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Large Scale Mapping of the trimethyl Guanosine Cap on Human RNAs

ABSTRACT: Nucleotides on RNA are chemically modified during biogenesis of various mammalian RNA species and RNA modifications have profound effects on RNA function. The 2,2,7-trimethylguanosine modification of the 5′ of RNA molecules is one of the earliest discovered modified nucleotides on mammalian RNAs. Although the TMG cap is one of the most intensively studied RNA modifications, its distribution on a global scale has not been explored. In this study, the locations of the TMG cap on human RNA is determined, using RNA immunoprecipitation coupled with high-throughput sequencing. Although all prototypical modification sites were supported by this study, modification positions of some RNAs were erroneously annotated. In contrast to prototypic sites, many sites reported later were not validated at all. In addition to annotated modification sites, novel candidate sites were found on small Cajal body-specific RNAs.

ORGANISM(S): Homo sapiens

PROVIDER: GSE277971 | GEO | 2024/09/29

REPOSITORIES: GEO

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