Dataset Information

Defining Transcriptional Regulatory Mechanisms for Primary let-7 miRNAs.

ABSTRACT: The let-7 family of miRNAs have been shown to control developmental timing in organisms from C. elegans to humans; their function in several essential cell processes throughout development is also well conserved. Numerous studies have defined several steps of post-transcriptional regulation of let-7 production; from pri-miRNA through pre-miRNA, to the mature miRNA that targets endogenous mRNAs for degradation or translational inhibition. Less-well defined are modes of transcriptional regulation of the pri-miRNAs for let-7. let-7 pri-miRNAs are expressed in polycistronic fashion, in long transcripts newly annotated based on chromatin-associated RNA-sequencing. Upon differentiation, we found that some let-7 pri-miRNAs are regulated at the transcriptional level, while others appear to be constitutively transcribed. Using the Epigenetic Roadmap database, we further annotated regulatory elements of each polycistron identified putative promoters and enhancers. Probing these regulatory elements for transcription factor binding sites identified factors that regulate transcription of let-7 in both promoter and enhancer regions, and identified novel regulatory mechanisms for this important class of miRNAs.

SUBMITTER: Gaeta X

PROVIDER: S-EPMC5215532 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Defining Transcriptional Regulatory Mechanisms for Primary let-7 miRNAs.

Gaeta Xavier X Le Luat L Lin Ying Y Xie Yuan Y Lowry William E WE

PloS one 20170104 1

The let-7 family of miRNAs have been shown to control developmental timing in organisms from C. elegans to humans; their function in several essential cell processes throughout development is also well conserved. Numerous studies have defined several steps of post-transcriptional regulation of let-7 production; from pri-miRNA through pre-miRNA, to the mature miRNA that targets endogenous mRNAs for degradation or translational inhibition. Less-well defined are modes of transcriptional regulation ...[more]

PMID: 28052101

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Dataset Information

Defining Transcriptional Regulatory Mechanisms for Primary let-7 miRNAs.

Publications

Defining Transcriptional Regulatory Mechanisms for Primary let-7 miRNAs.

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