Abstract Detail

Comparative Genomics/Transcriptomics

Buell, C. Robin [1], Crisovan, Emily [2], Dudareva, Natalia [3], Garcia, Nicolas [4], Godden, Grant [5], Henry, Laura [6], Kamileen, Mohamed O. [7], Kates, Heather [8], Kilgore, Matthew B. [6], Lichman, Benjamin R. [7], Mavrodiev, Evgeny [9], Newton, Linsey [2], Rodriguez-Lopez, Carlos [7], O'Connor, Sarah E. [7], Soltis, Douglas [10], Soltis, Pamela S. [11], Vaillancourt, Brieanne [12], Wiegert-Rininger, Krystle [12], Zhao, Dongyan [12].

Transcriptomics, phylogeny, and biochemistry elucidate evolution of chemical diversity and complexity in Lamiaceae.

Plants synthesize an astonishing array of structurally and functionally diverse chemical compounds, which can enhance plant fitness or confer adaptations to specific ecological niches. These specialized metabolites serve as attractants of beneficial organisms and defend plants against biotic or abiotic agents that hinder their growth, survival, or reproduction. Given their important biological functions, chemical complexity can play a major role in the diversification of many plant lineages, with novel compounds serving as key innovations.
Specialized metabolites often originate from a small group of precursors from primary metabolism, which are modified via multistep metabolic pathways to yield a multitude of distinct end-products. Terpenes [e.g. monoterpenes, sesquiterpenes, and iridoids (non-canonical monoterpenes)] are an outstanding example of this process. All are derived from the same precursors, but through an initial scaffold formation and subsequent modifications, a wide variety of chemical structures and properties are produced. This plant metabolite diversity may evolve via gene or genome duplication, followed by sub- or neo-functionalization, an increase of enzyme promiscuity, and/or utilization of scaffold-decorating enzymes. However, the selective pressures responsible for generating specialized metabolite diversity, as well as the biochemical, molecular, and genetic mechanisms by which this metabolite diversity evolves within (or across) plant lineages, remain largely unknown.
We formed the Mint Evolutionary Genomics Consortium—a multi-institutional collaboration combining expertise in genomics, evolutionary biology, and biochemistry—and investigated the evolution of specialized metabolites in the mint family (Lamiaceae), a clade of ca. 7200 species that is renowned for its terpenoid diversity. For Phase I of our project, we combined analyses of leaf transcriptome data from 48 Lamiaceae and four outgroup species with a robust phylogeny and chemical analyses of three terpenoid classes (monoterpenes, sesquiterpenes, and iridoids) that share and compete for precursors. Our integrated chemical-genomic-phylogenetic approach revealed several mechanisms controlling chemical presence/absence and diversity in leaf tissue. We will provide an overview of important Phase I results and discuss our plans and progress on future project phases designed to elucidate patterns and processes of chemical evolution in the mint family.

Related Links:
Mint Genome Project

1 - Michigan State University, Department of Plant Biology, 612 Wilson Road, Rm 166, East Lansing, MI, 48824, USA
2 - Michigan State University, Department of Plant Biology, 612 Wilson Road, Rm 166, East Lansing, MI, 48824, United States
3 - Purdue University, Department of Biochemistry, WSLR, room B030, 175 S. University Street, West Lafayette, IN, 47907-2063, USA
4 - Universidad De Chile, Herbario EIF, Av. Santa Rosa 11315, La Pintana, Santiago, 8820808, Chile
5 - University Of Florida, Florida Museum Of Natural History, Dickinson Hall, PO Box 117800, Gainesville, FL, 32611, United States
6 - Purdue University, WSLR, room B030, 175 S. University Street, West Lafayette, IN, 47907-2063, United States
7 - The John Innes Centre, Department of Biological Chemistry, Norwich, NR4 7UH, UK
8 - University of Florida, PO Box 117800, Gainesville, FL, 32611-7800, United States
9 - Florida Natural History Museum, Florida Museum Of Natural History PO Box 117800, Gainesville, FL, 32611, United States
10 - Florida Museum of Natural History, University of Florida, 1659 Museum Road, Gainesville, Florida, 32611, United States
11 - University Of Florida, Florida Museum Of Natural History, Po Box 117800, Gainesville, FL, 32611, United States
12 - Michigan State University, 612 Wilson Road, Rm 166, East Lansing, MI, 48824, United States

Keywords:
Lamiaceae
transcriptomes
Genomics
Specialized metabolism
monoterpenes
sesquiterpenes
iridoids
phylogeny
Biochemistry.

Presentation Type: Oral Paper
Session: 21, Comparative Genomics and Transcriptomics I
Location: 102/Mayo Civic Center
Date: Tuesday, July 24th, 2018
Time: 9:15 AM
Number: 21006
Abstract ID:954
Candidate for Awards:Margaret Menzel Award