MicroRNA (miRNA) biogenesis proceeds from a primary transcript (pri-miRNA) through the pre-miRNA into the mature miRNA. Here, we identify a role of the Caenorhabditis elegans nuclear export receptor XPO-1 and the cap-binding proteins CBP-20/NCBP-2 and CBP-80/NCBP-1 in this process. The RNA-mediated interference of any of these genes causes retarded heterochronic phenotypes similar to those obse...

BACKGROUND Because of the central functions of the mitochondria in providing metabolic energy and initiating apoptosis on one hand and the role that microRNA (miRNA) play in gene expression, we hypothesized that some miRNA could be present in the mitochondria for post-transcriptomic regulation by RNA interference. We intend to identify miRNA localized in the mitochondria isolated from human ske...

MicroRNAs (miRNAs) are small, non-coding RNA molecules encoded in the genomes, with length in range of 18-25 nucleotides. These molecules are transcribed from hairpin-loop primary ribonucleotides (pri-miRNA) by RNA polymerase II [1,2]. Pri-miRNAs are processed by RNase-III family enzyme, Dorsha, and then become 70nt precursor miRNA (pre-miRNA). The pre-miRNA is exported out to the cytoplasm by ...

MicroRNAs (miRNAs) are initially expressed as long transcripts that are processed in the nucleus to yield approximately 65-nucleotide (nt) RNA hairpin intermediates, termed pre-miRNAs, that are exported to the cytoplasm for additional processing to yield mature, approximately 22-nt miRNAs. Here, we demonstrate that human pre-miRNA nuclear export, and miRNA function, are dependent on Exportin-5....

microRNAs (miRNAs) are single-stranded, 21- to 23-nucleotide cellular RNAs that control the expression of cognate target genes. Primary miRNA (pri-miRNA) transcripts are transformed to mature miRNA by the successive actions of two RNase III endonucleases. Drosha converts pri-miRNA transcripts to precursor miRNA (pre-miRNA); Dicer, in turn, converts pre-miRNA to mature miRNA. Here, we show that ...

BACKGROUND Sarcomas consist of both tumor and stromal cells, and the interaction between these compartments is critical for tumor progression and metastasis. Tumor-derived factors may alter the differentiation capacity of the adjacent stromal cells. The aim of this study was to elucidate the paracrine impact of liposarcoma cells on pre-adipocytes, their adipogenic differentiation process and mi...

BACKGROUND It is generally believed that the miRNA processing machinery ensures the generation of a mature miRNA with a fixed sequence, particularly at its 5' end. However, we and others have recently noted that the ends of a given mature miRNA are not absolutely fixed, but subject to variation. Neither the significance nor the mechanism behind the generation of such miRNA polymorphism is under...

MicroRNAs (miRNAs) are short single-stranded RNA molecules that regulate gene expression. MiRNAs originate from large primary (pri) and precursor (pre) transcripts that undergo various processing steps along their biogenesis pathway till they reach their mature and functional form. It is not clear, however, whether all miRNAs are processed similarly. Here we show that the ratio between pre-miRN...

MicroRNAs (miRNAs) play a major role in the post-transcriptional regulation of target genes, especially in development and differentiation. Our understanding about the transcriptional regulation of miRNA genes is limited by inadequate annotation of primary miRNA (pri-miRNA) transcripts. Here, we used CAGE-seq and RNA-seq to provide genome-wide identification of the pri-miRNA core promoter reper...