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Circular Concatemers of Ultra-Short DNA Segments Produce Regulatory RNAs.

ABSTRACT: In the ciliated protozoan Paramecium tetraurelia, Piwi-associated small RNAs are generated upon the elimination of tens of thousands of short transposon-derived DNA segments as part of development. These RNAs then target complementary DNA for elimination in a positive feedback process, contributing to germline defense and genome stability. In this work, we investigate the formation of these RNAs, which we show to be transcribed directly from the short (length mode 27 bp) excised DNA segments. Our data support a mechanism whereby the concatenation and circularization of excised DNA segments provides a template for RNA production. This process allows the generation of a double-stranded RNA for Dicer-like protein cleavage to give rise to a population of small regulatory RNAs that precisely match the excised DNA sequences. VIDEO ABSTRACT.

SUBMITTER: Allen SE

PROVIDER: S-EPMC5346157 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Circular Concatemers of Ultra-Short DNA Segments Produce Regulatory RNAs.

Allen Sarah E SE Hug Iris I Pabian Sylwia S Rzeszutek Iwona I Hoehener Cristina C Nowacki Mariusz M

Cell 20170301 6

In the ciliated protozoan Paramecium tetraurelia, Piwi-associated small RNAs are generated upon the elimination of tens of thousands of short transposon-derived DNA segments as part of development. These RNAs then target complementary DNA for elimination in a positive feedback process, contributing to germline defense and genome stability. In this work, we investigate the formation of these RNAs, which we show to be transcribed directly from the short (length mode 27 bp) excised DNA segments. Ou ...[more]

PMID: 28283070

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