Ectopic Overexpression of Barley PIP2;4 Confers Salt Tolerance in Arabidopsis

Jay Prakash Awasthi,Jayeeta Mitra,Sanjib Kumar Panda

doi:10.3126/ijasbt.v4i4.16254

Abstract

In the present study HvPIP2;4 was overexpressed in Arabidopsis thaliana to engineer enhanced salt tolerance. Barley Aquaporin was selected since barley shows fairly good tolerance to drought, salt stress and low temperature compared to many other crops including rice, and it was thought that analysis of barley aquaporin will provide a good insight into the molecular mechanisms involved in transport of water & their efficacy during abiotic stress condition. Arabidopsis line expressing HvPIP2;4 from annual crop plant Hordeum vulgare (Barley) under the control of constitutive promoter was used to analyze the expression of HvPIP2; 4 and its efficacy during salt stress when NaCl concentration gradually increased. The pattern of expression of HvPIP2; 4 were found to be NaCl dose dependent during salt stress. The constitutive expression of HvPIP2;4 enhanced salt stress tolerance in Arabidopsis. HvPIP2;4 played a dominant role in improving plant salt tolerance. It may be very well presumed that overexpression of HvPIP2;4 in crop plant might benefit them by enhancing their salt tolerance capacity.Int J Appl Sci Biotechnol, Vol 4(4): 498-512

Highlights

Water plays a very important role in plant growth and development, a fundamental requirement of the proper growth of plants is adequate uptake of water and its flow across the membrane (Agre and Homer, 2000)
Plant aquaporin was first discovered by Maurel et al, 1993 thereafter a large number of plant aquaporin has been reported from other plant species such as Arabidopsis 35, Tomato 47, Maize 36, Rice 33 and 71 in Cotton (Johanson et al, 2001; Chaumont et al, 2011; Sakurai et al, 2005; Park et al, 2010)
In various studies it was found that a rise in concentrations of salt has shown to inhibit root water uptake due to reduction in root hydraulic conductance and thereby increasing the transmembrane diffusion efficiency of water (Obroucheva et al, 2010)

Summary

Introduction

Water plays a very important role in plant growth and development, a fundamental requirement of the proper growth of plants is adequate uptake of water and its flow across the membrane (Agre and Homer, 2000). In various studies it was found that a rise in concentrations of salt has shown to inhibit root water uptake due to reduction in root hydraulic conductance and thereby increasing the transmembrane diffusion efficiency of water (Obroucheva et al, 2010). Several measures such as heterologous co expression in oocytes, interaction of proteins and their detection in mutant yeast, overexpression of certain genes in plants and inhibitors have been utilized to analyze the functionality of aquaporins. Salinity had affected about half of the world’s irrigated land and more than 20% of the cultivated land (Mahajan and Tuteja, 2005).To cope with the increasing food requirement minimization of losses incurred due to abiotic stress is a major concern for all

Methods

Results

Conclusion