Potato (Solanum tuberosum L.) tuber ageing induces changes in the proteome and antioxidants associated with the sprouting pattern.
During post-harvest storage, potato tubers age as they undergo an evolution of their physiological state influencing their sprouting pattern. In the present study, physiological and biochemical approaches were combined to provide new insights on potato (Solanum tuberosum L. cv. Désirée) tuber ageing. An increase in the physiological age index (PAI) value from 0.14 to 0.83 occurred during storage at 4 degrees C over 270 d. Using this reference frame, a proteomic approach was followed based on two-dimensional electrophoresis. In the experimental conditions of this study, a marked proteolysis of patatin occurred after the PAI reached a value of 0.6. In parallel, several glycolytic enzymes were up-regulated and cellular components influencing protein conformation and the response to stress were altered. The equilibrium between the 20S and 26S forms of the proteasome was modified, the 20S form that recycles oxidized proteins being up-regulated. Two proteins belonging to the cytoskeleton were also differentially expressed during ageing. As most of these changes are also observed in an oxidative stress context, an approach focused on antioxidant compounds and enzymes as well as oxidative damage on polyunsaturated fatty acids and proteins was conducted. All the changes observed during ageing seemed to allow the potato tubers to maintain their radical scavenging activity until the end of the storage period as no accumulation of oxidative damage was observed. These data are interpreted considering the impact of reactive oxygen species on the development and the behaviour of other plant systems undergoing ageing or senescence processes.
Delaplace
Pierre
P
Gembloux Agricultural University, Plant Biology Unit, Avenue de la Faculté d'Agronomie 2A, 5030 Gembloux, Belgium. delaplace.p@fsagx.ac.be
Fauconnier
Marie-Laure
ML
Sergeant
Kjell
K
Dierick
Jean-François
JF
Oufir
Mouhssin
M
van der Wal
Froukje
F
America
Antoine H P
AH
Renaut
Jenny
J
Hausman
Jean-François
JF
du Jardin
Patrick
P
D000975:Antioxidants / Q000378:metabolism*; D060387:Ascorbate Peroxidases; D002374:Catalase / Q000378:metabolism; D015536:Down-Regulation; D015180:Electrophoresis, Gel, Two-Dimensional; D004951:Esterification; D016166:Free Radical Scavengers / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D007700:Kinetics; D054883:Oxylipins / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism; D010636:Phenols / Q000378:metabolism; D035281:Plant Tubers / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism*; D050050:Protein Carbonylation; D020543:Proteome / Q000378:metabolism*; D011198:Solanum tuberosum / Q000201:enzymology / Q000254:growth & development* / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors; D015854:Up-Regulation
D000975:Antioxidants; D016166:Free Radical Scavengers; D054883:Oxylipins; D010636:Phenols; D020543:Proteome; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione