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Advances in Proteomics Research in Environmental Stress Response in Plants

13.3.1 NUCLEUS

The nucleus is the most critical organelle for controlling protein expression,

which is crucial for regulating plant response to abiotic stress. The nuclear

protein collaborates along with nucleotide polymers to serve important roles

in the nucleus. Furthermore, inside the nucleus, there is a complex network

of processes that respond to stress. The discovery of novel nuclear proteins

aids our understanding of protein function in providing physiological stress

tolerance. There is currently limited information on the proteomic analysis

of stress-responsive nuclear protein expression profiles in plants.

The nuclear proteome analysis of model plant Arabidopsis response was

analyzed under cold stress using 2-DE and MALDI-TOF/MS, respectively.

So far, 184 protein spots have been discovered, with 158 of them being

involved in a wide range of biological functions. In this, 54 were up-or

down-regulated by more than a factor of two. ABA-dependent and ABA-

independent transcription factors such as bZIP (basic-region leucine-zipper),

bHLH (basic helix-loop-helix), MYB, NAC, and others were also revealed

to have known stress response-related motifs or activity (Bae et al., 2003). In

addition, expression of the 60S ribosomal protein, small nuclear ribonucleo­

protein A’ (U2 snRNP-A’), and Hsc70-1 (heat-shock protein chaperon 70-1)

was stimulated.

The nuclear proteome of drought-treated chickpea to obtain a good under­

standing of the molecular mechanisms that represent dehydration-responsive

adaptation (Pandey et al., 2008). They identified a total of 205 differentially

regulated protein spots, among them 147 differentially expressed proteins

involved in gene expression, signal transmission, chaperones, chromatin

remodeling, ROS scavenging enzymes, and nucleocytoplasmic transport and

Ran-binding protein (RanBP).

To understand a better knowledge of the molecular pathways that repre­

sent dehydration-responsive adaptation, a comparable drought-responsive

nuclear proteome investigation was carried out in rice (Choudhary et al.,

2009). They discovered 109 proteins that are believed to be involved in tran­

scriptional control, chromatin remodeling, signaling, and gene regulation,

cell defense and rescue, and protein degradation, among other functions.

They also revealed a differential display of nuclear proteome of 150 protein

spots whose intensities varied substantially over the dehydration period.

The presence of 27 phosphoproteins controlled by ABA and phosphory­

lated in response to flooding was discovered in research of nuclear phos­

phoproteins in soybean root tip during flooding, including zinc-finger/BTB