Rice suspension cultured cells are evaluated as a model system to study salt responsive networks in plants using a combined proteomic and metabolomic profiling approach

Abstract

Salinity is one of the major abiotic stresses affecting plant productivity but surprisingly, a thorough understanding of the salt-responsive networks responsible for sustaining growth and maintaining crop yield remains a significant challenge. Rice suspension culture cells (SCCs), a single cell type, were evaluated as a model system as they provide a ready source of a homogenous cell type and avoid the complications of multicellular tissue types in planta. A combination of growth performance, and transcriptional analyses using known salt-induced genes was performed on control and 100 mM NaCl cultured cells to validate the biological system. Protein profiling was conducted using both DIGE- and iTRAQ-based proteomics approaches. In total, 106 proteins were identified in DIGE experiments and 521 proteins in iTRAQ experiments with 58 proteins common to both approaches. Metabolomic analysis provided insights into both developmental changes and salt-induced changes of rice SCCs at the metabolite level; 134 known metabolites were identified, including 30 amines and amides, 40 organic acids, 40 sugars, sugar acids and sugar alcohols, 21 fatty acids and sterols, and 3 miscellaneous compounds. Our results from proteomic and metabolomic studies indicate that the salt-responsive networks of rice SCCs are extremely complex and share some similarities with thee cellular responses observed in planta. For instance, carbohydrate and energy metabolism pathways, redox signaling pathways, auxin/indole-3-acetic acid pathways and biosynthesis pathways for osmoprotectants are all salt responsive in SCCs enabling cells to maintain cellular function under stress condition. These data are discussed in the context of our understanding of in planta salt-responses.

Distinct gene networks drive differential response to abrupt or gradual water deficit in potato

“…Cell cultures are valuable tools to elucidate the complexity of the mechanisms of transduction of exogenous signals, allowing focusing on the biochemistry and cell physiology underlying the maintenance of homeostasis under stress conditions (Grillo et al, 1996;Takahashi et al, 2004). Although the experimental system used represents a simplification of physiological mechanisms adopted by plants, it has been widely demonstrated that the use of plant cell cultures can boost the comprehension of plant-environment interaction (Costa et al, 2010;Dubrovina et al, 2015;Larosa et al, 1987;Liu et al, 2013).…”

Quantitative Proteomic Analysis of the Rice (Oryza sativa L.) Salt Response

“…Antioxidant related proteins were also detected in previous proteomic studies. In suspension-cultured rice cells under salt stress, GST and glutaredoxin (GRX) contents were down-regulated; however, no change in TRX levels was observed [ 22 ]. Similarly, putative TPx, TRX M-like, putative GSTF3 and TRX x proteins were found down-regulated in our study.…”

“…identified 18 salt stress response proteins [ 21 ]. Recently, an isobaric Tags for Relative and Absolute Quantitation (iTRAQ) approach identified at least 521 proteins that responded to salt stress in suspension-cultured rice cells [ 22 ]. To date, there have been no reports investigating the rice shoot proteome under conditions of salt stress using quantitative proteomic methods.…”

Ion‐dependent metabolic responses of Vicia faba L. to salt stress

“…Higher Na + and Cl − concentrations are harmful for photosynthesis and cause a developmental disturbance of plants that is associated with osmotic imbalance and toxic ionic effects plus other nutritional imbalances, such as those of potassium and calcium, and oxidative stress (Geilfus et al, 2015;Munns & Tester, 2008;Nazar, Iqbal, Masood, Syeed, & Khan, 2011). Metabolic responses to salt stress have been studied in model plants such as Arabidopsis (Kim, Bamba, Harada, Fukusaki, & Kobayashi, 2007;Zhang, Zhang, Du, Chen, & Tang, 2011), in diverse crops such as Oryza sativa and Zea mays (Liu et al, 2013;Richter, Erban, Kopka, & Zörb, 2015;Sanchez, Siahpoosh, Roessner, Udvardi, & Kopka, 2008), and in leguminous plants including V. faba, Cicer arietinum, and Lotus japonicus (Dias et al, 2015;Geilfus et al, 2015;Sanchez, Pieckenstain, Escaray, et al, 2011), demonstrating a complex tissue response to NaCl. Diverse metabolomic traits are associated with enhanced NaCl tolerance (Del-Saz et al, 2016;Richter et al, 2015;Sanchez, Pieckenstain, Escaray, et al, 2011;Widodo et al, 2009).…”