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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

specific cell types from sectioned specimens of heterogeneous tissues

(Longuespee et al., 2014). LCM has been successfully applied in rice (Kubo

et al., 2013). The FIFFF (Flow Field-Flow Fractionation) method is an

elution-based separation method for separating biological macromolecules

without focusing on sample components. The ribosome profiles of Nicotiana

benthamiana were studied using asymmetric FlFFF. It is used to isolate free

molecules of complete and subunits of ribosomes under optimal working

circumstances (Pitkanen et al., 2014). Another method, FFE (free flow

electrophoresis) with two-phase partitioning has been developed to create

a population of highly pure plasma membrane vesicles. This high-quality

plasma membrane separation approach resulted in a consistent proteomic

library of approximately 700 plasma membrane proteins, including periph­

eral membrane proteins not previously discovered by Michele et al. (2016).

Furthermore, chemical proteomics allows for efficient proteome analysis in a

natural setting. For intracellular and subcellular proteomic analysis, activity-

based protein profiling (ABPP) (Wiedner et al., 2014), engineered ascor­

bate peroxidase (APEX) (Rhee et al., 2013), organelle-locatable reactive

molecules (ORMs) (Yasueda et al., 2016), and proximity-dependent biotin

identification (BioID) (Sage et al., 2016) have been developed (Table 13.2).

13.3 ORGANELLE PROTEOME

Analyzes of an organelle’s proteins are an effective way to figure out how

a cell responds under abiotic stress. Although most organelle proteins are

nuclear-encoded, certain organelles, such as chloroplasts and mitochondria,

have unique genetic material that facilitates them to produce proteins on

their own (Agrawal et al., 2011). The interconnections between organelles in

plant cells are influenced by abiotic stress, which has an impact on protein

regulation and secretion in cellular organelles and compartments. Several

secretory mechanisms implicated in plant cell protein targeting have been

described in response to abiotic stress (Mitoma & Ito, 1992; Furman et al.,

2003). To investigate the organelle proteins involved in the stress response,

particularly those with regulatory or protein targeting functions would signif­

icantly improve our understanding of the cellular stress response (Hossain

et al., 2012). A summary of the key proteins is provided, with changes in

relative abundance under stress in the various compartments (Figure 13.1).

More detailed information on proteomic experiments focused on subcellular

proteomics in abiotic stress-treated plants is provided in Table 13.1, including

the mitochondria, nucleus, chloroplasts, cell wall, and plasma membrane.