Modulation of Ethylene Responses Affects Plant Salt-Stress Responses

Abstract

Ethylene signaling plays important roles in multiple aspects of plant growth and development. Its functions in abiotic stress responses remain largely unknown. Here, we report that alteration of ethylene signaling affected plant salt-stress responses. A type II ethylene receptor homolog gene NTHK1 (Nicotiana tabacum histidine kinase 1) from tobacco (N. tabacum) conferred salt sensitivity in NTHK1-transgenic Arabidopsis (Arabidopsis thaliana) plants as judged from the phenotypic change, the relative electrolyte leakage, and the relative root growth under salt stress. Ethylene precursor 1-aminocyclopropane-1-carboxylic acid suppressed the salt-sensitive phenotype. Analysis of Arabidopsis ethylene receptor gain-of-function mutants further suggests that receptor function may lead to salt-sensitive responses. Mutation of EIN2, a central component in ethylene signaling, also results in salt sensitivity, suggesting that EIN2-mediated signaling is beneficial for plant salt tolerance. Overexpression of the NTHK1 gene or the receptor gain-of-function activated expression of salt-responsive genes AtERF4 and Cor6.6. In addition, the transgene NTHK1 mRNA was accumulated under salt stress, suggesting a posttranscriptional regulatory mechanism. These findings imply that ethylene signaling may be required for plant salt tolerance.

The Copper Transporter RAN1 Is Essential for Biogenesis of Ethylene Receptors in Arabidopsis

“…However, the subcellular localization of ETR1 and RAN1 when expressed in yeast remains to be determined. In Arabidopsis, ETR1 is an integral membrane protein located primarily in the membranes of the endoplasmic reticulum (45)(46)(47)(48)(49)(50)(51)(52). Although the subcellular location of RAN1 in Arabidopsis is unknown, our results suggest that it is co-localized in the same subcellular compartment with the receptors at some point during the biogenesis of the receptors in plants.…”

The mutual responses of higher plants to environment: Physiological and microbiological aspects

“…Plant secondary metabolism plays an important role in plant responding to environmental stresses. Long-step progress has taken place in terms of introducing transcriptional elements to regulate targeted pathways [93,95,108,136,141].…”

“…Plant production realization is obtained eventually through physiological pathways at least at the level of individual and community [102][103][104][105][106][107][108][109]120,[130][131][132][133][134][135][136][137][138][139][140]. One molecule or cell cannot produce any economic effect in field [22,23,77,78,117].…”

Probing the responses of four chicory ecotypes by ethylene accumulation and growth characteristics under drought stress

“…Ethylene is regarded as a stress hormone, because it is involved in many plant stress morphophysiological responses (Cao et al, 2007). Ethylene has an important role in many aspects of plant biology, from seed germination to dormancy, ripening and senescence, and the regulation of stomatal closure (by promoting NADPH oxidase-mediated reactive oxygen species (ROS) production in stomatal guard cells) as well as defences against biotic and abiotic stresses (Bartoli et al, 2013).…”

“…In several species, a significant increase in ethylene production has been reported under drought (Young et al, 2004) and salt stress (Wi and Park, 2002). Thus, identifying ethylene concentration is important in determining plant stress tolerance (Cao et al, 2007).…”