Abstract Detail

Recent Topics Posters

Smith, Laramie [1], Carey, Sarah [2], Hale, Haley [3], Goertzen, Leslie [4], Harkess, Alex [5].

Morella as a model system for studying the evolution of dioecy, specialized metabolites, and non-leguminous nitrogen fixation.

The future of integrating novel traits into major crops depends on high-quality reference genomes of the species that display these unique phenotypes in nature. The genus Morella harbors clades of globally dispersed species that exhibit a combination of valuable traits relevant to bioenergy and crop-enhancement efforts. These species share a dioecious reproductive strategy and the ability to fix nitrogen via symbiotic nodulation with the actinobacteria Frankia, but frequently differ in the specialized metabolite profiles of their leaves and fruits. Not only would sequencing Morella species offer an opportunity to study the evolution of sex chromosomes within the order Fagales, but it would provide a strong foundation for enriching our understanding of the phenomenon of non-leguminous nitrogen fixation in actinorhizal plants. Nitrogen fixation is critical to commercial agriculture and successful reforestation initiatives, so developing excellent reference genomes for species like this would hasten our endeavors to engineer this trait into other plants. Therefore, we are compiling a reference genome for Morella cerifera, “Southern bayberry,” to serve as the cornerstone for subsequent genetic analyses and the development of this genus as a model system. Initial analysis with OrthoFinder of the genome of Morella rubra, a close relative of M. cerifera, supports previous research suggesting that members of this genus share a common symbiotic signaling pathway for nodulation. However, gene gains and losses specific to nodulating legumes are not shared by nodulating non-legumes, such as the expansion of the chalcone synthase (CHS) gene in Medicago truncatula and Glycine max but not M. rubra. As the first committed enzyme in the flavonoid biosynthetic pathway, CHS plays a critical role in producing the flavonoids necessary for pre-infection signaling in all nodulating species. Expansions of genes like this can create redundancy that may contribute to a dosage effect or even neofunctionalization. Further examination of Morella species may reveal gene expansions and contractions that will help explain the emergence of the unique traits within this genus, bringing us one step closer to the engineering of artificial nodulation systems as well as controlling sexual systems or specific metabolite production in crops.

1 - HudsonAlpha Institute for Biotechnology, 601 Genome Way, Huntsville, Alabama, 35806, United States
2 - Auburn University, Department of Crop, Soil, and Environmental Sciences, Auburn, AL, USA
3 - HudsonAlpha Institute for Biotechnology, Harkess Lab, 601 Genome Way, Huntsville, Alabama, 35806, United States
4 - Auburn University, Department of Biological Sciences, 101 Rouse Life Sciences Bldg., Auburn, AL, 36849, USA
5 - Auburn University, Department of Crop, Soil, and Environmental Sciences, Crop, Soil & Environmental Sciences Department, Auburn, Alabama, USA

Keywords:
Dioecy
nitrogen fixation
nodulation
Model System
specialized metabolites
Myricaceae.

Presentation Type: Recent Topics Poster
Session: P1, Recent Topics Posters
Location: Virtual/Virtual
Date: Thursday, July 22nd, 2021
Time: 5:00 PM(EDT)
Number: P1RT033
Abstract ID:1424
Candidate for Awards:None