Publications by authors named "I C MacRae"

Small interfering RNAs (siRNAs) guide mRNA cleavage by human Argonaute2 (hAgo2), leading to targeted gene silencing. Despite their laboratory and clinical impact, structural insights into human siRNA catalytic activity remain elusive. Here, we show that disrupting siRNA 3'-end binding by hAgo2 accelerates target cleavage and stabilizes its catalytic conformation, enabling detailed structural analysis.

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Co-transcriptional assembly is an integral feature of the formation of RNA-protein complexes that mediate translation. For ribosome synthesis, prior studies have indicated that the strict order of transcription of rRNA domains may not be obligatory during bacterial ribosome biogenesis, since a series of circularly permuted rRNAs are viable. In this work, we report the structural insights into assembly of the bacterial ribosome large subunit (LSU) based on cryo-EM density maps of intermediates that accumulate during in vitro ribosome synthesis using a set of circularly permuted (CiPer) rRNAs.

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Article Synopsis
  • Argonaute proteins play essential roles in RNA silencing, helping regulate gene expression and defend against viruses and transposons in eukaryotes, with two main types: AGOs for miRNA/siRNA and PIWIs for piRNA.
  • Research shows that a specific Argonaute protein, HrAgo1, from the Lokiarchaeon 'Candidatus Harpocratesius repetitus,' shares a common ancestry with eukaryotic PIWI proteins and is capable of RNA-guided RNA cleavage.
  • The study suggests that HrAgo1 retains ancient structural features, hinting at how Argonaute proteins might have evolved and diverged in the early stages of eukaryotic development.
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Co-transcriptional assembly is an integral feature of the formation of RNA-protein complexes that mediate translation. For ribosome synthesis, prior studies have indicated that the strict order of transcription of rRNA domains may not be obligatory during bacterial ribosome biogenesis, since a series of circularly permuted rRNAs are viable. In this work, we report the insights into assembly of the bacterial ribosome large subunit (LSU) based on cryo-EM density maps of intermediates that accumulate during ribosome synthesis using a set of circularly permuted (CiPer) rRNAs.

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Background And Aims: Developing novel therapies to battle the global public health burden of heart failure remains challenging. This study investigates the underlying mechanisms and potential treatment for 4-hydroxynonenal (4-HNE) deleterious effects in heart failure.

Methods: Biochemical, functional, and histochemical measurements were applied to identify 4-HNE adducts in rat and human failing hearts.

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