Small Grain and Dwarf 2, encoding an HD-Zip II family transcription factor, regulates plant development by modulating gibberellin biosynthesis in rice.
Plant Sci
; 288: 110208, 2019 Nov.
Article
em En
| MEDLINE
| ID: mdl-31521223
ABSTRACT
Homeodomain leucine zipper (HD-Zip) proteins are transcription factors that regulate plant development. Bioactive gibberellin (GA) is a key endogenous hormone that participates in plant growth. However, the relationship between HD-Zip genes and modulation of GA biosynthesis in rice remains elusive. Here, we identified a rice mutant, designated as small grain and dwarf 2 (sgd2), which had reduced height and grain size compared with the wild type. Cytological observations indicated that the defective phenotype was mainly due to decreased cell length. Map-based cloning and complementation tests demonstrated that a 9 bp deletion in a homeodomain leucine zipper (HD-Zip) II family transcription factor was responsible for the sgd2 mutant phenotype. Expression of SGD2 was pronounced in developing panicles, and its protein was localized in nucleus. Luciferase reporter system and transactivation assays in yeast suggested that SGD2 functioned as a transcriptional repressor. High performance liquid chromatography assays showed that the endogenous GA1 level in the sgd2 mutant was dramatically decreased, and exogenous GA3 recovered the second leaf sheath to normal length. Results of qRT-PCR showed that the expression levels of genes positively regulating GA-biosynthesis were mostly down-regulated in the mutant. Our data identified the role of an HD-Zip transcription factor that affects rice plant development by modulating gibberellin biosynthesis.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Reguladores de Crescimento de Plantas
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Proteínas de Plantas
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Oryza
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Fatores de Transcrição
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Giberelinas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Plant Sci
Ano de publicação:
2019
Tipo de documento:
Article