Cyclic guanosine monophosphate improves salt tolerance in Solanum lycopersicum

• Published in: Journal of plant research Vol. 137; no. 1; pp. 111 - 124
• Main Authors: Bibi, Gulnaz, Shafique, Iqra, Ali, Sartaj, Ahmad, Raza, Shah, Mohammad Maroof, Naqvi, Tatheer Alam, Zeb, Iftikhar, Maathuis, Frans J. M., Hussain, Jamshaid
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.01.2024; Springer Nature B.V
• Subjects: Abiotic stress; Biomedical and Life Sciences; Cations; Cell signaling; Chlorophyll; Cyclic GMP; Efflux; Electrolyte leakage; Flavonoids; Genes; Guanosine Monophosphate - metabolism; Guanosine Monophosphate - pharmacology; Guanosines; Life Sciences; Membranes; Na+/H+-exchanging ATPase; Nucleotides; Osmotic stress; Permeability; Photosynthesis; Plant Biochemistry; Plant Ecology; Plant Physiology; Plant Sciences; Regular Paper – Physiology/Biochemistry/Molecular and Cellular Biology; Roots; Salinity tolerance; Salt tolerance; Salt Tolerance - genetics; Seedlings; Signal transduction; Sodium chloride; Sodium Chloride - pharmacology; Solanum lycopersicum; Solanum lycopersicum - genetics; Cyclic nucleotide; Electrolyte leakage; Cation fluxes; Salt stress
• ISSN: 0918-9440; 1618-0860
• DOI: 10.1007/s10265-023-01487-z

The cyclic nucleotide cyclic guanosine monophosphate (cGMP) is a powerful cell signaling molecule involved in biotic and abiotic stress perception and signal transduction. In the model plant Arabidopsis thaliana , salt and osmotic stress rapidly induce increase in cGMP which plays role by modulating the activity of monovalent cation transporters, possibly by direct binding to these proteins and by altering the expression of many abiotic stress responsive genes. In a recent study, a membrane permeable analogue of cGMP (8-bromo-cGMP) was found to have a promotive effect on soluble sugar, flavonoids and lignin content, and membrane integrity in Solanum lycopersicum seedlings under salt stress. However, it remains to be elucidated how salt stress affects the endogenous cGMP level in S. lycopersicum and if Br-cGMP-induced improvement in salt tolerance in S. lycopersicum involves altered cation fluxes. The current study was conducted to answer these questions. A rapid increase (within 30 s) in endogenous cGMP level was determined in S. lycopersicum roots after treatment with 100 mM NaCl. Addition of membrane permeable Br-cGMP in growth medium remarkably ameliorated the inhibitory effects of NaCl on seedlings’ growth parameters, chlorophyll content and net photosynthesis rate. In salt stressed plants, Br-cGMP significantly decreased Na + content by reducing its influx and increasing efflux while it improved plants K + content by reducing its efflux and enhancing influx. Furthermore, supplementation with Br-cGMP improved plant’s proline content and total antioxidant capacity, resulting in markedly decreased electrolyte leakage under salt stress. Br-cGMP increased the expression of Na + /H + antiporter genes in roots and shoots of S. lycopersicum growing under salt stress, potentially enhancing plant’s ability to sequester Na + into the vacuole. The findings of this study provide insights into the mechanism of cGMP-induced salt stress tolerance in S. lycopersicum .