S-like ribonuclease gene expression in carnivorous plants

Emi Nishimura, Minako Kawahara, Reina Kodaira, Marina Kume, Naoki Arai, Jun ichi Nishikawa, Takashi Ohyama

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

Functions of S-like ribonucleases (RNases) differ considerably from those of S-RNases that function in self-incompatibility. Expression of S-like RNases is usually induced by low nutrition, vermin damage or senescence. However, interestingly, an Australian carnivorous plant Drosera adelae (a sundew), which traps prey with a sticky digestive liquid, abundantly secretes an S-like RNase DA-I in the digestive liquid even in ordinary states. Here, using D. adelae, Dionaea muscipula (Venus flytrap) and Cephalotus follicularis (Australian pitcher plant), we show that carnivorous plants use S-like RNases for carnivory: the gene da-I encoding DA-I and its ortholog cf-I of C. follicularis are highly expressed and constitutively active in each trap/digestion organ, while the ortholog dm-I of D. muscipula becomes highly active after trapping insects. The da-I promoter is unmethylated only in its trap/digestion organ, glandular tentacles (which comprise a small percentage of the weight of the whole plant), but methylated in other organs, which explains the glandular tentacles-specific expression of the gene and indicates a very rare gene regulation system. In contrast, the promoters of dm-I, which shows induced expression, and cf-I, which has constitutive expression, were not methylated in any organs examined. Thus, it seems that the regulatory mechanisms of the da-I, dm-I and cf-I genes differ from each other and do not correlate with the phylogenetic relationship. The current study suggests that under environmental pressure in specific habitats carnivorous plants have managed to evolve their S-like RNase genes to function in carnivory.

Original languageEnglish
Pages (from-to)955-967
Number of pages13
JournalPlanta
Volume238
Issue number5
DOIs
Publication statusPublished - 2013 Nov 1

Keywords

  • Cephalotus follicularis
  • DNA methylation
  • Dionaea muscipula
  • Drosera adelae
  • T2 family ribonucleases
  • Transcription

ASJC Scopus subject areas

  • Genetics
  • Plant Science

Fingerprint Dive into the research topics of 'S-like ribonuclease gene expression in carnivorous plants'. Together they form a unique fingerprint.

  • Cite this

    Nishimura, E., Kawahara, M., Kodaira, R., Kume, M., Arai, N., Nishikawa, J. I., & Ohyama, T. (2013). S-like ribonuclease gene expression in carnivorous plants. Planta, 238(5), 955-967. https://doi.org/10.1007/s00425-013-1945-6