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Updated: Jul 4, 2026
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Exploring Sequence Space to Identify Binding Sites for Regulatory RNA-Binding Proteins
Published on: August 9, 2019
L30 binds the nascent RPL30 transcript to repress U2 snRNP recruitment
Sara Macías1, Mireia Bragulat, Daniel F Tardiff
1Centre de Regulació Genòmica, Doctor Aiguader 88, 08003 Barcelona, Spain.
Molecular Cell
|June 24, 2008
Summary
The ribosomal L30 protein in Saccharomyces cerevisiae binds its pre-mRNA, blocking essential U2 snRNP association with the branch site. This regulation prevents proper splicing by inhibiting a key spliceosomal rearrangement.
Area of Science:
- Molecular Biology
- Gene Regulation
- RNA Processing
Background:
- Mechanisms of pre-messenger RNA (pre-mRNA) splicing regulation are not fully understood.
- Autoregulation is a common mechanism for controlling gene expression.
Purpose of the Study:
- To investigate how Saccharomyces cerevisiae ribosomal protein L30 (Rpl30) regulates its own pre-mRNA splicing.
- To elucidate the molecular mechanism by which Rpl30 inhibits splicing.
Main Methods:
- Biochemical assays to study protein-RNA interactions.
- Analysis of spliceosome assembly and function in vitro and in vivo.
- Mutational analysis of Rpl30 and its target RNA structure.
Main Results:
- Rpl30 binds to a kink-turn structure in its nascent pre-mRNA, encompassing the 5' splice site.
- Rpl30 binding does not impede U1 small nuclear ribonucleoprotein (snRNP) recognition but blocks U2 snRNP association with the branch site.
- Rpl30 inhibition is independent of BBP, Mud2, Sub2, and Cus2, factors involved in early spliceosome assembly and branch site recognition.
- Unlike a heterologous protein, Rpl30 does not completely block intron recognition.
Conclusions:
- Rpl30 represses pre-mRNA splicing by inhibiting a critical spliceosomal rearrangement necessary for U2 snRNP binding.
- This study reveals a novel mechanism of autoregulation at the level of splicing initiation.
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