5N5C image
Deposition Date 2017-02-13
Release Date 2018-03-14
Last Version Date 2024-06-19
Entry Detail
PDB ID:
5N5C
Keywords:
Title:
NMR solution structure of the TSL2 RNA hairpin
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Method Details:
Experimental Method:
Conformers Calculated:
400
Conformers Submitted:
40
Selection Criteria:
structures with the lowest energy
Macromolecular Entities
Polymer Type:polyribonucleotide
Molecule:RNA (19-MER)
Chain IDs:A
Chain Length:19
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation

Abstact

Modification of SMN2 exon 7 (E7) splicing is a validated therapeutic strategy against spinal muscular atrophy (SMA). However, a target-based approach to identify small-molecule E7 splicing modifiers has not been attempted, which could reveal novel therapies with improved mechanistic insight. Here, we chose as a target the stem-loop RNA structure TSL2, which overlaps with the 5' splicing site of E7. A small-molecule TSL2-binding compound, homocarbonyltopsentin (PK4C9), was identified that increases E7 splicing to therapeutic levels and rescues downstream molecular alterations in SMA cells. High-resolution NMR combined with molecular modelling revealed that PK4C9 binds to pentaloop conformations of TSL2 and promotes a shift to triloop conformations that display enhanced E7 splicing. Collectively, our study validates TSL2 as a target for small-molecule drug discovery in SMA, identifies a novel mechanism of action for an E7 splicing modifier, and sets a precedent for other splicing-mediated diseases where RNA structure could be similarly targeted.

Legend

Protein

Chemical

Disease

Primary Citation of related structures