Multiple Patterns of Regulation and Overexpression of a Ribonuclease-Like Pathogenesis-Related Protein Gene, OsPR10a, Conferring Disease Resistance in Rice and Arabidopsis

PLoS One. 2016 Jun 3;11(6):e0156414. doi: 10.1371/journal.pone.0156414. eCollection 2016.

Abstract

An abundant 17 kDa RNase, encoded by OsPR10a (also known as PBZ1), was purified from Pi-starved rice suspension-cultured cells. Biochemical analysis showed that the range of optimal temperature for its RNase activity was 40-70°C and the optimum pH was 5.0. Disulfide bond formation and divalent metal ion Mg2+ were required for the RNase activity. The expression of OsPR10a::GUS in transgenic rice was induced upon phosphate (Pi) starvation, wounding, infection by the pathogen Xanthomonas oryzae pv. oryzae (Xoo), leaf senescence, anther, style, the style-ovary junction, germinating embryo and shoot. We also provide first evidence in whole-plant system, demonstrated that OsPR10a-overexpressing in rice and Arabidopsis conferred significant level of enhanced resistance to infection by the pathogen Xoo and Xanthomona campestris pv. campestris (Xcc), respectively. Transgenic rice and Arabidopsis overexpressing OsPR10a significantly increased the length of primary root under phosphate deficiency (-Pi) condition. These results showed that OsPR10a might play multiple roles in phosphate recycling in phosphate-starved cells and senescing leaves, and could improve resistance to pathogen infection and/or against chewing insect pests. It is possible that Pi acquisition or homeostasis is associated with plant disease resistance. Our findings suggest that gene regulation of OsPR10a could act as a good model system to unravel the mechanisms behind the correlation between Pi starvation and plant-pathogen interactions, and also provides a potential application in crops disease resistance.

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Disease Resistance / genetics
  • Disease Resistance / physiology
  • Gene Expression Regulation, Plant / genetics
  • Gene Expression Regulation, Plant / physiology
  • Oryza / genetics
  • Oryza / metabolism*
  • Phosphates / metabolism
  • Plant Diseases / microbiology
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism*
  • Ribonucleases / genetics
  • Ribonucleases / metabolism*
  • Xanthomonas / pathogenicity*

Substances

  • Phosphates
  • Plant Proteins
  • Ribonucleases

Grant support

This work was supported by the grants from the Ministry of Science and Technology of the Republic of China (https://www.most.gov.tw/). The grant numbers are NSC-93-2311-B-415-002 and MOST-104-2313-B-415-003. Both grants' recipient is: Dr. Shin-Lon Ho. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.