title: Arabidopsis nonsymbiotic hemoglobin AHb1 modulates nitric oxide bioactivity.
abstract: Nitric oxide (NO) is a widespread signaling molecule, and numerous targets of its action exist in plants. Whereas the activity of NO in erythrocytes, microorganisms, and invertebrates has been shown to be regulated by several hemoglobins, the function of plant hemoglobins in NO detoxification has not yet been elucidated. Here, we show that Arabidopsis thaliana nonsymbiotic hemoglobin AHb1 scavenges NO through production of S-nitrosohemoglobin and reduces NO emission under hypoxic stress, indicating its role in NO detoxification. However, AHb1 does not affect NO-mediated hypersensitive cell death in response to avirulent Pseudomonas syringae, suggesting that it is not involved in the removal of NO bursts originated from acute responses when NO mediates crucial defense signaling functions.
authors.affiliation: Dipartimento Scientifico e Tecnologico, Università degli Studi di Verona, 37134 Verona, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Perazzolli
authors.forename: Paola
authors.initials: P
authors.lastname: Dominici
authors.forename: Maria C
authors.initials: MC
authors.lastname: Romero-Puertas
authors.forename: Elisa
authors.initials: E
authors.lastname: Zago
authors.forename: Jürgen
authors.initials: J
authors.lastname: Zeier
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Sonoda
authors.forename: Chris
authors.initials: C
authors.lastname: Lamb
authors.forename: Massimo
authors.initials: M
authors.lastname: Delledonne
mesh_terms: D017360:Arabidopsis / Q000502:physiology; D029681:Arabidopsis Proteins / Q000502:physiology*; D001483:Base Sequence; D017931:DNA Primers; D006454:Hemoglobins / Q000502:physiology*; D047468:Immunoprecipitation; D009569:Nitric Oxide / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000502:physiology; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: C470347:AHB1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D017931:DNA Primers; D006454:Hemoglobins; D011994:Recombinant Proteins; D009569:Nitric Oxide