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A fast selenium derivatization strategy for crystallization and phasing of RNA structures.

ABSTRACT: Site-specific 2'-methylseleno RNA labeling is a promising tool for tackling the phase problem in RNA crystallography. We have developed an efficient strategy for crystallization and structure determination of RNA and RNA/protein complexes based on preliminary crystallization screening of 2'-OCH(3)-modified RNA sequences, prior to the replacement of 2'-OCH(3) groups with their 2'-SeCH(3) counterparts. The method exploits the similar crystallization properties of 2'-OCH(3)- and 2'-SeCH(3)-modified RNAs and has been successfully validated for two test cases. In addition, our data show that 2'-SeCH(3)-modified RNA have an increased resistance to X-ray radiolysis in comparison with commonly used 5-halogen-modified RNA, which permits collection of experimental electron density maps of remarkable quality.

SUBMITTER: Olieric V

PROVIDER: S-EPMC2661828 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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A fast selenium derivatization strategy for crystallization and phasing of RNA structures.

Olieric Vincent V Rieder Ulrike U Lang Kathrin K Serganov Alexander A Schulze-Briese Clemens C Micura Ronald R Dumas Philippe P Ennifar Eric E

RNA (New York, N.Y.) 20090218 4

Site-specific 2'-methylseleno RNA labeling is a promising tool for tackling the phase problem in RNA crystallography. We have developed an efficient strategy for crystallization and structure determination of RNA and RNA/protein complexes based on preliminary crystallization screening of 2'-OCH(3)-modified RNA sequences, prior to the replacement of 2'-OCH(3) groups with their 2'-SeCH(3) counterparts. The method exploits the similar crystallization properties of 2'-OCH(3)- and 2'-SeCH(3)-modified ...[more]

PMID: 19228585

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