Introns play an essential role in splicing-dependent formation of the exon junction complex.
Pre-mRNA splicing specifically deposits the exon junction complex (EJC) onto spliced mRNA, which is important for downstream events. Here, we show that EJC components are primarily recruited to the spliceosome by association with the intron via the intron-binding protein, IBP160. This initial association of EJC components occurs in the absence of the final EJC-binding site on the exon. RNA interference (RNAi) knockdown of IBP160 arrested EJC association with cytoplasmic RNAs following nonsense-mediated decay. We propose that the intron has a crucial role in the early steps of EJC formation and is indispensable for the subsequent formation of a functional EJC.
Biological Information Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Koto-Ku, Tokyo 135-0064, Japan.
Takashi
T
Ideue
Yasnory T F
YT
Sasaki
Masatoshi
M
Hagiwara
Tetsuro
T
Hirose
D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005091:Exons; D006367:HeLa Cells; D006801:Humans; D066298:In Vitro Techniques; D007438:Introns; D008954:Models, Biological; D034622:RNA Interference; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing; D034741:RNA, Small Interfering / Q000235:genetics; D017381:Spliceosomes / Q000235:genetics / Q000378:metabolism
D004268:DNA-Binding Proteins; D012322:RNA Precursors; D034741:RNA, Small Interfering