The expression of five genes involved in photosynthesis was investigated under different salinity conditions in Dunaliella salina. These genes encodes ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) large and small subunits, major light-harvesting chlorophyll (chl) a/b protein of photosystem II, carbonic anhydrase and adenosine tri phosphate synthase alpha subunit. As D. salina grows in hypersaline conditions, it is important to study expression of these genes in relation to different salinity levels. Changes in the mRNA level under different NaCl conditions were determined using the comparative CT method. Cell number and chl a content were estimated to determine optimal growth at different NaCl concentrations. Real-time PCR results showed enhanced expression of photosynthesis genes upon exposure of D. salina cells from Sambhar Lake to 1.7 M NaCl containing medium. This salinity corresponds to only one-third of the salinity of the Sambhar Lake habitat. In another salt condition, the expression level of all genes was found to be down-regulated at 1.0 M (sub-optimal concentration for growth of D. salina), 2.5 M and 3.0 M NaCl (supra-optimal concentration for growth) when compared with 1.7 M NaCl containing medium as a control. The present study will help in understanding the salinity tolerance in D. salina as a model microalga.
Sharma P, Kothari SL, Kachhwaha S. Expression analysis of photosynthesis genes in Dunaliella salina grown at different NaCl concentrations. J App Biol Biotech, 2015; 3 (06): 015-021. DOI: 10.7324/JABB.2015.3603
1. Jahnke LS, White AL. Long-term hyposaline and hypersaline stresses produce distinct antioxidant responses in the marine alga Dunaliella tertiolecta. Journal of Plant Physiology. 2003; 160:1193–1202.
2. Hasegawa PM, Bressan RA, Zhu J, Bohnert HJ. Plant cellular and molecular responses to high salinity. Annual Review of Plant Physiolgy and Plant Molecular Biology. 2000; 51:463–499.
3. Rochaix JD. Chlamydomonas, a model system for studying the assembly and dynamics of photosynthesis complexes. FEBS Letters. 2002; 529:34–38.
4. Ramos AA, Polle J, Tran D, Cushman JC, Jin ES, Varela JC. The unicellular green alga Dunaliella salina Teod. as a model for abiotic stress tolerance: genetic advances and future perspectives. Algae. 2011; 26:3–20.
5. Kirst GO. Salinity tolerance of eukaryotic marine algae. Annual Review of Plant Biology and Plant Molecular Biology. 1989; 40:21–53.
6. Liska AJ, Shevchenko A, Pick U, Katz A. Enhanced photosynthesis and redox energy production contribute to salinity tolerance in Dunaliella as revealed by homology-based proteomics. Plant Physiology. 2004; 136:2806–2817.
7. Garcia F, Freile-Pelegrin Y, Robledo D. Physiological characterization of Dunaliella sp. (Chlorophyta, Volvocales) from Yucatan, Mexico. Bioresource Technology. 2007; 98:1359–1365.
8. Mishra A, Mandoli A, Jha B. Physiological characterization and stress-induced metabolic responses of Dunaliella salina isolated from salt pan. Journal of Industrial Microbiology and Biotechnology. 2008; 35:1093–1101.
9. Ben-Amotz A, Katz A, Avron M. Accumulation of β-carotene in halotolerant algae: purification and characterization of β-carotene rich globules from Dunaliella bardawil (Chlorophyceae). Journal of Phycology. 1982; 18:529–537.
10. Pisal DS, Lele SS. Carotenoid production from microalga, Dunaliella salina. Indian Journal of Biotechnology. 2005; 4:476–483.
11. Fachet M, Flassig R, Rihko-Struckmann L, Sundmacher K. A dynamic growth model of Dunaliella salina: parameter identification and profile likelihood analysis. Bioresource Technology. 2014; 173:21–31.
12. Cho K, Kim K, Lim N, Kim M, Ha J, Shin H, Kim M, Roh S, Kim D, Oda T. Enhanced biomass and lipid production by supplement of myo-inositol with oceanic microalga Dunaliella salina. Biomass and Bioenergy. 2013; 72:1–7.
