NSF Postdoctoral Fellowship in Biology FY 2021: Environmental influence and mechanisms underlying subgenome dominance in Camelina sativa

This action funds an NSF Plant Genome Postdoctoral Research Fellowship in Biology for FY 2021. The fellowship supports a research and training plan in a host laboratory for the Fellow who also presents a plan to broaden participation in biology. The title of the research and training plan for this fellowship to Dr.

Jordan Brock is "Environmental influence and mechanisms underlying subgenome dominance in Camelina sativa". The host institutions for the fellowship are Michigan State University and Boyce Thompson Institute and the sponsoring scientists are Dr. Patrick Edger and Dr. Andrew Nelson.

Many agriculturally important plants are the product of hybridization events in which the genomes of two or more parental species come together to form a new species (e.g., canola, cotton, or wheat). These plants, known as polyploids, are often more resistant to environmental stress because they have multiple copies of each gene (from their parental subgenomes) providing a larger toolkit for overcoming challenges.

However, little is known about the degree to which polyploids preferentially utilize genes of different parental origin to overcome environmental challenges. This project will address the role parental subgenomes play in overcoming environmental stresses in the polyploid biofuel crop, camelina. Specifically, this work will address the role of temperature in determining subgenome bias in seed oil production.

Through interrogation of the mechanisms behind environmentally determined responses by the underlying genetics encoded by each subgenome, this work will provide the genomic understanding and resources for the development of more resilient crops. The fellow will receive technical training in genomics, epigenomics, and bioinformatics. Outreach in plant biology and genomics will be conducted in K-12 schools through a biofuel education module, in addition to the mentoring and training of undergraduate researchers.

This project aims to use genomic techniques to understand the relative contribution of each subgenome in the regulation of abiotic stress (temperature) with regard to seed oil production in Camelina sativa. Camelina, an emerging aviation biofuel crop, is the product of a hybridization and whole-genome duplication between two parental species, C. hispida and C. neglecta.

The quality and composition of camelina oil is known to be influenced greatly by environmental conditions such as temperature. This project will employ transcriptome and bisulfite sequencing to understand how expression-levels among subgenomes change relative to each other as a consequence of temperature stress. Camelina sativa and its two diploid parental species will be grown together in varying environmental conditions and developing seeds will be extracted at multiple timepoints.

Transcriptome and DNA methylation libraries will be sequenced across distinct developmental stages of the seed, and in varying environments, to examine subgenome-specific contributions. One hypothesis is that polyploid plants have the ability to regulate subgenome expression such that the subgenome most adapted to the current environment will be more dominantly expressed.

Additionally, DNA methylation patterns across C. sativa subgenomes will be examined to understand the mechanisms behind subgenome expression level dominance. Data generated in this project will be presented in peer-reviewed publications, and transcriptomic and epigenomic data generated will be made publicly available in National Center for Biotechnology Information databases. All other data, including phenotypic data, will be made publicly available in Dryad.

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.