Salt-induced abnormalities on root tip mitotic cells of Allium cepa: prevention by inositol pretreatment
- 276 Downloads
Salt-induced growth reduction of plants is a well-known phenomenon which poses major problem in crop productivity in places where vast majority of land plants are affected by salt. In this report, studies were carried out to reveal the effect of salt injury on the cell division pattern in roots and the role of myo-inositol in preventing the salt-induced ion disequilibrium on the chromosome and DNA degradation in roots. Present study revealed induction of various chromosomal abnormalities on the root tip mitotic cells of Allium cepa by treatment with different concentrations of NaCl (0–500 mM) for 24 h as also the amelioration of such effect by prior treatment of the roots with different concentration of myo-inositol (0–300 mM). Results showed that a narrow albeit definite range of extracellular myo-inositol (100–150 mM) is effective in preventing internucleosomal fragmentation which is the early response in roots under salt stress. Transgenic tobacco plants overexpressing Oryza (OsINO1) as well as Porteresia (PcINO1) cytosolic l-myo-inositol-1-phosphate synthase coding genes can withstand and retain their chromosomal and DNA integrity in 100 mM NaCl solution and can subsequently prevent DNA fragmentation, caused by intracellular endonuclease activity at this salt concentration.
KeywordsSalt stress Cell division myo-Inositol Chromosomal abnormalities
The work has been supported by research grants (to ALM) from the Department of Biotechnology, Government of India.
Conflict of interest
The authors declare that they have no conflict of interest.
- Adams P, Thomas JC, Vernon DM, Bohnert HJ, Jensen RG (1992) Distinct cellular and organismic responses to salt stress. Plant Cell Physiol 33:1215–1223Google Scholar
- Das-Chatterjee A, Goswami L, Maitra S, Ghosh Dastidar K, Ray S, Majumder AL (2006) Introgression of a novel salt-tolerant L-myo-inositol l-phosphate synthase from Porteresia coarctata (Roxb.) Tateoka (PcINOl) confers salt tolerance to evolutionary diverse organisms. FEBS Letts 580:3980–3988Google Scholar
- DeWald DB, Torabinejad J, Jones CA, Shope J, Cangelosi AR, Thompson JE, Prestwich GD, Hama H (2001) Rapid accumulation of phosphatidylinositol 4, 5-bisphosphate and inositol 1, 4, 5-triphosphate correlates with calcium mobilization in salt stressed Arabidopsis. Plant Physiol 126:759–769CrossRefPubMedGoogle Scholar
- Katsuhara M (1997) Apoptosis-like cell death in barley roots under salt stress. Plant Cell Physiol 38:1091–1093Google Scholar
- Katsuhara M, Kawasaki T (1996) Salt stress induced nuclear and DNA degradation in meristematic cells of barley root. Plant Cell Physiol 37:169–173Google Scholar
- Loewus FA, Dickinson DB (1982) Cyclitols. In: Loewus FA, Tanner W (eds) Encyclopedia of plant physiology, new series, vol. 13A, plant carbohydrates. Springer, Berlin, pp 94–216Google Scholar
- Majee M, Maitra S, Dastidar KG, Pattnaik S, Chatterjee A, Hait NC, Das KP, Majumder AL (2004) A novel salt-tolerant L-myo-inositol-1-phosphate synthase from Porteresia coarctata (Roxb.) Tateoka, a halophytic wild rice, molecular cloning, bacterial overexpression, characterization, and functional introgression into tobacco conferring salt tolerance phenotype. J Biol Chem 279:28539–28552CrossRefPubMedGoogle Scholar