Identification of novel argonaute-associated proteins.
RNA silencing processes are guided by small RNAs known as siRNAs and microRNAs (miRNAs) . They reside in ribonucleoprotein complexes, which guide the cleavage of complementary mRNAs or affect stability and translation of partial complementary mRNAs . Argonaute (Ago) proteins are at the heart of silencing effector complexes and bind the single-stranded siRNA and miRNA . Our biochemical analysis revealed that Ago2 is present in a pre-miRNA processing complex that is able to transfer the miRNA into a target-mRNA cleaving complex. To gain insight into the function and composition of RNA silencing complexes, we purified Ago1- and Ago2-containing complexes from human cells. Several known Ago1- and/or Ago2-associated proteins including Dicer were identified, but also two novel factors, the putative RNA helicase MOV10, and the RNA recognition motif (RRM)-containing protein TNRC6B/KIAA1093. The new proteins localize, similar to Ago proteins, to mRNA-degrading cytoplasmic P bodies, and they are functionally required to mediate miRNA-guided mRNA cleavage.
Pubmed ID: 16289642 RIS Download
Argonaute Proteins | Blotting, Northern | Blotting, Western | Cell Line | Eukaryotic Initiation Factor-2 | Eukaryotic Initiation Factors | Fluorescent Antibody Technique | Humans | Intracellular Signaling Peptides and Proteins | Mass Spectrometry | MicroRNAs | Oligonucleotides | Peptide Initiation Factors | RNA Helicases | RNA, Messenger | RNA, Small Interfering | RNA-Induced Silencing Complex | Reverse Transcriptase Polymerase Chain Reaction | Ribonuclease III