A role for the RNA-binding protein MOS2 in microRNA maturation in Arabidopsis.
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ABSTRACT:
SUBMITTER: Wu X
PROVIDER: S-EPMC3641593 | biostudies-literature | 2013 May
REPOSITORIES: biostudies-literature
Publications
A role for the RNA-binding protein MOS2 in microRNA maturation in Arabidopsis.
Wu Xueying X Shi Yupeng Y Li Jingrui J Xu Le L Fang Yuda Y Li Xin X Qi Yijun Y
Cell research 20130212 5
microRNAs (miRNAs) play important roles in the regulation of gene expression. In Arabidopsis, mature miRNAs are processed from primary miRNA transcripts (pri-miRNAs) by nuclear HYL1/SE/DCL1 complexes that form Dicing bodies (D-bodies). Here we report that an RNA-binding protein MOS2 binds to pri-miRNAs and is involved in efficient processing of pri-miRNAs. MOS2 does not interact with HYL1, SE, and DCL1 and is not localized in D-bodies. Interestingly, in the absence of MOS2, the recruitment of pr ...[more]
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Project description:microRNAs (miRNAs) play important roles in the regulation of gene expression. In Arabidopsis, mature miRNAs are processed from primary miRNA transcripts (pri-miRNAs) by nuclear HYL1/SE/DCL1 complexes that form Dicing bodies (D-bodies). Here we report that a RNA-binding protein MOS2 bound to pri-miRNAs and was required for their efficient processing. MOS2 did not interact with HYL1, SE, and DCL1 and was not localized in D-bodies. Interestingly, in the absence of MOS2, the recruitment of pri-miRNAs by HYL1 was greatly reduced and the localization of HYL1 in D-bodies was compromised. These data suggest that MOS2 facilitates pri-miRNA processing through facilitating the recruitment of pri-miRNAs by the Dicing complexes.
2012-10-27 | GSE41843 | GEO
Project description:microRNAs (miRNAs) play important roles in the regulation of gene expression. In Arabidopsis, mature miRNAs are processed from primary miRNA transcripts (pri-miRNAs) by nuclear HYL1/SE/DCL1 complexes that form Dicing bodies (D-bodies). Here we report that a RNA-binding protein MOS2 bound to pri-miRNAs and was required for their efficient processing. MOS2 did not interact with HYL1, SE, and DCL1 and was not localized in D-bodies. Interestingly, in the absence of MOS2, the recruitment of pri-miRNAs by HYL1 was greatly reduced and the localization of HYL1 in D-bodies was compromised. These data suggest that MOS2 facilitates pri-miRNA processing through facilitating the recruitment of pri-miRNAs by the Dicing complexes. Examination of gene expression profiles in Col-0 and mos2-2 plants by deep sequencing
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Project description:Posttranscriptional maturation is a critical step in microRNA (miRNA) biogenesis that determines mature miRNA levels. In addition to core components (Drosha and DGCR8 [DiGeorge syndrome critical region gene 8]) in the microprocessor, regulatory RNA-binding proteins may confer the specificity for recruiting and processing of individual primary miRNAs (pri-miRNAs). Here, we identify DDX1 as a regulatory protein that promotes the expression of a subset of miRNAs, including five members in the microRNA-200 (miR-200) family and four miRNAs in an eight-miRNA signature of a mesenchymal ovarian cancer subtype. A majority of DDX1-dependent miRNAs are induced after DNA damage. This induction is facilitated by the ataxia telangiectasia mutated (ATM)-mediated phosphorylation of DDX1. Inhibiting DDX1 promotes ovarian tumor growth and metastasis in a syngeneic mouse model. Analysis of The Cancer Genome Atlas (TCGA) reveals that low DDX1 levels are associated with poor clinical outcome in patients with serous ovarian cancer. These findings suggest that DDX1 is a key modulator in miRNA maturation and ovarian tumor suppression.
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