Dataset Information

The STAR protein QKI-7 recruits PAPD4 to regulate post-transcriptional polyadenylation of target mRNAs.

ABSTRACT: Emerging evidence has demonstrated that regulating the length of the poly(A) tail on an mRNA is an efficient means of controlling gene expression at the post-transcriptional level. In early development, transcription is silenced and gene expression is primarily regulated by cytoplasmic polyadenylation. In somatic cells, considerable progress has been made toward understanding the mechanisms of negative regulation by deadenylation. However, positive regulation through elongation of the poly(A) tail has not been widely studied due to the difficulty in distinguishing whether any observed increase in length is due to the synthesis of new mRNA, reduced deadenylation or cytoplasmic polyadenylation. Here, we overcame this barrier by developing a method for transcriptional pulse-chase analysis under conditions where deadenylases are suppressed. This strategy was used to show that a member of the Star family of RNA binding proteins, QKI, promotes polyadenylation when tethered to a reporter mRNA. Although multiple RNA binding proteins have been implicated in cytoplasmic polyadenylation during early development, previously only CPEB was known to function in this capacity in somatic cells. Importantly, we show that only the cytoplasmic isoform QKI-7 promotes poly(A) tail extension, and that it does so by recruiting the non-canonical poly(A) polymerase PAPD4 through its unique carboxyl-terminal region. We further show that QKI-7 specifically promotes polyadenylation and translation of three natural target mRNAs (hnRNPA1, p27(kip1)and ?-catenin) in a manner that is dependent on the QKI response element. An anti-mitogenic signal that induces cell cycle arrest at G1 phase elicits polyadenylation and translation of p27(kip1)mRNA via QKI and PAPD4. Taken together, our findings provide significant new insight into a general mechanism for positive regulation of gene expression by post-transcriptional polyadenylation in somatic cells.

SUBMITTER: Yamagishi R

PROVIDER: S-EPMC4824116 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The STAR protein QKI-7 recruits PAPD4 to regulate post-transcriptional polyadenylation of target mRNAs.

Yamagishi Ryota R Tsusaka Takeshi T Mitsunaga Hiroko H Maehata Takaharu T Hoshino Shin-ichi S

Nucleic acids research 20160229 6

Emerging evidence has demonstrated that regulating the length of the poly(A) tail on an mRNA is an efficient means of controlling gene expression at the post-transcriptional level. In early development, transcription is silenced and gene expression is primarily regulated by cytoplasmic polyadenylation. In somatic cells, considerable progress has been made toward understanding the mechanisms of negative regulation by deadenylation. However, positive regulation through elongation of the poly(A) ta ...[more]

PMID: 26926106

Similar Datasets

Project description:Background:Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide. microRNAs (miRNAs) repress gene expression by binding to complementary sequences in the 3' untranslated region (3'UTR) of target mRNAs. Alternative polyadenylation (APA) are relevant to the variability of the 3'UTR of mRNA. However, the posttranscriptional dysregulation of miRNAs and APA in CRC are poorly understood. Method:In this study, we conducted small RNA sequencing to identify differentially expressed miRNAs (DERs) and their target genes. Function analysis on DER-target genes can explain the regulation roles of miRNAs in CRC. The mutual regulation of miRNAs and APA was analyzed by combining miRNA data to 3'UTR alteration using 3' termini of polyadenylated RNAs sequencing (3T-seq) technique, and this was validated using TCGA gene expression data. Results:Our results showed 64 significant differentially expressed miRNAs (DERs) in CRC patients. Their target genes were related to cell adhesion and transcription regulation and were prevailingly involved in the CRC-related pathway. Integrative analysis of the miRNA and APA profile revealed 16 DERs were correlated with 12 polyadenylation factors, and six of them were significantly differently expressed in CRC. We also found four DERs that lost binding sites due to APA and showed a positive correlation between the miRNA and gene expression. Conclusion:Our study found that miRNAs regulated APA by modulating key polyadenylation factors, and several miRNAs lost their suppression on mRNA due to APA. Associating this with gene expression may provide some important clues for a deeper study of posttranscriptional cellular regulation and biomarker research in CRC. Our data provided the first evidence that the interaction between miRNAs and APA associated with gene expression could serve as biomarkers for CRC, suggesting that hsa-miR-133a-3p and MLEC, hsa-miR-145-5p and SET, hsa-miR-1-3p and PPIA, and hsa-miR-378d and YY1 might be novel and potential biomarkers in improving the diagnosis of CRC.

Dataset Information

The STAR protein QKI-7 recruits PAPD4 to regulate post-transcriptional polyadenylation of target mRNAs.

Publications

The STAR protein QKI-7 recruits PAPD4 to regulate post-transcriptional polyadenylation of target mRNAs.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure