miRNPs: a novel class of ribonucleoproteins containing numerous microRNAs

Genes Dev. 2002 Mar 15;16(6):720-8. doi: 10.1101/gad.974702.


Gemin3 is a DEAD-box RNA helicase that binds to the Survival of Motor Neurons (SMN) protein and is a component of the SMN complex, which also comprises SMN, Gemin2, Gemin4, Gemin5, and Gemin6. Reduction in SMN protein results in Spinal muscular atrophy (SMA), a common neurodegenerative disease. The SMN complex has critical functions in the assembly/restructuring of diverse ribonucleoprotein (RNP) complexes. Here we report that Gemin3 and Gemin4 are also in a separate complex that contains eIF2C2, a member of the Argonaute protein family. This novel complex is a large approximately 15S RNP that contains numerous microRNAs (miRNAs). We describe 40 miRNAs, a few of which are identical to recently described human miRNAs, a class of small endogenous RNAs. The genomic sequences predict that miRNAs are likely to be derived from larger precursors that have the capacity to form stem-loop structures.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Argonaute Proteins
  • Blotting, Western
  • Centrifugation, Density Gradient
  • Cloning, Molecular
  • DEAD Box Protein 20
  • DEAD-box RNA Helicases
  • Eukaryotic Initiation Factors*
  • HeLa Cells
  • Humans
  • Mice
  • MicroRNAs
  • Minor Histocompatibility Antigens
  • Nerve Tissue Proteins / metabolism
  • Nuclear Proteins / metabolism
  • Nucleic Acid Conformation
  • Peptide Initiation Factors / metabolism
  • Plasmids / metabolism
  • Precipitin Tests
  • Protein Binding
  • Protein Structure, Tertiary
  • RNA Helicases / metabolism
  • RNA, Antisense / chemistry*
  • RNA, Antisense / classification
  • RNA, Messenger / metabolism
  • RNA, Untranslated / chemistry*
  • RNA, Untranslated / classification
  • RNA-Binding Proteins
  • Ribonucleoproteins / chemistry*
  • Ribonucleoproteins / metabolism*
  • Ribonucleoproteins, Small Nuclear
  • SMN Complex Proteins


  • AGO1 protein, human
  • Argonaute Proteins
  • Eukaryotic Initiation Factors
  • GEMIN2 protein, human
  • GEMIN4 protein, human
  • GEMIN5 protein, human
  • GEMIN6 protein, human
  • Gemin5 protein, mouse
  • Gemin6 protein, mouse
  • MicroRNAs
  • Minor Histocompatibility Antigens
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Peptide Initiation Factors
  • RNA, Antisense
  • RNA, Messenger
  • RNA, Untranslated
  • RNA-Binding Proteins
  • Ribonucleoproteins
  • Ribonucleoproteins, Small Nuclear
  • SMN Complex Proteins
  • Sip1 protein, mouse
  • DDX20 protein, human
  • DEAD Box Protein 20
  • Ddx20 protein, mouse
  • DEAD-box RNA Helicases
  • RNA Helicases