Inferring roles in defense from metabolic allocation of rice diterpenoids

Xuan Lu, Juan Zhang, Benjamin Brown, Riqing Li, Julio Rodriguez-Romero, Aileen Berasategui, Bo Liu, Meimei Xu, Dangping Luo, Zhiqiang Pan, Scott R. Baerson, Jonathan Gershenzon, Zhaohu Li, Ane Sesma, Bing Yang, Reuben J. Peters

Research output: Contribution to journalArticlepeer-review

31 Citations (Scopus)

Abstract

Among their responses to microbial infection, plants deploy an arsenal of natural antibiotic products. Historically these have been identified on the basis of their antibiotic activity in vitro, which leaves open the question of their relevance to defense in planta. The vast majority of such natural products from the important crop plant rice (Oryza sativa) are diterpenoids whose biosynthesis proceeds via either ent- or syn-copalyl diphosphate (CPP) intermediates, which were isolated on the basis of their antibiotic activity against the fungal blast pathogen Magnaporthe oryzae. However, rice plants in which the gene for the syn-CPP synthase Os-CPS4 is knocked out do not exhibit increased susceptibility to M. oryzae. Here, we show that knocking out or knocking down Os-CPS4 actually decreases susceptibility to the bacterial leaf blight pathogen Xanthomonas oryzae. By contrast, genetic manipulation of the gene for the ent-CPP synthase Os-CPS2 alters susceptibility to both M. oryzae and X. oryzae. Despite the secretion of diterpenoids dependent on Os-CPS2 or Os-CPS4 from roots, neither knockout exhibited significant changes in the composition of their rhizosphere bacterial communities. Nevertheless, rice plants allocate substantial metabolic resources toward syn- as well as ent-CPP derived diterpenoids upon infection/induction. Further investigation revealed that Os-CPS4 plays a role in fungal non-host disease resistance. Thus, examination of metabolic allocation provides important clues into physiological function.

Original languageEnglish
Pages (from-to)1119-1131
Number of pages13
JournalPlant Cell
Volume30
Issue number5
DOIs
Publication statusPublished - May 2018

Keywords

  • COPALYL DIPHOSPHATE SYNTHASES
  • PHYTOALEXIN BIOSYNTHETIC GENE
  • ORYZA-SATIVA L
  • ENT-COPALYL
  • DITERPENE PHYTOALEXIN
  • ARABIDOPSIS-THALIANA
  • BLAST FUNGUS
  • IDENTIFICATION
  • PLANTS
  • MOMILACTONES

Cite this