Plant voltage-dependent anion channels are involved in host defense against Pseudomonas cichorii and in Bax-induced cell death

Plant Cell Rep. 2009 Jan;28(1):41-51. doi: 10.1007/s00299-008-0630-x. Epub 2008 Oct 25.

Abstract

The voltage-dependent anion channel (VDAC) is a major outer mitochondrial membrane protein. It is well documented that VDAC plays an important role in apoptosis, a kind of programmed cell death, in mammalian systems. However, little is known about the role of the plant counterpart during the process of plant-specific cell death such as pathogen-induced hypersensitive response. To address this issue, we isolated three VDAC full-length cDNAs (NtVDAC1-3) from Nicotiana tabacum. The deduced products, NtVDACs, share 78-85% identity and retain the conserved eukaryotic mitochondrial porin signature distal to their C-terminal regions. Mitochondrial localization of three NtVDACs in plant cells was confirmed via a green fluorescent protein fusion method. Then, we addressed the main issue concerning pathogenesis relation. The N. benthamiana orthologues of NtVDACs were upregulated by challenge with the non-host pathogen Pseudomonas cichorii, but not after challenge with the virulent pathogen P. syringae pv. tabaci. Both the pharmaceutical inhibition of VDAC and silencing of NbVDACs genes compromised the non-host resistance against P. cichorii, suggesting the involvement of VDACs in defense against non-host pathogen. Involvement of NbVDACs in Bax-mediated cell death was also verified using a similar approach.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Cell Death / physiology*
  • DNA, Complementary / genetics
  • Gene Expression Regulation, Plant
  • Gene Silencing
  • Hydrogen Peroxide / analysis
  • Mitochondria / metabolism
  • Molecular Sequence Data
  • Nicotiana / genetics*
  • Nicotiana / metabolism
  • Nicotiana / microbiology
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Pseudomonas / pathogenicity*
  • RNA, Plant / genetics
  • Sequence Alignment
  • Voltage-Dependent Anion Channels / genetics
  • Voltage-Dependent Anion Channels / metabolism*
  • bcl-2-Associated X Protein / metabolism*

Substances

  • DNA, Complementary
  • Plant Proteins
  • RNA, Plant
  • Voltage-Dependent Anion Channels
  • bcl-2-Associated X Protein
  • Hydrogen Peroxide

Associated data

  • GENBANK/AB286176
  • GENBANK/AB286177
  • GENBANK/AB286178