[초청강연] Comparative genomics of “extremophyte” relatives of Arabidopsis

Comparative genomics of “extremophyte” relatives of Arabidopsis
Dong-Ha Oh
Biological Sciences, Louisiana State University, Baton Rouge, LA
(current: Computercraft/NCBI contractor)
Extremophyte Arabidopsis-relatives, adapted to harsh environments, offer resources to study innovative
strategies for plant stress tolerance. We propose a comparative genomics framework based on
Brassicaceae species, including two extremophytes, Schrenkiella parvula and Eutrema salsugineum,
originated from the shores of hyper-saline lakes and salt flats, plus representatives of oil crops, the
model plant Arabidopsis thaliana, and other phylogenetically informative species. As a proof-of-
concept, we compared the gene regulatory networks (GRNs) responding to the plant stress hormone
abscisic acid (ABA) among the two extremophytes and two stress-sensitive species. We found a unique
root growth promotion in response to ABA, coupled with lineage-specific modifications of ABA-
responsive gene expression patterns and growth hormone-related GRNs, in S. parvula, signifying a
potential strategy leading to stress resilience. We also developed methods to systematically trace gene
functions showing lineage(s)-specific modifications in gene regulation and curate GRNs among multiple
species with distinct histories of gene duplications. Altogether, we aim to expand the Arabidopsis model
to a multi-species model system where comparative genomics approaches can mine innovations beyond
the spectrum of populations from a single species.