RoL:NSF-BSF: IMAGiNE: Temperature acclimation through RNA editing

All the information required to create an organism, and for the organism to sustain its life, is encoded in its DNA. The portion of the information required at any given moment is temporarily copied into RNA before being decoded into the proteins that execute required functions. Molecular systems that manipulate this flow of information have led to some of the most consequential tools for modern biology, from gene cloning technologies to CRISPR genome engineering.

All multicellular animals can edit genetic information as it passes through RNA, however the extent to which they do so varies widely. The coleoid cephalopods (squid, octopus, and cuttlefish) edit RNA at exceptionally high levels, and thus provide ideal models to study the process. Because RNA is a transient molecule, RNA editing is a good tool to create temporary changes that help with environmental acclimation.

The work in this grant seeks to better understand how cephalopod RNA editing is used for temperature acclimation. Using recently developed cephalopod gene knockout technologies, the enzyme(s) that generate high-level RNA editing will be uncovered. In addition, how individual RNA edits affect proteins will be studied.

Finally, the evolutionary underpinnings of RNA editing will be compared between similar squid species that inhabit different thermal environments. This project will enhance STEM education for underrepresented minorities through hands-on workshops on genome editing given to students from the University of Puerto Rico. Outreach on cephalopod biology and RNA editing will be extended to science journalists, and rabbinic leaders from Jewish community.

Most organisms are confronted by a variable thermal environment and temperatures fluctuations are particularly acute for aquatic ectotherms due to the high thermal conductivity of water. All enzymatic reactions are governed by temperature, but the degree of sensitivity varies. Coordinating multiple enzymatic reactions across temperatures is a fundamental physiological challenge.

This proposal focuses on RNA editing through adenosine deamination and how it is used for temperature acclimation. All multicellular metazoans use this process, however the coleoid cephalopods use it most extensively. Transcriptome-wide screens have uncovered tens of thousands of RNA editing sites, and these large data sets provide a unique opportunity to examine how editing is used to fine-tune physiology, and how it evolves.

Taking advantage of recently developed gene knockout methods for cephalopods, the enzymatic underpinnings of high-level recoding will be explored, as well as the molecular basis of its temperature sensitivity. In addition, the work will investigate how temperature sensitive editing sites affect the function of key proteins in neurophysiology and examine how these sites are selected in closely related species from different thermal environments.

This project will enhance STEM education for underrepresented minorities, generate resources for cephalopod biology, and provide diverse community outreach. Workshops on genome editing will be given to students from the University of Puerto Rico. The PIs will create guidelines for the humane and ethical use of cephalopods in research.

Outreach on cephalopod biology and RNA editing will be extended to science journalists, and rabbinic leaders from Jewish community.

This proposal was supported by the Integrative Ecological Physiology Program within the Division of Integrative Organismal Systems, the Genetic Mechanisms Cluster within the Division of Molecular and Cellular Biosciences, and Rules of Life Program within the Directorate for Biological Sciences.

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.