Cellular mechanisms to survive salt in the halophyte Cakile maritima. (July 2018)

• Record Type: Journal Article
• Authors: Arbelet-Bonnin, Delphine; Ben Hamed-Laouti, Ibtissem; Laurenti, Patrick; Abdelly, Chedly; Ben Hamed, Karim; Bouteau, François
• Is Part Of: Plant science. Volume 272(2018)
• Page Start: 173
• Page End: 178
• Publication Date: 2018-07
• Subjects: Cakile maritima -- Halophyte -- Reactive oxygen species -- SOS -- Salt stress; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2018.04.018
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Cakile maritima is a putative crop and model of obligate halophyte. Two pathways could be induced by salt stress in C. maritima cultured cells. A first one dependent on superoxide generation and NSCC activation leads to PCD. A second one dependent on early singlet oxygen generation and Ca2 + influx allows the activation of H + -ATPases and a SOS-like system. This 2nd pathways allows cell repolarization, exclusion of Na + and survival. Abstract: We recently identified two behaviours in cultured cells of the salt accumulating halophyte Cakile maritima : one related to a sustained depolarization due to Na + influx through the non-selective cation channels leading to programmed cell death of these cells, a second one related to a transient depolarization allowing cells to survive (Ben Hamed-Laouti, 2016). In this study, we considered at the cellular level mechanisms that could participate to the exclusion of Na + out of the cell and thus participate in the regulation of the internal contents of Na + and cell survival. Upon addition of NaCl in the culture medium of suspension cells of C. maritima, we observed a rapid influx of Na + followed by an efflux dependent of the activity of plasma membrane H + -ATPases, in accordance with the functioning of a Na + /H + antiporter and the ability of some cells to repolarize. The Na + efflux was shown to be dependent on Na + -dependent on Ca 2+ influx like the SOS1 Na + /H + antiporter. We further could observe in response to salt addition, an early production of singlet oxygen ( 1 O2 ) probably due to peroxidase activities. This early 1 O2 production seemed to be a prerequisite to the Na + efflux. Our findings suggest that in addition to the pathway leading to PCD (Ben Hamed-Laouti, 2016), a second pathway comprising an SOS-like system could participate to the survival of a part of the C. maritima cultured cells challenged by salt stress.