10.1371/journal.pgen.1006255
Shuo Zhou
Shuo
Zhou
Lixiu Jia
Lixiu
Jia
Hongye Chu
Hongye
Chu
Dan Wu
Dan
Wu
Xuan Peng
Xuan
Peng
Xu Liu
Xu
Liu
Jiaojiao Zhang
Jiaojiao
Zhang
Junfeng Zhao
Junfeng
Zhao
Kunming Chen
Kunming
Chen
Liqun Zhao
Liqun
Zhao
<i>Arabidopsis</i> CaM1 and CaM4 Promote Nitric Oxide Production and Salt Resistance by Inhibiting <i>S</i>-Nitrosoglutathione Reductase via Direct Binding
Public Library of Science
2016
salt-responsive CaM isoforms
GSNOR
protein-protein interaction assays
transcription-polymerase chain reaction analyses
AtCaM 4 expression
cam 4 plants
increase plant resistance
Arabidopsis CaM 1
AtCaM 1
AtCaM 4
CaM 4 Promote Nitric Oxide Production
plant salt resistance
plant resistance protein
4-GSNOR
salt tolerance
Direct Binding Salt
2016-09-29 17:30:01
Dataset
https://plos.figshare.com/articles/dataset/_i_Arabidopsis_i_CaM1_and_CaM4_Promote_Nitric_Oxide_Production_and_Salt_Resistance_by_Inhibiting_i_S_i_-Nitrosoglutathione_Reductase_via_Direct_Binding/3972657
<div><p>Salt is a major threat to plant growth and crop productivity. Calmodulin (CaM), the most important multifunctional Ca<sup>2+</sup> sensor protein in plants, mediates reactions against environmental stresses through target proteins; however, direct proof of the participation of CaM in salt tolerance and its corresponding signaling pathway <i>in vivo</i> is lacking. In this study, we found that <i>AtCaM1</i> and <i>AtCaM4</i> produced salt-responsive <i>CaM</i> isoforms according to real-time reverse transcription-polymerase chain reaction analyses; this result was verified based on a phenotypic analysis of salt-treated loss-of-function mutant and transgenic plants. We also found that the level of nitric oxide (NO), an important salt-responsive signaling molecule, varied in response to salt treatment depending on <i>AtCaM1</i> and <i>AtCaM4</i> expression. GSNOR is considered as an important and widely utilized regulatory component of NO homeostasis in plant resistance protein signaling networks. <i>In vivo</i> and <i>in vitro</i> protein-protein interaction assays revealed direct binding between AtCaM4 and <i>S</i>-nitrosoglutathione reductase (GSNOR), leading to reduced GSNOR activity and an increased NO level. Overexpression of <i>GSNOR</i> intensified the salt sensitivity of <i>cam4</i> mutant plants accompanied by a reduced internal NO level, whereas a <i>gsnor</i> deficiency increased the salt tolerance of <i>cam4</i> plants accompanied by an increased internal NO level. Physiological experiments showed that CaM4-GSNOR, acting through NO, reestablished the ion balance to increase plant resistance to salt stress. Together, these data suggest that AtCaM1 and AtCaM4 serve as signals in plant salt resistance by promoting NO accumulation through the binding and inhibition of GSNOR. This could be a conserved defensive signaling pathway in plants and animals.</p></div>