Communication of the Position of Exon-Exon Junctions to the mRNA Surveillance Machinery by the Protein RNPS1

@article{LykkeAndersen2001CommunicationOT,
  title={Communication of the Position of Exon-Exon Junctions to the mRNA Surveillance Machinery by the Protein RNPS1},
  author={Jens Lykke-Andersen and M D Shu and Joan A. Steitz},
  journal={Science},
  year={2001},
  volume={293},
  pages={1836 - 1839}
}
In mammalian cells, splice junctions play a dual role in mRNA quality control: They mediate selective nuclear export of mature mRNA and they serve as a mark for mRNA surveillance, which subjects aberrant mRNAs with premature termination codons to nonsense-mediated decay (NMD). Here, we demonstrate that the protein RNPS1, a component of the postsplicing complex that is deposited 5′ to exon-exon junctions, interacts with the evolutionarily conserved human Upf complex, a central component of NMD… 

The nonsense-mediated decay RNA surveillance pathway.

Whether these proofreading events preferentially occur during a "pioneer" round of translation in higher and lower eukaryotes, their cellular location, and whether they can use alternative EJC factors or act independent of the EJC are discussed.

Splicing of U12-type introns deposits an exon junction complex competent to induce nonsense-mediated mRNA decay

In vitro splicing of a U12-type intron assembles an exon junction complex (EJC) that is comparably positioned and contains many of the same components as that deposited by the U2-type spliceosome.

Splicing enhances translation in mammalian cells: an additional function of the exon junction complex.

In mammalian cells, increased translational yield correlates with enhanced cytoplasmic polysome association of spliced mRNAs, and is attributable to deposition of exon junction complexes (EJCs).

5' exon interactions within the human spliceosome establish a framework for exon junction complex structure and assembly.

A general consequence of pre-mRNA splicing is the stable deposition of several proteins 20-24 nucleotides (nt) upstream of exon-exon junctions on spliced mRNAs. This exon junction complex (EJC)

A Day in the Life of the Exon Junction Complex

The most important functions and main protagonists in the life of the exon junction complex are summarized and the latest findings on the assembly, composition and molecular activities of the EJC are provided.

No-nonsense: insights into the functional interplay of nonsense-mediated mRNA decay factors

The coexistence and function of different isoforms of up-frameshift protein 1 with an emphasis of their role at the endoplasmic reticulum and during stress are highlighted, underscoring that gene regulation by mammalian NMD is tightly controlled and context-dependent being conditional on developmental stage, tissue and cell types.
...

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