Identification of peptide inhibitors of pre-mRNA splicing derived from the essential interaction domains of CDC5L and PLRG1.
CDC5L and PLRG1 are both spliceosomal proteins that are highly conserved across species. They have both been shown to be part of sub- spliceosomal protein complexes that are essential for pre-mRNA splicing in yeast and humans. CDC5L and PLRG1 interact directly in vitro. This interaction is mediated by WD40 regions in PLRG1 and the C-terminal domain of CDC5L. In order to determine whether this interaction is important for the splicing mechanism, we have designed peptides corresponding to highly conserved sequences in the interaction domains of both proteins. These peptides were used in in vitro splicing experiments as competitors to the cognate sequences in the endogenous proteins. Certain peptides derived from the binding domains of both proteins were found to inhibit in vitro splicing. This splicing inhibition could be prevented by preincubating the peptides with the corresponding partner protein that had been expressed in Escherichia coli. The results from this study indicate that the interaction between CDC5L and PLRG1 is essential for pre-mRNA splicing and further demonstrate that small peptides can be used as effective splicing inhibitors.
Ajuh
Paul
P
The University of Dundee, School of Life Sciences, Wellcome Trust Biocentre, Dow Street, Dundee DD1 5EH, UK.
Lamond
Angus I
AI
D000595:Amino Acid Sequence; D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D002457:Cell Extracts; D002467:Cell Nucleus / Q000378:metabolism; D017124:Conserved Sequence; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D017434:Protein Structure, Tertiary; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism*; D012326:RNA Splicing / Q000187:drug effects*; D016415:Sequence Alignment; D017381:Spliceosomes / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D013379:Substrate Specificity
D018797:Cell Cycle Proteins; D002457:Cell Extracts; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; C479410:PLRG1 protein, human; D010446:Peptide Fragments; D012322:RNA Precursors