Inhibition of phosphoinositide-specific phospholipase C results in the induction of pathogenesis-related genes in soybean.
The inositol 1,4,5-trisphosphate (IP3) content is decreased in soybean cells following infection with Pseudomonas syringae pv. glycinea (Psg). In this investigation, a differential display approach was applied to isolate soybean genes that are transcriptionally up-regulated by the inhibition of phosphoinositide-specific phospholipase C (PI-PLC) activity and to study if the transcription of those genes is altered following Psg infection. Four genes, transcriptionally activated following treatment with the PI-PLC-specific inhibitor U-73122, were cloned. Three of the four genes were induced following infection with Psg. The transcripts of a hydrolase homologue (GmHy) were induced in the incompatible but not compatible soybean-Psg interaction. The transcripts of a putative ascorbate oxidase gene (GmAO) were induced in both compatible and incompatible interactions. GmHy and GmAO may represent new classes of pathogenesis-related genes. In addition to these two novel genes, homologues of PR-10 and polygalacturonase inhibitor protein (GmPR10 and GmPGIP, respectively) were identified. These two genes have previously been reported as pathogenesis-related. Transcripts of GmPR-10, but not GmPGIP, were induced in both compatible and incompatible soybean-Psg interactions. Induction of these genes, except for GmPGIP, following inhibition of PI-PLC by either the U-73122 treatment or bacterial infection suggests that PI-PLC may negatively regulate the expression of defence genes.
Chou
W-M
WM
Plant Biology Division, The Samuel Roberts Noble Foundation, P.O. Box 2180, Ardmore, Oklahoma 73402, USA.
Shigaki
T
T
Dammann
C
C
Liu
Y-Q
YQ
Bhattacharyya
M K
MK
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D043265:Phosphatidylinositol Diacylglycerol-Lyase / Q000037:antagonists & inhibitors*; D054801:Phosphoinositide Phospholipase C; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D013025:Glycine max / Q000235:genetics*; D014158:Transcription, Genetic
D010940:Plant Proteins; C053376:pathogenesis-related proteins, plant; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase