Decrease Font Size Increase Font Size Email this page to a friend Printer Friendly Page
Life Science > Cell Biology > Learning Center > Pathway Slides & Charts  > Coupled RNA Splicing
Cell Signaling & Neuroscience

Coupled RNA Splicing

Top Border
Left Border  Right Border
Left Corner Back Download Forward Sigma-Aldrich Right Corner

Figure-3b

Coupled RNA Splicing and Nuclear Export

In the schematic, a simplified pre-mRNA with a 5’ cap, 2 exons, a single intron, and a poly(A) tail is shown with the spliceosome. The splicing factor UAP56 (a helicase and DEAD box containing protein family member) associates with Aly and the spliceosome. Heterogeneous nuclear ribonucleoproteins (hnRNPs) package the pre-mRNA and Ser-Arg Rich (SR) proteins associate with exons. Next, the TAP/p15 heterodimer (Mex67/TAP-Mtr2/p15 RNA export receptor) targets the mRNP to the nuclear pore complex (NPC), with Aly acting as a bridge between the exon junction complex (EJC) and the TAP/p15 complex. Finally, mRNA export factors dissociate from the mRNP following export to the cytoplasm. Factors involved in nonsense-mediated mRNA decay (NMD, a conserved mechanism for the detection and elective degradation of mRNAs with premature stop codons) (Upf3, Y14, and RNPS1) remain bound to the mRNP.

Back to Top