Transcriptome map for seedling stage specific salinity stress response indicates a specific set of genes as candidate for saline tolerance in Oryza sativa L.
- 989 Downloads
Oryza sativa L. cv IR64 is a widely cultivated, salt-sensitive indica rice, while Pokkali is a well-known, naturally salt-tolerant relative. To understand the molecular basis of differences in their salinity tolerance, three subtractive cDNA libraries were constructed. A total of 1,194 salinity-regulated cDNAs are reported here that may serve as repositories for future individual gene-based functional genomics studies. Gene expression data using macroarrays and Northern blots gives support to our hypothesis that salinity tolerance of Pokkali may be due to constitutive overexpression of many genes that function in salinity tolerance and are stress inducible in IR64. Analysis of genome architecture revealed the presence of these genes on all the chromosomes with several distinct clusters. Notably, a few mapped on one of the major quantitative trait loci – Saltol – on chromosome 1 and were found to be differentially regulated in the two contrasting genotypes. The present study also defines a set of known abiotic stress inducible genes, including CaMBP, GST, LEA, V-ATPase, OSAP1 zinc finger protein, and transcription factor HBP1B, that were expressed at high levels in Pokkali even in the absence of stress. These proposed genes may prove useful as “candidates” in improving salinity tolerance in crop plants using transgenic approach.
KeywordsGenome Oryza sativa L. Salinity Transcriptome
This work was supported by research grants received from the International Atomic Energy Agency (Vienna), International Foundation for Science (Sweden), Department of Science and Technology, Department of Biotechnology, Government of India, and fellowship (S. K.) from the Council of Scientific and Industrial Research, Government of India.
- Bajji M, Kinet JM, Lutts S (2004) The use of the electrolyte leakage method for assessing cell membrane stability as a water stress tolerance test in durum wheat. J Plant Growth Regul 36:61–70Google Scholar
- Bonilla P, Dvorak J, Mackill D, Deal K, Gregorio G (2002) RFLP and SSLP mapping of salinity tolerance genes in chromosome 1 of rice (Oryza sativa L.) using recombinant inbred lines. Philipp J Agric Sci 85:68–76Google Scholar
- Chinnusamy V, Jagendorf A, Zhu JK (2005) Understanding and improving salt tolerance in plants. Crop Sci 45:437–448Google Scholar
- Das-Chatterjee A, Goswami L, Maitra S, Dastidar KG, Ray S, Majumder AL (2006) Introgression of a novel salt-tolerant L-myo-inositol 1-phosphate synthase from Porteresia coarctata (Roxb.) Tateoka (PcINO1) confers salt tolerance to evolutionary diverse organisms. FEBS Lett 580:3980–3988PubMedCrossRefGoogle Scholar
- Khush GS, Virk PS (2005) Selection criteria. In: Hardy B (ed) IR varieties and their impact. vol. 15. International Rice Research Institute, Los BonasGoogle Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual, ed 2. Cold Spring Harbour Laboratory Press, Cold Spring HarborGoogle Scholar
- Taji T, Seki M, Satou M, Sakurai T, Kobayashi M, Ishiyama K, Narusaka Y, Narusaka M, Zhu JK, Shinozaki K (2004) Comparative genomics in salt tolerance between Arabidopsis and Arabidopsis-related halophyte salt cress using Arabidopsis microarray. Plant Physiol 135:1697–1709PubMedCrossRefGoogle Scholar
- Wong CE, Li Y, Labbe A, Guevara D, Nuin P, Whitty B, Diaz C, Golding GB, Gray GR, Weretilnyk EA et al (2006) Transcriptional profiling implicates novel interactions between abiotic stress and hormonal responses in Thellungiella, a close relative of Arabidopsis. Plant Physiol 140:1437–1450PubMedCrossRefGoogle Scholar
- Yoshiba Y, Kiyosue T, Katagiri T, Ueda H, Mizoguchi T, Yamaguchi-Shinozaki K, Wada K, Harada Y, Shinozaki K (1995) Correlation between the induction of a gene for D1-Pyroline-5′-carboxylate synthase and the accumulation of proline in Arabidopsis thaliana under osmotic stress. Plant J 7:751–760PubMedCrossRefGoogle Scholar