, the ability to recognize self vs nonself, is integral to the evolution of multicellular life. This project uses recently developed genetic techniques to characterize immune cells and their responses to pathogens in a model ctenophore. The ctenophores, or â€comb jellies,â€ represent one of the most ancient branches of the animal tree of life. The data produced by this project will shed light on the early evolution of immunity in animals. Outreach components of this project include the development of a hands-on cell biology based learning module for several Miami-Dade County K-12 schools that serve underrepresented and economically disadvantaged students. This project also includes a mentored research internship for Miami-Dade Community College students from underrepresented groups.
The recognition of self vs nonself, or immunity, is critical to the maintenance of multicellularity. A significant knowledge gap exists regarding immune system biology in non-bilaterian animals. This project seeks to improve our understanding of innate immunity evolution in animals by characterizing both immune system response and immune cell specification in the model ctenophore, Mnemiopsis leidyi. The goals of this project include: 1) defining immune cell types present in Mnemiopsis, 2) assessing transcriptional responses to discrete immune challenges through both bulk and single-cell transcriptomics, and 3) determining the functional role of the transcription factor Interferon Regulatory Factor (IRF) in immune cell development/specification using CRISPR/Cas9 genome editing. This project's experimental results will inform several critical outstanding questions relating to metazoan innate immunity. Q1) Does the range of cell types associated with innate immunity in ctenophores reflect an early establishment and diversification of immune cell type diversity in the animal stem lineage? Q2) Do immune cells in ctenophores utilize conserved or divergent networks of gene expression both during immune cell development and innate immunity responses to microbial pathogens? Q3) Do novel traits associated with immune cells in Mnemiopsis reflect unique adaptations to pathogens present in their preferred estuary/coastal environments? This work will reveal conserved aspects of pathogen defense mechanisms and immune cell specification associated with the evolution of metazoan innate immunity and reveal potential novel ctenophore-specific aspects of pathogen defense and immune cell type diversity.
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.