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C-Myc modulates microRNA processing via the transcriptional regulation of Drosha.

ABSTRACT: The c-Myc oncogenic transcription factor is known to regulate microRNA (miRNA) expression at the transcriptional level. However, little is known about the function of c-Myc in miRNA processing. Here, we report that Drosha, one of the most important components of the miRNA processing machinery, is a c-Myc target gene. c-Myc transactivates drosha mRNA expression, thus upregulating the Drosha protein level. A chromatin immunoprecipitation (ChIP) experiment revealed that c-Myc binds directly to the E-box of the drosha promoter. Both in vitro and in vivo microRNA processing assays demonstrated that c-Myc promotes miRNA processing by upregulating the Drosha expression level. Overall, our study reveals a previously unrecognised function of c-Myc in miRNA processing and provides valuable insight into a new aspect of how c-Myc regulates microRNA expression.

SUBMITTER: Wang X

PROVIDER: S-EPMC3672885 | biostudies-other | 2013

REPOSITORIES: biostudies-other

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c-Myc modulates microRNA processing via the transcriptional regulation of Drosha.

Wang Xingwu X Zhao Xiaocheng X Gao Ping P Wu Mian M

Scientific reports 20130101

The c-Myc oncogenic transcription factor is known to regulate microRNA (miRNA) expression at the transcriptional level. However, little is known about the function of c-Myc in miRNA processing. Here, we report that Drosha, one of the most important components of the miRNA processing machinery, is a c-Myc target gene. c-Myc transactivates drosha mRNA expression, thus upregulating the Drosha protein level. A chromatin immunoprecipitation (ChIP) experiment revealed that c-Myc binds directly to the ...[more]

PMID: 23735886

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