13. Xia B, Wang S, Duan J, Bai L. The relationship of glycerol and glycolysis metabolism pathway under hyperosmotic stress in Dunaliella salina. Central European Journal of Biology. 2014; 9:901–908.
14. Tran D, Doan N, Louime C, Giordano M, Portilla S. Growth, antioxidant capacity and total carotene of Dunaliella salina DCCBC15 in a low cost enriched natural seawater medium. World Journal of Microbiology and Biotechnology. 2014; 30:317–322.
15. Kuhlbrandt W, Wang DN, Fugiyoshi Y. Atomic model of plant light-harvesting complex by electron crystallography. Nature. 1994; 367:614–621.
16. Wei L, Cao Y, Bai L, Liang X, Deng T, Li J, Qiao D. Cloning and expression of a gene coding for the major light-harvesting chlorophyll a/b protein of photosystem II in the green alga Dunaliella salina. Journal of Applied Phycology. 2007; 19:89–94.
17. Badger MR, Price GD. The role of carbonic anhydrase in photosynthesis. Annual Review of Plant Physiology and Plant Molecular Biology. 1994; 45:369–392.
18. Suzuki E, Shiraiwa Y, Miyachi S. The cellular and molecular aspects of carbonic anhydrase in photosynthesis microorganisms. In: Round FE, Chapman DJ (eds) Progress in phycological research, vol 10. Biopress, Bristol, UK, 1994; p. 1–54.
19. Gilmour DJ, Hipkins MF, Boney AD. The effect of decreasing the external salinity on the primary processes of photosynthesis in Dunaliella tertiolecta. Journal of Experimental Botany. 1984a; 35:28–35.
20. Fisher M, Gokhman I, Pick U, Zamir A. A structurally novel transferrin-like protein accumulates in the plasma membrane of the unicellular green alga Dunaliella salina grown in high salinities. Journal of Biological Chemistry. 1997; 272:1565–1570.
21. Gomez PI, Gonzalez MA. Genetic polymorphism in eight Chilean strains of the carotenogenic microalga Dunaliella salina Teodoresco (Chlorophyta). Biological Research. 2001; 34:23–30.
22. Lichtenthaler HK, Wellburn AR. Determinations of total carotenoids and chlorophylls a and b of leaf extracts in different solvents. Biochemical Society Transactions. 1983; 11:591–592.
23. Schmittgen TD, Livak KJ. Analyzing real-time PCR data by the comparative CT method. Nature Protocols. 2008; 3:1101–1108.
24. Tavallaie S, Emtyazjoo M, Rostami K, Kosari H, Assadi M. Comparative studies of β-carotene and protein production from Dunaliella salina isolated from Lake Hoze-soltan, Iran. Journal of Aquatic Food Product Technology. 2015; 24:79–90.
25. Sharma P, Agarwal V, KrishnaMohan M, Kachhwaha S, Kothari SL. Isolation and characterization of Dunaliella species from Sambhar Lake (India) and its phylogenetic position in the genus Dunaliella using 18S rDNA. National Academy Science Letters. 2012; 35:207–213.
26. Nygard CA, Ekelund NG. Photosynthesis and UV-B tolerance of the marine alga Fucus vesiculosus at different sea water salinities. Journal of Applied Phycology. 2006; 18:461–467.
27. Ben-Amotz A, Avron M. Photosynthetic activities of the halophilic alga Dunaliella parva. Plant Physiology. 1972; 49:240–243.
28. Upasani V, Desai S. Sambhar Salt Lake: Chemical composition of the brines and studies on haloalkaliphilic archaebacteria. Archives of Microbiology. 1990; 154:589–593.
29. Abdullah Z, Ahmed R. Effect of pre and post kinetin treatment on salt tolerance of different potato cultivars growing on saline soils. Journal of Agronomy and Crop Science. 1990; 165:94–102.
30. Hamada AM, El-Enany AE. Effect of NaCl salinity on growth, pigment and mineral element contents, and gas exchange of broad bean and pea plants. Biologia Plantarum. 1994; 36:75–81.
