Identification of Obelisk-like covalently closed circular RNA replicon in hot springs by double-stranded RNA sequencing and expansion of the diversity of the Obelisk superfamily.

ABSTRACT: Extensive metatranscriptome mining has recently vastly expanded the range of covalently closed circular (ccc) RNA replicons. A notable group of such replicons are Obelisks, cccRNAs of about 1 kilobase (kb) encoding a protein with a unique fold, Oblin-1, and detected in a broad variety of metatranscriptomes, in particular, those from the human gastrointestinal tract. We adopted Fragmented and primer-Ligated DsRNA Sequencing (FLDS) method to selectively sequence double-stranded (ds) RNAs, the replicative intermediates of RNA replicons, and to identify cccRNAs among the resulting sequences. From these data, we selected cccRNAs with predicted extensive intramolecular base-pairing, a hallmark of viroid-like elements. ch We employed FLDS to explore metatranscriptomes from acidic hot springs in J

SUBMITTER: Urayama SI 

PROVIDER: S-EPMC12443047 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature