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The diversity of nitric oxide function in plant responses to metal stress

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Abstract

Nitric oxide (NO) emerges as signalling molecule, which is involved in diverse physiological processes in plants. High mobility metal interferes with NO signaling. The exogenous NO alleviates metal stress, whereas endogenous NO contributes to metal toxicity in plants. Owing to different cellular localization and concentration, NO may act as multifunctional regulator in plant responses to metal stress. It not only plays a crucial role in the regulation of gene expression, but serves as a long-distance signal. Through tight modulation of redox signaling, the integration among NO, reactive oxygen species and stress-related hormones in plants determines whether plants stimulate death pathway or activate survival signaling.

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Abbreviations

ABA:

Abscisic acid

ACO:

1-Aminocyclopropane-1-carboxylate oxidase

ACS:

1-Aminocyclopropane-1-carboxylate synthase

APX:

Ascorbate peroxidase

As:

Arsenic

BRs:

Brassinosteroids

CAT:

Catalase

Cu:

Copper

Cd:

Cadmium

cPTIO:

2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide

CTK:

Cytokinin

DAF-FM:

4-Amino-5-methylamino-2′,7′-difluorofluorescein

ET:

Ethylene

GSNOR1 :

S-Nitrosoglutathione reductase gene

Hsp71.2 :

Heat shock protein 71.2

JA:

Jasmonic acid

L-NMMA:

N G-Monomethyl-arginine monoacetate

MAPK:

Mitogen-activated protein kinase

MAT-1:

Met adenosyltransferases

Ni:

Nickel

NO:

Nitric oxide

NOS:

Nitric oxide synthase

NOX:

NADPH oxidase

NR:

Nitrate reductase

PA:

Polyamines

PAL:

Phenylalanine ammonialyase

PCD:

Programmed cell death

POX:

Peroxidase

PrP4A :

Pathogen-related proteins

ROS:

Reactive oxygen species

SAG12:

Senescence-associated gene 12

SNP:

Sodium nitroprusside

Zn:

Zinc

ZR:

Zeatin

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Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 30960181 and 31260296) and 2011 Guangxi Innovation Program for Graduates (GXU11T31076).

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He, H., He, L. & Gu, M. The diversity of nitric oxide function in plant responses to metal stress. Biometals 27, 219–228 (2014). https://doi.org/10.1007/s10534-014-9711-1

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