Processing of primary microRNAs by the microprocessor complex

• Published in: Nature 2004-11, Vol.432 (7014), p.231-235
• Main Authors: Denli, A.M, Tops, B.B.J, Plasterk, R.H.A, Ketting, R.F, Hannon, G.J
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Caenorhabditis elegans; Caenorhabditis elegans - genetics; Caenorhabditis elegans - metabolism; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Cell Line; double-stranded RNA; Drosophila; Drosophila melanogaster; Drosophila melanogaster - genetics; Drosophila melanogaster - metabolism; Drosophila Proteins - chemistry; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Endoribonucleases - genetics; Endoribonucleases - metabolism; Fundamental and applied biological sciences. Psychology; Gene expression; gene expression regulation; Genes, Reporter - genetics; Humanities and Social Sciences; Humans; Insects; letter; Microbiology; MicroRNAs - genetics; MicroRNAs - metabolism; Molecular and cellular biology; Molecular genetics; multidisciplinary; Multiprotein Complexes; Phenotype; Protein Binding; Protein Structure, Tertiary; Proteins; Ribonuclease III - chemistry; Ribonuclease III - genetics; Ribonuclease III - metabolism; ribonucleases; Ribonucleic acid; RNA; RNA Processing, Post-Transcriptional; RNA-binding proteins; RNA-Binding Proteins - chemistry; RNA-Binding Proteins - metabolism; Science; Science (multidisciplinary)
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/nature03049

Mature microRNAs (miRNAs) are generated via a two-step processing pathway to yield approximately 22-nucleotide small RNAs that regulate gene expression at the post-transcriptional level. Initial cleavage is catalysed by Drosha, a nuclease of the RNase III family, which acts on primary miRNA transcripts (pri-miRNAs) in the nucleus. Here we show that Drosha exists in a multiprotein complex, the Microprocessor, and begin the process of deconstructing that complex into its constituent components. Along with Drosha, the Microprocessor also contains Pasha (partner of Drosha), a double-stranded RNA binding protein. Suppression of Pasha expression in Drosophila cells or Caenorhabditis elegans interferes with pri-miRNA processing, leading to an accumulation of pri-miRNAs and a reduction in mature miRNAs. Finally, depletion or mutation of pash-1 in C. elegans causes de-repression of a let-7 reporter and the appearance of phenotypic defects overlapping those observed upon examination of worms with lesions in Dicer (dcr-1) or Drosha (drsh-1). Considered together, these results indicate a role for Pasha in miRNA maturation and miRNA-mediated gene regulation.