Transgenic Expression of MsHsp23 Confers Enhanced Tolerance to Abiotic Stresses in Tall Fescue

Abstract

Tall fescue (Festuca arundinacea Schreb.) is an important cool season forage plant that is not well suited to extreme heat, salts, or heavy metals. To develop transgenic tall fescue plants with enhanced tolerance to abiotic stress, we introduced an alfalfa Hsp23 gene expression vector construct through Agrobacterium-mediated transformation. Integration and expression of the transgene were confirmed by polymerase chain reaction, northern blot, and western blot analyses. Under normal growth conditions, there was no significant difference in the growth of the transgenic plants and the non-transgenic controls. However, when exposed to various stresses such as salt or arsenic, transgenic plants showed a significantly lower accumulation of hydrogen peroxide and thiobarbituric acid reactive substances than control plants. The reduced accumulation of thiobarbituric acid reactive substances indicates that the transgenic plants possessed a more efficient reactive oxygen species-scavenging system. We speculate that the high levels of MsHsp23 proteins in the transgenic plants protect leaves from oxidative damage through chaperon and antioxidant activities. These results suggest that MsHsp23 confers abiotic stress tolerance in transgenic tall fescue and may be useful in developing stress tolerance in other crops.

Comparative Physiological and Molecular Analyses of Two Contrasting Flue-Cured Tobacco Genotypes under Progressive Drought Stress

“…Heat shock proteins (HSPs) 70 and 23 are two classes of chaperons, which could protect cells against damage caused by environmental stresses in plants. Overexpression of cytoplasmic HSP70-1 or mitochondrial HSP23 contributes to drought stress tolerance in transgenic tobacco (Cho and Hong, 2006 ; Lee et al, 2012 ). In this study, drought stress resulted in increased expression of HSP70-1 and HSP23 , and LJ851 showed significantly higher HSP70-1 and HSP23 expression in both leaves and roots compared to JX6007 under drought stress (Figures 8C,D ).…”

Comparative Physiological and Transcriptional Analyses of Two Contrasting Drought Tolerant Alfalfa Varieties

“…Heat shock proteins (HSPs) are critical for protecting cells against damage caused by environmental stresses in a wide range of organisms. Overexpression of alfalfa mitochondrial HSP23 confers enhanced tolerance to abiotic stress in transgenic tobacco and tall fescue ( Lee et al, 2012a , b ). The high levels of MsHSP23 proteins in the transgenic plants protect cells from oxidative damage through chaperon and antioxidant activities ( Lee et al, 2012b ).…”

“…Overexpression of alfalfa mitochondrial HSP23 confers enhanced tolerance to abiotic stress in transgenic tobacco and tall fescue ( Lee et al, 2012a , b ). The high levels of MsHSP23 proteins in the transgenic plants protect cells from oxidative damage through chaperon and antioxidant activities ( Lee et al, 2012b ). In this study, drought stress resulted in increased expression of MtHSP23 , and Longdong showed significantly higher MtHSP23 expression in both leaf and root compared to Algonquin under drought stress ( Figure 9H ).…”

Improving the Yield and Nutritional Quality of Forage Crops

“…Importantly these increases were shown both in the laboratory but also in field conditions. This study also identified the increased expression of many interesting genes, including M. sativa Heat Shock Protein23 ( HSP23 ), a gene already shown to enhance abiotic stress tolerance in both Nicotiana tabacum and Festuca ( Lee et al, 2012a , b ) along with other members of the MsHSP family ( Li et al, 2016 ; Li Z. et al, 2017 ). Similarly, for the Ethylene Response Factor ( ERF ) family studies have been shown that introducing the M. sativa gene into other plants can confer enhanced resistance to salinity; MsERF9 and MsERF11 in Nicotiana and Arabidopsis , respectively ( Chen et al, 2012a , b ).…”