NSF Org:	IOS Division Of Integrative Organismal Systems
Recipient:	UNIVERSITY OF FLORIDA
Initial Amendment Date:	April 12, 2001
Latest Amendment Date:	September 4, 2001
Award Number:	0091064
Award Instrument:	Standard Grant
Program Manager:	Steve R. Rodermel IOS  Division Of Integrative Organismal Systems BIO  Directorate for Biological Sciences
Start Date:	April 15, 2001
End Date:	December 31, 2004 (Estimated)
Total Intended Award Amount:	$356,041.00
Total Awarded Amount to Date:	$364,141.00
Funds Obligated to Date:	FY 2001 = $364,141.00
History of Investigator:	Harry Klee (Principal Investigator) hjklee@ifas.ufl.edu Jeffrey Jones (Co-Principal Investigator)
Recipient Sponsored Research Office:	University of Florida 1523 UNION RD RM 207 GAINESVILLE FL  US  32611-1941 (352)392-3516
Sponsor Congressional District:	03
Primary Place of Performance:	University of Florida 1523 UNION RD RM 207 GAINESVILLE FL  US  32611-1941
Primary Place of Performance Congressional District:	03
Unique Entity Identifier (UEI):	NNFQH1JAPEP3
Parent UEI:
NSF Program(s):	INTEGRATIVE PLANT BIOLOGY
Primary Program Source:	01000102DB NSF RESEARCH & RELATED ACTIVIT
Program Reference Code(s):	9109, 9178, BIOT
Program Element Code(s):	114500
Award Agency Code:	4900
Fund Agency Code:	4900
Assistance Listing Number(s):	47.074

ABSTRACT


The interactions of plants and disease-causing pathogens generally fall into two types: compatible and incompatible. Incompatibility leads to resistance while compatibility leads to disease. In the absence of a resistant response, disease symptoms can spread, leading to severe damage or death of the plant. Analysis of mutants unable to synthesize ethylene, salicylic acid (SA) or jasmonic acid (JA), defined a multistage sequence of disease symptom development during a compatible tomato:pathogen interaction. Synthesis of all three phytohormones is essential for complete symptom development. The spread of disease is associated with an ethylene-dependent accumulation of SA. The position of JA within this cascade of events has yet to be determined. We intend to elucidate how these three hormones control symptom development. Experiments will define at a molecular genetic level the roles of ethylene, SA and JA in symptom development in tomato. Through a combination of hormone quantitation and add-backs, the order of action of the three hormones relative to one another will be determined. Microarray analyses will be performed to identify components of the progression from infection to cell death. These experiments will be complemented by work involving Arabidopsis:Xanthomonas interactions. In Arabidopsis, there is differential attenuation of disease symptoms with ethylene insensitive mutants in the various hormone receptors. This result suggests distinct functions for the five ethylene receptors. Molecular and genetic approaches will be used to define the differential responses. These experiments have the potential to identify unique functions for what has heretofore been considered a redundant receptor family.

Please report errors in award information by writing to: awardsearch@nsf.gov.