Exposure to cadmium (Cd2+) can result in cell death, but the molecular mechanisms of Cd2+ cytotoxicity in plants are not fully understood. Here, we show that Arabidopsis (Arabidopsis thaliana) cell suspension cultures underwent a process of programmed cell death when exposed to 100 and 150 µM CdCl2 and that this process resembled an accelerated senescence, as suggested by the expression of the marker senescence-associated gene12 (SAG12). CdCl2 treatment was accompanied by a rapid increase in nitric oxide (NO) and phytochelatin synthesis, which continued to be high as long as cells remained viable. Hydrogen peroxide production was a later event and preceded the rise of cell death by about 24 h. Inhibition of NO synthesis by NG-monomethyl-arginine monoacetate resulted in partial prevention of hydrogen peroxide increase, SAG12 expression, and mortality, indicating that NO is actually required for Cd2+-induced cell death. NO also modulated the extent of phytochelatin content, and possibly their function, by S-nitrosylation. These results shed light on the signaling events controlling Cd2+ cytotoxicity in plants.
|Autori:||DE MICHELE R; VURRO E; RIGO C; ELVIRI L.; DI VALENTIN M; COSTA A; CARERI M; ZOTTINI M; SANITÀ DI TOPPI L; LO SCHIAVO F|
|Titolo:||Nitric Oxide is Involved in Cadmium-Induced Programmed Cell Death in Arabidopsis Suspension Cultures|
|Anno del prodotto:||2009|
|Digital Object Identifier (DOI):||10.1104/pp.108.133397|
|Appare nelle tipologie:||1.1 Articolo in rivista|