Proteasome function is required for activation of programmed cell death in heat shocked tobacco Bright-Yellow 2 cells.
To find out whether and how proteasome is involved in plant programmed cell death (PCD) we measured proteasome function in tobacco cells undergoing PCD as a result of heat shock (HS-PCD). Reactive oxygen species (ROS) production, cytochrome c levels and caspase-3-like protease activation were also measured in the absence or presence of MG132, a proteasome inhibitor. We show that proteasome activation occurs in early phase of HS-PCD upstream of the caspase-like proteases activation; moreover inhibition of proteasome function by MG132 results in prevention of PCD perhaps due to the prevention of ROS production, cytochrome c release and caspase-3-like protease activation.
Vacca
Rosa A
RA
Istituto di Biomembrane e Bioenergetica, Consiglio Nazionale delle Ricerche, Via Amendola 165/A, I-70126 Bari, Italy.
Valenti
Daniela
D
Bobba
Antonella
A
de Pinto
Maria C
MC
Merafina
Riccardo S
RS
De Gara
Laura
L
Passarella
Salvatore
S
Marra
Ersilia
E
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D018869:Heat-Shock Response; D006358:Hot Temperature; D007976:Leupeptins / Q000494:pharmacology; D008928:Mitochondria / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014026:Nicotiana / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*
D007976:Leupeptins; D011480:Protease Inhibitors; D017382:Reactive Oxygen Species; D045304:Cytochromes c; D053148:Caspase 3; D046988:Proteasome Endopeptidase Complex; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde