The Arabidopsis peptide kiss of death is an inducer of programmed cell death.

Abstract

Programmed cell death (PCD) has a key role in defence and development of all multicellular organisms. In plants, there is a large gap in our knowledge of the molecular machinery involved at the various stages of PCD, especially the early steps. Here, we identify kiss of death (KOD) encoding a 25-amino-acid peptide that activates a PCD pathway in Arabidopsis thaliana. Two mutant alleles of KOD exhibited a reduced PCD of the suspensor, a single file of cells that support embryo development, and a reduced PCD of root hairs after a 55°C heat shock. KOD expression was found to be inducible by biotic and abiotic stresses. Furthermore, KOD expression was sufficient to cause death in leaves or seedlings and to activate caspase-like activities. In addition, KOD-induced PCD required light in leaves and was repressed by the PCD-suppressor genes AtBax inhibitor 1 and p35. KOD expression resulted in depolarization of the mitochondrial membrane, placing KOD above mitochondria dysfunction, an early step in plant PCD. A KOD∷GFP fusion, however, localized in the cytosol of cells and not mitochondria.

• Authors: Robert Blanvillain, Bennett Young, Yao-min Cai, Valérie Hecht, Fabrice Varoquaux, Valérie Delorme, Jean-Marc Lancelin, Michel Delseny, Patrick Gallois
• Journal: The EMBO journal (EMBO J) Vol. 30 Issue 6 Pg. 1173-83 (Mar 16 2011) ISSN: 1460-2075 [Electronic] England
• PMID: 21326210 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Arabidopsis Proteins
• Mutant Proteins
• Peptides

Topics

• Apoptosis
• Arabidopsis (metabolism)
• Arabidopsis Proteins (genetics, metabolism)
• Hot Temperature
• Membrane Potential, Mitochondrial
• Mitochondrial Membranes (physiology)
• Mutant Proteins (genetics, metabolism)
• Peptides (genetics, metabolism)
• Plant Leaves (metabolism)
• Seedlings (metabolism)