A subset of hypersensitive response marker genes, including HSR203J, is the downstream target of a spermine signal transduction pathway in tobacco.
A cellular signal transduction pathway induced by the polyamine, spermine (Spm), and transmitted by mitochondrial dysfunction is proposed in tobacco. In this investigation, we further resolve the pathway by identifying a subset of hypersensitive response (HR) marker genes as downstream components. In a previous report, we identified harpin-induced 1 (HIN1) and two closely related genes as responsive to Spm. Other HR marker genes, HSR203J, HMGR, HSR201, and HSR515, are also Spm-responsive. Induction of these HR marker genes, including HIN1, by Spm was suppressed by pre-treatment with antioxidants, calcium channel blockers, inhibitor of mitochondrial permeability transition pore openings, and blockers of amine oxidase/polyamine oxidase. Such quenching is also observed for Spm-induced activation of two mitogen-activated protein kinases (MAPKs), salicylic acid-induced protein kinase (SIPK), and wound-induced protein kinase (WIPK), and upregulation of the WIPK gene, suggesting that all these components are part of the same signaling pathway. Furthermore, gain-of-function and loss-of-function studies on MAPK cascade members reveal that the expression of Spm-induced HR marker genes varies with respect to involvement of SIPK/WIPK activation.
Takahashi
Yoshihiro
Y
Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577, Japan.
Uehara
Yukiko
Y
Berberich
Thomas
T
Ito
Akiko
A
Saitoh
Hiromasa
H
Miyazaki
Atsushi
A
Terauchi
Ryohei
R
Kusano
Tomonobu
T
D000975:Antioxidants / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004950:Esterases / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000378:metabolism*; D015398:Signal Transduction; D013096:Spermine / Q000502:physiology*; D014026:Nicotiana / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
D000975:Antioxidants; D002121:Calcium Channel Blockers; D010940:Plant Proteins; D013096:Spermine; D004950:Esterases; C088007:hsr203J protein, Nicotiana tabacum