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Heavy-atom labeling of RNA by PLOR for de novo crystallographic phasing.

ABSTRACT: Due to the paucity of known RNA structures, experimental phasing is crucial for obtaining three-dimensional structures of RNAs by X-ray crystallography. Covalent attachment of heavy atoms to RNAs is one of the most useful strategies to facilitate phase determination. However, this approach is limited by the inefficiency or inability to synthesize large RNAs (>60 nucleotides) site-specifically labeled with heavy atoms using traditional methods. Here, we applied our recently reported method, PLOR (position-selective labeling of RNA) to incorporate 5-iodouridine at specific positions in the adenine riboswitch RNA aptamer domain, which was then used for crystallization and subsequent de novo SAD phasing. PLOR is a powerful tool to improve the efficiency of obtaining RNA structures de novo by X-ray crystallography.

SUBMITTER: Stagno JR

PROVIDER: S-EPMC6464214 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Heavy-atom labeling of RNA by PLOR for de novo crystallographic phasing.

Stagno Jason R JR Yu Ping P Dyba Marzena A MA Wang Yun-Xing YX Liu Yu Y

PloS one 20190415 4

Due to the paucity of known RNA structures, experimental phasing is crucial for obtaining three-dimensional structures of RNAs by X-ray crystallography. Covalent attachment of heavy atoms to RNAs is one of the most useful strategies to facilitate phase determination. However, this approach is limited by the inefficiency or inability to synthesize large RNAs (>60 nucleotides) site-specifically labeled with heavy atoms using traditional methods. Here, we applied our recently reported method, PLOR ...[more]

PMID: 30986270

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