Sumoylation of the Plant Clock Transcription Factor CCA1 Suppresses DNA Binding.
J Biol Rhythms
; 32(6): 570-582, 2017 Dec.
Article
em En
| MEDLINE
| ID: mdl-29172852
ABSTRACT
In plants, the circadian clock regulates the expression of one-third of all transcripts and is crucial to virtually every aspect of metabolism and growth. We now establish sumoylation, a posttranslational protein modification, as a novel regulator of the key clock protein CCA1 in the model plant Arabidopsis. Dynamic sumoylation of CCA1 is observed in planta and confirmed in a heterologous expression system. To characterize how sumoylation might affect the activity of CCA1, we investigated the properties of CCA1 in a wild-type plant background in comparison with ots1 ots2, a mutant background showing increased overall levels of sumoylation. Neither the localization nor the stability of CCA1 was significantly affected. However, binding of CCA1 to a target promoter was significantly reduced in chromatin-immunoprecipitation experiments. In vitro experiments using recombinant protein revealed that reduced affinity to the cognate promoter element is a direct consequence of sumoylation of CCA1 that does not require any other factors. Combined, these results suggest sumoylation as a mechanism that tunes the DNA binding activity of the central plant clock transcription factor CCA1.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fatores de Transcrição
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Arabidopsis
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Proteínas de Arabidopsis
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Sumoilação
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article