Protein Expression After Nacl Treatment in Two Tomato Cultivars Differing in Salt Tolerance

Abstract

SDS-PAGE electrophoresis was used to study the effect of NaCl on protein expression in two cultivars of tomato (Solanum lycopersicum L.): Edkawi (salt-tolerant) and Castle rock (salt-sensitive). Five-day-old seedlings were grown on MS agar media supplemented with 0, 50, 100, 150, 200 and 300 mM NaCl. Two days after treatment the seedlings were examined to determine the effect of salt on their growth and to relate that to protein banding variations. Gel analysis showed differences in at least 4 protein bands with molecular weights at 20, 25, 45 and 65 kDa. These proteins were induced in the 50 mM NaCl treatment in the salt-sensitive cultivar, then decreasing to undetectability at higher concentrations. In the salt-tolerant cultivar, most of the proteins exhibited a more or less steady expression pattern and maintained expression through the 200 mM NaCl treatment. All proteins gave weak or no expression signals at 300 mM NaCl, the treatment that proved lethal. Differentially expressed bands were identified using MALDI-TOF mass spectrometry. The putative function of each identified protein in relation to salt stress is discussed.K Ke ey y w wo or rd ds s: : SDS-PAGE, salinity, 45 S ribosomal protein, Rubisco, MALDI-TOF mass spectrometry, tomato.

Tomato responses to salinity stress: From morphological traits to genetic changes

“…According to the authors, the accumulation of RbcL at 50 mM NaCl in the cultivar Castle rock might be the result of Rubisco degradation under saline stress, as this cultivar is more sensitive to salinity. The better tolerance to salt stress of cultivar Edkawi is demonstrated by better retention of Rubisco content, chromosome segregation and up-regulation of ion pump proteins (Khalifa, 2012). In another study carried out on the cultivar BINATomato-5 the soluble protein content decreased by 25.64% at 60 mM NaCl and by 42.75% at 120 mM NaCl (Hossain et al, 2012).…”

Exploring glucosinolates diversity in Brassicaceae: a genomic and chemical assessment for deciphering abiotic stress tolerance

“…Extensive studies in Brassicaceae family showed a positive correlation between salt stress and GLS content, [e.g. in broccoli (López-Berenguer et al, 2009), canola (Khalifa, 2012), radish sprouts (Yuan et al, 2010), pakchoi (Keling andZhujun, 2010)]. An increase in the signature of GLS content has also been reported for Brassicaceae taxa under drought stress, namey in Brassica napus (Champolivier and Merrien, 1997), Brassica oleracea (Radovich et al, 2005), Brassica rapa (Zhang et al, 2008), Brassica juncea (Tong et al, 2014), and Brassica carinata (Ngwene et al, 2017).…”

The effect of chitosan–PMAA–NPK nanofertilizer on Pisum sativum plants

“…Proteins were extracted from 5-day-old seedlings after being soaked in the applied concentrations of 1, 0.5. 0.25, 0.125 and 0.0625 R of CS-PMAA-NPK NPs for 48 h as described by Khalifa (2012). Briefly, whole seedlings were ground in liquid nitrogen and then homogenized in Tris-HCl buffer (Sigma-Aldrich, St. Louis, MO, USA) at pH 8 (W/V); 0.1 mM phenylmethyl sulfonylfluoride (PMSF) as protease inhibitor and 100 mM dithiothreitol (DTT) as a reducing agent (instead of mercaptoethanol).…”