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MiRNPs: a novel class of ribonucleoproteins containing numerous microRNAs.

ABSTRACT: 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.

SUBMITTER: Mourelatos Z

PROVIDER: S-EPMC155365 | biostudies-literature | 2002 Mar

REPOSITORIES: biostudies-literature

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miRNPs: a novel class of ribonucleoproteins containing numerous microRNAs.

Mourelatos Zissimos Z Dostie Josée J Paushkin Sergey S Sharma Anup A Charroux Bernard B Abel Linda L Rappsilber Juri J Mann Matthias M Dreyfuss Gideon G

Genes & development 20020301 6

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 ...[more]

PMID: 11914277

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