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Advances in Proteomics Research in Environmental Stress Response in Plants

shock proteins and specific losses of other proteins suggest that mitochondria

response to various abiotic stressors is diverse at the protein level.

Mitochondrial proteome during salt stress-induced rice programmed

cell death (PCD). After 2-DE analysis, eight PCD-related proteins include

4 upregulated (Glycoside hydrolase, mitochondrial heat shock protein 70,

20S proteasome subunit, and Cu/Zn-SOD) and four down-regulated (ATP

synthase beta subunit, cytochrome-c oxidase subunit 6b, S-adenosylmethio­

nine synthetase 2, and transcription initiation factor eIF-3 epsilon) proteins

were discovered. According to a proteome analysis, ATP synthase may not

be the primary ATP generator in rice mitochondria during the early stages of

PCD (Chen et al., 2009).

Plant mitochondrial functions have been inhibited by Cd stress was

observed in pea (Smiri et al., 2009). During oxidative stress, Arabidopsis

mitochondria were investigated to learn more about protein interactions with

metal ions and the control of protein activity in plants (Tan et al., 2010).

Their findings showed that mitochondrial metal concentration is dynamic

and varies under oxidative stress and that various proteins have varied metal

affinity and sensitivity to metal ion inactivation. The vulnerability of mito­

chondrial respiratory chain pathways and matrix enzymes to metal-induced

loss of function varied considerably, resulting in selective oxidation events

in the mitochondrial proteome.

Under flooding stress, a thorough study of mitochondrial proteins in

soybean roots and hypocotyls was carried out. 2-DE and blue native-poly­

acrylamide gel electrophoresis (BN-PAGE) were used to separate mitochon­

drial matrix and membrane proteins, respectively (Komatsu et al., 2011).

They observed flooding stress increased proteins and metabolites linked to

the tricarboxylic acid cycle (TCA) and the γ-amino butyrate shunt, whereas

it reduced inner membrane carrier proteins and proteins related to electron

transport chain complexes III, IV, and V. The level of NADH and NAD were

increased whereas, ATP levels considerably decreased. These findings lead

them to the conclusion that flooding stress damages electron transport chains

directly, despite the fact that NADH synthesis rises in the mitochondria via

the TCA cycle (Komatsu et al., 2011).

The mitochondrial proteome and differences associated with salt toler­

ance in two contrasting salinity tolerant and sensitive wheat cultivars were

studied (Jacoby et al., 2010). They identified 68 unique proteins including

Mn-SOD, alternative oxidase (AOX). Cysteine synthase, nucleoside diphos­

phate kinase, and the voltage-dependent anion channel (VDAC). Both

Mn-SOD and AOX are important in scavenging ROS that are produced