Rice ASR1 Protein with Reactive Oxygen Species Scavenging and Chaperone-like Activities Enhances Acquired Tolerance to Abiotic Stresses in Saccharomyces cerevisiae

Abstract

Abscisic acid stress ripening (ASR1) protein is a small hydrophilic, low molecular weight, and stress-specific plant protein. The gene coding region of ASR1 protein, which is induced under high salinity in rice (Oryza sativa Ilmi), was cloned into a yeast expression vector pVTU260 and transformed into yeast cells. Heterologous expression of ASR1 protein in transgenic yeast cells improved tolerance to abiotic stresses including hydrogen peroxide (H 2 O 2 ), high salinity (NaCl), heat shock, menadione, copper sulfate, sulfuric acid, lactic acid, salicylic acid, and also high concentration of ethanol. In particular, the expression of metabolic enzymes (Fba1p, Pgk1p, Eno2p, Tpi1p, and Adh1p), antioxidant enzyme (Ahp1p), molecular chaperone (Ssb1p), and pyrimidine biosynthesis-related enzyme (Ura1p) was up-regulated in the transgenic yeast cells under oxidative stress when compared with wild-type cells. All of these enzymes contribute to an alleviated redox state to H 2 O 2 -induced oxidative stress. In the in vitro assay, the purified ASR1 protein was able to scavenge ROS by converting H 2 O 2 to H 2 O. Taken together, these results suggest that the ASR1 protein could function as an effective ROS scavenger and its expression could enhance acquired tolerance of ROS-induced oxidative stress through induction of various cell rescue proteins in yeast cells.

Saccharomyces cerevisiae KNU5377 Stress Response during High-Temperature Ethanol Fermentation

“…Spots with significant changes were considered accumulated proteins. Overexpressed spots of interest were excised from the gel and subjected to in-gel digestion and matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) (Kim et al, 2012). Finally, protein identification was conducted in MASCOT (http://www.matrixscience.com).…”

A Key Role for Apoplastic H2O2 in Norway Spruce Phenolic Metabolism

“…In tomato (Solanum lycopersicum), ASR1 has been found to act as a transcription factor also targeting cell wallrelated genes (Ricardi et al, 2014). In addition, rice (Oryza sativa) ASR1 may directly scavenge H 2 O 2 (Kim et al, 2012). Also, two putative TIFY genes were located in possible switch positions in the subnetwork ( Fig.…”

ASR1 transcription factor and its role in metabolism

“…20 In addition, these transgenic lines exhibit improved tolerance to oxidative stress by activating the antioxidant system. Moreover, rice ASR1 can scavenge ROS, 50 whereas soybean ASR1 buffers metal ions and thus provides antioxidant protection. 51 Therefore, ASR1 is probably involved in ROS depuration through several different mechanisms.…”