Dataset Information

Alu-miRNA interactions modulate transcript isoform diversity in stress response and reveal signatures of positive selection.

ABSTRACT: Primate-specific Alus harbor different regulatory features, including miRNA targets. In this study, we provide evidence for miRNA-mediated modulation of transcript isoform levels during heat-shock response through exaptation of Alu-miRNA sites in mature mRNA. We performed genome-wide expression profiling coupled with functional validation of miRNA target sites within exonized Alus, and analyzed conservation of these targets across primates. We observed that two miRNAs (miR-15a-3p and miR-302d-3p) elevated in stress response, target RAD1, GTSE1, NR2C1, FKBP9 and UBE2I exclusively within Alu. These genes map onto the p53 regulatory network. Ectopic overexpression of miR-15a-3p downregulates GTSE1 and RAD1 at the protein level and enhances cell survival. This Alu-mediated fine-tuning seems to be unique to humans as evident from the absence of orthologous sites in other primate lineages. We further analyzed signatures of selection on Alu-miRNA targets in the genome, using 1000 Genomes Phase-I data. We found that 198 out of 3177 Alu-exonized genes exhibit signatures of selection within Alu-miRNA sites, with 60 of them containing SNPs supported by multiple evidences (global-FST?>?0.3, pair-wise-FST?>?0.5, Fay-Wu's H??2.0, high ?DAF) and implicated in p53 network. We propose that by affecting multiple genes, Alu-miRNA interactions have the potential to facilitate population-level adaptations in response to environmental challenges.

SUBMITTER: Pandey R

PROVIDER: S-EPMC5009348 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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Alu-miRNA interactions modulate transcript isoform diversity in stress response and reveal signatures of positive selection.

Pandey Rajesh R Bhattacharya Aniket A Bhardwaj Vivek V Jha Vineet V Mandal Amit K AK Mukerji Mitali M

Scientific reports 20160902

Primate-specific Alus harbor different regulatory features, including miRNA targets. In this study, we provide evidence for miRNA-mediated modulation of transcript isoform levels during heat-shock response through exaptation of Alu-miRNA sites in mature mRNA. We performed genome-wide expression profiling coupled with functional validation of miRNA target sites within exonized Alus, and analyzed conservation of these targets across primates. We observed that two miRNAs (miR-15a-3p and miR-302d-3p ...[more]

PMID: 27586304

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Alu-miRNA interactions modulate transcript isoform diversity in stress response and reveal signatures of positive selection.

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Alu-miRNA interactions modulate transcript isoform diversity in stress response and reveal signatures of positive selection.

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