Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.


Logo for

PLANT CELL 16 (10): 2809-2821

Copyright © 2004 by the American Society of Plant Physiologists.

A Patch of Surface-Exposed Residues Mediates Negative Regulation of Immune Signaling by Tomato Pto Kinase{boxw}

Ai-Jiuan Wua, Vasilios M.E. Andriotisa, Marcus C. Durrantb, and John P. Rathjena,1

a Sainsbury Laboratory, Norwich Research Park, Norwich, Norfolk, NR4 7UH, United Kingdom
b Computational Biology Group, John Innes Centre, Norwich, Norfolk, NR4 7UH, United Kingdom

1 To whom correspondence should be addressed. E-mail john.rathjen{at}; fax 44-1603-450-011.

Abstract: Tomato (Lycopersicon esculentum) Pto kinase specifically recognizes the Pseudomonas effector proteins AvrPto and AvrPtoB, leading to induction of defense responses and hypersensitive cell death. Structural modeling of Pto combined with site-directed mutagenesis identified a patch of surface-exposed residues required for native regulation of signaling. Mutations in this area resulted in constitutive gain-of-function (CGF) forms of Pto that activated AvrPto-independent cell death via the cognate signaling pathway. The patch overlaps the peptide binding region of the kinase catalytic cleft and is part of a broader region required for interaction with bacterial effectors. We propose that the negative regulatory patch is normally occupied by a peptide that represses Pto signaling. Furthermore, we found that Pto kinase activity was required for Avr-dependent activation but dispensable for signaling by CGF forms of Pto. This suggests that Pto signals by a conformational change rather than phosphorylation of downstream substrates in the defense signaling pathway.

Identification of Arabidopsis VTC3 as a putative and unique dual function protein kinase::protein phosphatase involved in the regulation of the ascorbic acid pool in plants.
P. L. Conklin, D. DePaolo, B. Wintle, C. Schatz, and G. Buckenmeyer (2013)
J. Exp. Bot. 64, 2793-2804
   Abstract »    Full Text »    PDF »
Plant Programmed Cell Death Caused by an Autoactive Form of Prf Is Suppressed by Co-Expression of the Prf LRR Domain.
X. Du, M. Miao, X. Ma, Y. Liu, J. C. Kuhl, G. B. Martin, and F. Xiao (2012)
Mol Plant 5, 1058-1067
   Abstract »    Full Text »    PDF »
Proteolysis of a Negative Regulator of Innate Immunity Is Dependent on Resistance Genes in Tomato and Nicotiana benthamiana and Induced by Multiple Bacterial Effectors.
Y. Luo, K. S. Caldwell, T. Wroblewski, M. E. Wright, and R. W. Michelmore (2009)
PLANT CELL 21, 2458-2472
   Abstract »    Full Text »    PDF »
Crystal Structure of the Complex between Pseudomonas Effector AvrPtoB and the Tomato Pto Kinase Reveals Both a Shared and a Unique Interface Compared with AvrPto-Pto.
J. Dong, F. Xiao, F. Fan, L. Gu, H. Cang, G. B. Martin, and J. Chai (2009)
PLANT CELL 21, 1846-1859
   Abstract »    Full Text »    PDF »
Bypassing Kinase Activity of the Tomato Pto Resistance Protein with Small Molecule Ligands.
D. Salomon, A. Bonshtien, M. Mayrose, C. Zhang, K. M. Shokat, and G. Sessa (2009)
J. Biol. Chem. 284, 15289-15298
   Abstract »    Full Text »    PDF »
Host Inhibition of a Bacterial Virulence Effector Triggers Immunity to Infection.
V. Ntoukakis, T. S. Mucyn, S. Gimenez-Ibanez, H. C. Chapman, J. R. Gutierrez, A. L. Balmuth, A. M. E. Jones, and J. P. Rathjen (2009)
Science 324, 784-787
   Abstract »    Full Text »    PDF »
Natural Variation in the Pto Disease Resistance Gene Within Species of Wild Tomato (Lycopersicon). II. Population Genetics of Pto.
L. E. Rose, R. W. Michelmore, and C. H. Langley (2007)
Genetics 175, 1307-1319
   Abstract »    Full Text »    PDF »
The Absence of Histone H2B Monoubiquitination in the Arabidopsis hub1 (rdo4) Mutant Reveals a Role for Chromatin Remodeling in Seed Dormancy.
Y. Liu, M. Koornneef, and W. J.J. Soppe (2007)
PLANT CELL 19, 433-444
   Abstract »    Full Text »    PDF »
The Tomato NBARC-LRR Protein Prf Interacts with Pto Kinase in Vivo to Regulate Specific Plant Immunity.
T. S. Mucyn, A. Clemente, V. M.E. Andriotis, A. L. Balmuth, G. E.D. Oldroyd, B. J. Staskawicz, and J. P. Rathjen (2006)
PLANT CELL 18, 2792-2806
   Abstract »    Full Text »    PDF »
The Pto Kinase of Tomato, Which Regulates Plant Immunity, Is Repressed by Its Myristoylated N Terminus.
V. M. E. Andriotis and J. P. Rathjen (2006)
J. Biol. Chem. 281, 26578-26586
   Abstract »    Full Text »    PDF »
Natural Variation in the Pto Pathogen Resistance Gene Within Species of Wild Tomato (Lycopersicon). I. Functional Analysis of Pto Alleles.
L. E. Rose, C. H. Langley, A. J. Bernal, and R. W. Michelmore (2005)
Genetics 171, 345-357
   Abstract »    Full Text »    PDF »
Regulation of Plant Symbiosis Receptor Kinase through Serine and Threonine Phosphorylation.
S. Yoshida and M. Parniske (2005)
J. Biol. Chem. 280, 9203-9209
   Abstract »    Full Text »    PDF »
Mechanism of Pto-Mediated Disease Resistance: Structural Analysis Provides a New Model.
N. A. Eckardt (2004)
PLANT CELL 16, 2543-2545
   Full Text »    PDF »

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882