Regulation of pri-miRNA processing by the hnRNP-like protein AtGRP7 in Arabidopsis.
Nucleic Acids Res
; 42(15): 9925-36, 2014 Sep.
Article
em En
| MEDLINE
| ID: mdl-25104024
ABSTRACT
The hnRNP-like glycine-rich RNA-binding protein AtGRP7 regulates pre-mRNA splicing in Arabidopsis. Here we used small RNA-seq to show that AtGRP7 also affects the miRNA inventory. AtGRP7 overexpression caused a significant reduction in the level of 30 miRNAs and an increase for 14 miRNAs with a minimum log2 fold change of ± 0.5. Overaccumulation of several pri-miRNAs including pri-miR398b, pri-miR398c, pri-miR172b, pri-miR159a and pri-miR390 at the expense of the mature miRNAs suggested that AtGRP7 affects pri-miRNA processing. Indeed, RNA immunoprecipitation revealed that AtGRP7 interacts with these pri-miRNAs in vivo. Mutation of an arginine in the RNA recognition motif abrogated in vivo binding and the effect on miRNA and pri-miRNA levels, indicating that AtGRP7 inhibits processing of these pri-miRNAs by direct binding. In contrast, pri-miRNAs of selected miRNAs that were elevated or not changed in response to high AtGRP7 levels were not bound in vivo. Reduced accumulation of miR390, an initiator of trans-acting small interfering RNA (ta-siRNA) formation, also led to lower TAS3 ta-siRNA levels and increased mRNA expression of the target AUXIN RESPONSE FACTOR4. Furthermore, AtGRP7 affected splicing of pri-miR172b and pri-miR162a. Thus, AtGRP7 is an hnRNP-like protein with a role in processing of pri-miRNAs in addition to its role in pre-mRNA splicing.
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Processamento Pós-Transcricional do RNA
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Proteínas de Ligação a RNA
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Arabidopsis
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Regulação da Expressão Gênica de Plantas
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Proteínas de Arabidopsis
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MicroRNAs
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article