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Structural modeling of protein-RNA complexes using crosslinking of segmentally isotope-labeled RNA and MS/MS.

ABSTRACT: Ribonucleoproteins (RNPs) are key regulators of cellular function. We established an efficient approach, crosslinking of segmentally isotope-labeled RNA and tandem mass spectrometry (CLIR-MS/MS), to localize protein-RNA interactions simultaneously at amino acid and nucleotide resolution. The approach was tested on polypyrimidine tract binding protein 1 and U1 small nuclear RNP. Our method provides distance restraints to support integrative atomic-scale structural modeling and to gain mechanistic insights into RNP-regulated processes.

SUBMITTER: Dorn G

PROVIDER: S-EPMC5505470 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Structural modeling of protein-RNA complexes using crosslinking of segmentally isotope-labeled RNA and MS/MS.

Dorn G G Leitner A A Boudet J J Campagne S S von Schroetter C C Moursy A A Aebersold R R Allain F H-T FH

Nature methods 20170327 5

Ribonucleoproteins (RNPs) are key regulators of cellular function. We established an efficient approach, crosslinking of segmentally isotope-labeled RNA and tandem mass spectrometry (CLIR-MS/MS), to localize protein-RNA interactions simultaneously at amino acid and nucleotide resolution. The approach was tested on polypyrimidine tract binding protein 1 and U1 small nuclear RNP. Our method provides distance restraints to support integrative atomic-scale structural modeling and to gain mechanistic ...[more]

PMID: 28346450

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