AUTHOR=Sato Yasuhiro , Tezuka Ayumi , Kashima Makoto , Deguchi Ayumi , Shimizu-Inatsugi Rie , Yamazaki Misako , Shimizu Kentaro K. , Nagano Atsushi J. 

TITLE=Transcriptional Variation in Glucosinolate Biosynthetic Genes and Inducible Responses to Aphid Herbivory on Field-Grown Arabidopsis thaliana

JOURNAL=Frontiers in Genetics

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2019.00787

DOI=10.3389/fgene.2019.00787

ISSN=1664-8021

ABSTRACT=<p>Recently, increasing attempts have been made to understand how plant genes function <italic>in natura</italic>. In this context, transcriptional profiles represent plant physiological status in response to environmental stimuli. Herein, we combined high-throughput RNA-Seq with insect survey data on 19 accessions of <italic>Arabidopsis thaliana</italic> grown at a field site in Switzerland. We found that genes with the gene ontology (GO) annotations of “glucosinolate biosynthetic process” and “response to insects” were most significantly enriched, and the expression of these genes was highly variable among plant accessions. Nearly half of the total expression variation in the glucosinolate biosynthetic genes (<italic>AOP</italic>s, <italic>ESM1</italic>, <italic>ESP</italic>, and <italic>TGG1</italic>) was explained by among-accession variation. Of these genes, the expression level of <italic>AOP3</italic> differed among Col-0 accession individuals depending on the abundance of the mustard aphid (<italic>Lipaphis erysimi</italic>). We also found that the expression of the major <italic>cis</italic>-jasmone activated gene <italic>CYP81D11</italic> was positively correlated with the number of flea beetles (<italic>Phyllotreta striolata</italic> and <italic>Phyllotreta atra</italic>). Combined with the field RNA-Seq data, bioassays confirmed that <italic>AOP3</italic> was up-regulated in response to attack by mustard aphids. The combined results from RNA-Seq and our ecological survey illustrate the feasibility of using field transcriptomics to detect an inducible defense, providing a first step towards an <italic>in natura</italic> understanding of biotic interactions involving phenotypic plasticity.</p>