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Advances in Proteomics Research in Environmental Stress Response in Plants

acrylamide gel-electrophoresis), MALDI-TOF/MS/MS, and LC-MS/MS,

as well as elucidation of protein functions and protein functional networks

in plant metabolic and signaling pathways, is accomplished using protein

mapping, characterization of PTMs and bioinformatic approaches and

databases for protein-protein interaction (Holman et al., 2013; Ahmad et al.,

2016). In this chapter, we discussed the impact of proteomic analysis on the

understanding of the accumulation of stress-related protein along with their

biological function and cellular localization.

13.2 PROTEIN CELLULAR FRACTIONATION AND PURIFICATION

METHODS

Plant cells are made up of a cell wall (ECM: extracellular matrix) is a

component of the symplast (apoplast and cytosol), which is linked to

neighboring cells via plasmodesmata. The plasma membrane separates the

apoplast and symplast environments, serving as a dynamic contact between

them. Symplast includes double-membrane enveloped organelles (nucleus,

plastids, and mitochondria) and single membrane enveloped secretory

vesicular compartments (endoplasmic reticulum (ER), Golgi complex, and

trans-Golgi network (TGN), vacuoles, peroxisomes, glyoxisomes). Every

organelle plays a specific role during plant stress adaptation: the nucleus is

the site of stress signal conversion to gene expression, whereas mitochondria

and chloroplasts are the localities of aerobic metabolism, which is essential

for energy supply during stress acclimation. However, Proteomic research

on the organelle response to stress is still in its early stages. Cellular frac­

tionation is an effective strategy for reducing the complexity of cellular

proteomes. As a result, in entire proteome extracts, low-abundant organellar

proteins are often masked by high-abundant cytosolic proteins.

Centrifugation-based and affinity purification-based approaches are

typical applications for subcellular separation and purification. These

methods are rather time-consuming, take quite a long time and make it very

difficult to get pure fractions. To address the limitations of the preceding

approaches, a subcellular separation technique based on several separation

principles has been developed (Table 13.1). Newly developed proteomic

techniques have revealed a lot of information. This research has enhanced

our understanding of the unique proteomic activity of certain organs, which

will aid our understanding of how plants acquire abiotic stress tolerance.

For example, Laser capture microdissection (LCM) is a potential sampling

approach that uses direct microscopic vision and a laser beam to identify