A unique short-chain dehydrogenase/reductase in arabidopsis glucose signaling and abscisic acid biosynthesis and functions
Por:
Cheng W.-H., Endo A., Zhou L., Penney J., Chen H.-C., Arroyo A., Leon P., Nambara E., Asami T., Seo M., Koshiba T., Sheen J.
Publicada:
1 ene 2002
Resumen:
GIc has hormone-like functions and controls many vital processes through mostly unknown mechanisms in plants. We report here on the molecular cloning of GLUCOSE INSENSITIVE1 (GIN1) and ABSCISIC ACID DEFICIENT2 (ABA2) which encodes a unique Arabidopsis short-chain dehydrogenase/reductase (SDR1) that functions as a molecular link between nutrient signaling and plant hormone biosynthesis. SDR1 is related to SDR superfamily members involved in retinoid and steroid hormone biosynthesis in mammals and sex determination in maize. GIc antagonizes ethylene signal31ing by activating ABA2/GIN1 and other abscisic acid (ABA) biosynthesis and signaling genes, which requires GIc and ABA synergistically. Analyses of aba2/gin1 null mutants define dual functions of endogenous ABA in inhibiting the post-germination developmental switch modulated by distinct GIc and osmotic signals and in promoting organ and body size and fertility in the absence of severe stress. SDR1 is sufficient for the multistep conversion of plastid- and carotenoid-derived xanthoxin to abscisic aldehyde in the cytosol. The surprisingly restricted spatial and temporal expression of SDR1 suggests the dynamic mobilization of ABA precursors and/or ABA.
Filiaciones:
Cheng W.-H.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Endo A.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Zhou L.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Penney J.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Chen H.-C.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Arroyo A.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Leon P.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Nambara E.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Asami T.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Seo M.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Koshiba T.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
Sheen J.:
Department of Genetics, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, United States
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