Allene Oxide Cyclase from Camptotheca acuminata Improves Tolerance Against Low Temperature and Salt Stress in Tobacco and Bacteria

Abstract

Allene oxide cyclase (AOC, E 5.3.99.6) is an essential enzyme in jasmonate (JA) biosynthetic pathway. An AOC gene (defined as CaAOC, Database Accession No. AY863428) had been isolated from Camptotheca acuminata in previous work. Real-time quantitative PCR analysis indicated that mRNA expression of CaAOC was induced by salt stress (120 mM NaCl) and low temperature (4 degrees C). In order to further investigate the role of AOC gene in the processes, CaAOC was introduced into tobacco via Agrobacterium tumefaciens, and the transgenic lines were subjected to the examination of tolerance against salt stress and low temperature. Under salt stress, the chlorophyll content in transgenic tobacco was higher than that of in the wild plants. The electrolyte leakage test revealed that transgenic tobacco plants were more resistant to low temperature over control. Furthermore, 5'-truncated CaAOC was inserted into pET30 and then expressed in Escherichia coli strain BL21DE3 (pLysS). Interestingly, the transformants could grow on 2YT agar containing 400 mM NaCl. Although these mechanisms are not clear yet, this study suggested that CaAOC could not only be a potential target gene in the engineering of plants and bacteria for improved endurance against salt stress, but also be quite useful in enhancing plant tolerance to cold.

The Histone Deacetylase Inhibitor Suberoylanilide Hydroxamic Acid Alleviates Salinity Stress in Cassava

“…SAHA treatment enhanced MeAOC4 expression to 32.8-fold compared with untreated plants (Figure 7A). Previous studies have revealed that overexpression of AOCs can confer salinity stress tolerance to several crops (Yamada et al, 2002; Pi et al, 2009; Zhao et al, 2014). According to the current cassava genome database, AOCs constitute a small gene family ( MeAOC3-1 : RknMes02_049533: cassava4.1_014582m; MeAOC3-2 : RknMes02_054684: cassava4.1_026961m; and MeAOC4 : RknMes02_051874: cassava4.1_022180m) in cassava (Figure S1).…”

A Wheat Allene Oxide Cyclase Gene Enhances Salinity Tolerance via Jasmonate Signaling

“…[See online article for color version of this figure. ] sexangula) or a Camptotheca acuminate AOC in tobacco (Nicotiana tabacum) cells (Yamada et al, 2002;Pi et al, 2009). It is also well established that exposure to JA can improve the salinity tolerance of a number of plant species (Walia et al, 2007;del Amor and CuadraCrespo, 2011;Ismail et al, 2012).…”

Improvement of copper tolerance of Arabidopsis by transgenic expression of an allene oxide cyclase gene, GhAOC1, in upland cotton (Gossypium hirsutum L.)

“…AOC genes have been cloned from several plant species, including tomato [7], mangrove [8], Arabidopsis thaliana [9], barley [10], barrel medic [11], Hyoscyamus niger [12], Camptotheca acuminate [13], Jatropha curcas [14], Physcomitrella patens [15], Glycine max [6], and Leymus mollis [16]. Characterization of these genes from different plants has provided valuable information about their biochemical and physiological roles in adaptation to a variety of biotic and abiotic stresses.…”

“…For example, overexpression of JcAOC in Escherichia coli conferred resistance to salt stress and low temperature [14]. Ectopic overexpression of an AOC gene cloned from C. acuminate using the viral 35S promoter improved tolerance against salt stress and low temperature in transgenic tobacco plants compared to wild-type controls [13]. GmAOC5 transgenic tobaccos showed enhanced tolerance to oxidative stresses, while GmAOC1-expressing transgenic lines showed enhanced salinity stress tolerance [6].…”