Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
INHIBITION OF ASCORBATE PEROXIDASE BY SALICYLIC-ACID AND 2,6-DICHLOROISONICOTINIC ACID, 2 INDUCERS OF PLANT DEFENSE RESPONSES
Autore:
DURNER J; KLESSIG DF;
Indirizzi:
RUTGERS STATE UNIV,WAKSMAN INST,POB 759 PISCATAWAY NJ 08855 RUTGERS STATE UNIV,WAKSMAN INST PISCATAWAY NJ 08855 RUTGERS STATE UNIV,DEPT MOLEC BIOL & BIOCHEM PISCATAWAY NJ 08855
Titolo Testata:
Proceedings of the National Academy of Sciences of the United Statesof America
fascicolo: 24, volume: 92, anno: 1995,
pagine: 11312 - 11316
SICI:
0027-8424(1995)92:24<11312:IOAPBS>2.0.ZU;2-0
Fonte:
ISI
Lingua:
ENG
Soggetto:
TOBACCO MOSAIC-VIRUS; SYSTEMIC ACQUIRED-RESISTANCE; SPINACH-CHLOROPLASTS; HYDROGEN-PEROXIDE; BINDING PROTEIN; KAPPA-B; INDUCTION; PURIFICATION; TRANSCRIPTION; LOCALIZATION;
Keywords:
REACTIVE OXYGEN SPECIES; ENHANCED DISEASE RESISTANCE; PATHOGENESIS-RELATED PROTEINS; PLANT SIGNAL TRANSDUCTION; HORSERADISH PEROXIDASE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
47
Recensione:
Indirizzi per estratti:
Citazione:
J. Durner e D.F. Klessig, "INHIBITION OF ASCORBATE PEROXIDASE BY SALICYLIC-ACID AND 2,6-DICHLOROISONICOTINIC ACID, 2 INDUCERS OF PLANT DEFENSE RESPONSES", Proceedings of the National Academy of Sciences of the United Statesof America, 92(24), 1995, pp. 11312-11316

Abstract

In recent years, it has become apparent that salicylic acid (SA) plays an important role in plant defense responses to pathogen attack. Previous studies have suggested that one of SA's mechanisms of action is the inhibition of catalase, resulting in elevated levels of H2O2, which activate defense-related genes. Here we demonstrate that SA also inhibits ascorbate peroxidase (APX), the other key enzyme for scavenging H2O2. The synthetic inducer of defense responses, 2,6-dichloroisonicotinic acid (INA), was also found to be an effective inhibitor of APS. In the presence of 750 mu M ascorbic acid (AsA), substrate-dependent IC50 values of 78 mu M and 95 mu M were obtained for SA and INA, respectively. Furthermore, the ability of SA analogues to block APX activity correlated with their ability to induce defense-related genes in tobacco and enhance resistance to tobacco mosaic virus. Inhibition of APX by Sri appears to be reversible, thus differing from the time-dependent, irreversible inactivation by suicide substrates such as p-aminophenol. In contrast to APX, the guaiacol-utilizing peroxidases, which participate in the synthesis and crosslinking of cell wall components as part of the defense response, are not inhibited by SA or INA. The inhibition of both catalase and APX, but not guaiacol peroxidases, supports the hypothesis that SA-induced defense responses are mediated, in part, through elevated H2O2 levels or coupled perturbations of the cellular redox state.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/03/20 alle ore 09:24:57