31. Silva EN, Ribeiro RV, Ferreira-Silva SL, Viegas RA, Silveira JA. Comparative effects of salinity and water stress on photosynthesis, water relations and growth of Jatropha curcas plants. Journal of Arid Environments. 2010; 74:1130–1137.
32. Singh MP, Pandey SK, Singh M, Ram PC, Singh BB. Photosynthesis, transpiration, stomatal conductance and leaf chlorophyll content in mustard genotypes grown under sodic conditions. Photosynthetica. 1990; 24:623–627.
33. Misra AN, Sahu SM, Misra M, Singh P, Meera I, Das N, Kar M, Sahu P. Sodium chloride induced changes in leaf growth and pigment and protein contents in two rice cultivars. Biologia Plantarum. 1997; 39:257–262.
34. Lu CM, Vonshak A. Effects of salinity on photosystem II function in cyanobacterial Spirulina platensis cells. Physiologia Plantarum. 2002; 114:405–413.
35. Tang D, Shi S, Li D, Hu C, Liu Y. Physiological and biochemical responses of Scytonema javanicum (cyanobacterium) to salt stress. Journal of Arid Environments. 2007; 71:312–320.
36. Schubert H, Fulda S, Hagemann M. Effects of adaptation to different salt concentrations on photosynthesis and pigmentation of the cyanobacterium Synechocystis sp. PCC 6083. Journal of Plant Physiology. 1993; 142:291–295.
37. Johnson MK, Johnson EJ, Macelroy RD, Speer HL, Bruff SB. Effects of salts on the halophilic alga Dunaliella viridis. Journal of Bacteriology. 1968; 95: 1461–1468.
38. Kaiser WM, Heber U. Effect of high solute concentration on the permeability of the chloroplast envelope and on the activity of stroma enzyme. Planta. 1981; 153:423–429.
39. Spreitzer RJ, Salvucci ME. Rubisco: structure, regulatory interactions, and possibilities for a better enzyme. Annual Review of Plant Biology. 2002; 53:449–475.
40. Takabe T, Incharoensakdi A, Arakawa K, Yokota S. CO2 fixation rate and RuBisCO content increase in the halotolerant cyanobacterium, Aphanothece halophytica, grown in high salinities. Plant Physiology. 1988; 88:1120–1124.
41. Park S, Kim M, Lee S, Lee Y, Choi H, Jin E. Contrasting photoadaptive strategies of two morphologically distinct Dunaliella species under various salinities. Journal of Applied Phycology. 2015; 27:1053–1062.
42. Gilmour DJ, Hipkins MF, Boney AD. The effect of osmotic and ionic stress on the primary processes of photosynthesis in Dunaliella tertiolecta. Journal of Experimental Botany. 1984; 35:18–27.
43. Allakhverdiev SI, Sakamoto A, Nishiyama Y, Masami I, Murata N. Ionic and osmotic effects of NaCl-induced inactivation of photosystems I and II in Synechococcus sp. Plant Physiology. 2000; 123:1047–1056.
44. Misra AN, Sahu SM, Mishra M, Ramaswamy NK, Desai TS. Sodium chloride salt stress induced changes in thylakoid pigment-protein complexes, photosystem II activity and thermoluminescence glow peaks. Z Naturforsch. 1999; 54C:640–644.
45. Lu CM, Vonshak A. Characterization of PS II photochemistry in salt-adapted cells of cyanobacterium Spirulina platensis. New Phytologist. 1999; 141:231–239.
46. Satoh K, Smith CM, Fork DC. Effects of salinity on primary processes of photosynthesis in the red alga Porphyra perforata. Plant Physiology. 1983; 73:643–647.
47. Kim M, Park S, Polle JEW, Jin E. Gene expression profiling of Dunaliella sp. acclimated to different salinities. Phycological Research. 2010; 58:17–28.
48. Fisher M, Gokhman I, Pick U, Zamir A. A salt-resistant plasma membrane carbonic anhydrase is induced by salt in Dunaliella salina. Journal of Biological Chemistry. 1996; 271:17718–17723.
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