Arabidopsis nonsymbiotic hemoglobin AHb1 modulates nitric oxide bioactivity.
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.
Perazzolli
Michele
M
Dipartimento Scientifico e Tecnologico, Università degli Studi di Verona, 37134 Verona, Italy.
Dominici
Paola
P
Romero-Puertas
Maria C
MC
Zago
Elisa
E
Zeier
Jürgen
J
Sonoda
Masatoshi
M
Lamb
Chris
C
Delledonne
Massimo
M
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
C470347:AHB1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D017931:DNA Primers; D006454:Hemoglobins; D011994:Recombinant Proteins; D009569:Nitric Oxide