Stress-induced biphasic ethylene and ROS biosynthesis are synergistically interacted in cell damage

Abstract

Although reactive oxygen species (ROS) are inevitable by-products of many redox reactions in eukaryotic cells, they play a crucial role as signaling molecules in many cellular processes for development and defense response to abiotic stresses. The biphasic ROS production which was peaked twice in a first transient phase and a second massive phase was occurred after treatment of abiotic stress such as oxidative stress, high salinity. This biphasic generation of ROS was followed by the biphasic production of stress hormone, ethylene. The mechanism of interactions between ROS and ethylene biosynthesis is studied in tobacco (Nicotiana tabaccum L.) plants under the abiotic stresses. The stress-induced ethylene production was significantly inhibited in RbohD-AS and RbohF-AS, in which antisense expression of NADPH oxidase genes was performed. The accumulation of ROS, which was determined by DAB and DCFH-DA staining, was significantly decreased after abiotic stresses in transgenic plants. The suppression of signaling with ethylene and ROS induced more tolerance in response to abiotic stress. The transgenic plants were more tolerant in MS medium supplemented with salinity stress in contrast with wild-type. Stress-induced cell damage determined by DNA fragmentation was decreased at phase II in those transgenic plants. Therefore, the first burst of ROS is more responsible for making a role as a signaling molecule during stress-induced response. These results suggested that ethylene and ROS act in a positive feedback cycle that results in mutual enhancement of ethylene and ROS production during stress-induced cell death.

An NADPH-Oxidase/Polyamine Oxidase Feedback Loop Controls Oxidative Burst Under Salinity

“…The preparation of transgenic tobacco (Nicotiana tabacum 'Xanthi') plants with altered expression of the maize (Zea mays) POLYAMINE OXIDASE (ZmPAO) gene (lines A2 and S2.2) has been described previously (Moschou et al, 2008a(Moschou et al, , 2008b. The preparation of transgenic tobacco specifically downregulating the two genes coding NADPH oxidase, RbohD and RbohF, was described by Ji and Park (2011). Surface-sterilized transgenic seeds (T3 homozygous) were cultured on solid Murashige and Skoog medium (pH 5.8) and then transferred to soil under light (16/8-h photoperiod and 100 mmol photons m 22 s 21 ) at 25°C 6 5°C.…”

Synergistic Biosynthesis of Biphasic Ethylene and Reactive Oxygen Species in Response to HemibiotrophicPhytophthora parasiticain Tobacco Plants

“…Transgenic tobacco (Nicotiana tabacum 'Wisconsin 38') plants impaired in genes for ethylene synthesis or signaling and ROS generation (CAS-AS, CAO-AS, Ein3-AS, rbohD-as, and rbohF-as) were used in this study (Wi et al, 2010;Ji and Park, 2011). Surface-sterilized seeds were cultured on solid Murashige and Skoog medium (pH 5.8) under light (16L/8D, 50 mmol photons m 22 s 21 ) at room temperature (25°C 6 5°C).…”

Safety and Physicochemical Activities of Allium Hookeri

“…최근 우리나라는 영양과잉과 운동부족, 정신적 스트레스 증가 등으로 만성대사증후군이 급격히 증가하고 있는 실정이다 (Min et al, 2011;Ahn et al, 2016). 게다가 산업화로 증가된 각종 환 경오염 물질로 인해 생성된 reactive oxygen species (ROS)는 체 내에서 염증반응을 촉진시켜 노화와 만성질환 발생의 원인으로 작 용하여 (Hong, 2009;Ji & Park, 2011) 건강상의 위해를 가중시 키고 있다 (Choi & Kim, 2014). 이에 만성대사증후군을 예방하거 나 억제시키는데 도움이 되는 생리활성물질에 대한 연구가 활발히 진행되고 있다 (Masaki et al, 1995;Ham et al, 2017 (Yun et al, 2018) 대신 합성항산화제가 많이 사용되 었으나, 합성항산화제의 부작용이 차츰 밝혀지면서 안전한 천연 물에 대한 관심이 증가되고 있다 (Lee et al, 2008 (Ayam, 2011;Choe & Choe, 2014).…”