Germline AGO2 mutations impair RNA interference and human neurological development

Davor Lessel,Marie Mcdonald,Rachel Rabin,Peter Ian Andrews,Linda Ramsdell,Matthew Osmond,Alexander Bartholomäus,Sabine Lüttgen,Katharina Löhner,Rami Abou Jamra,Eng Leong Tan ,Chieko Chijiwa,David A Dyment,Joanna Lazier,Tjitske Kleefstra,John Pappas,Aida Telegrafi,Jonas Denecke,Kirsty Mcwalter,Alexander P.a Stegmann ,Patrick Rump,Thatjana Gardeitchik,Kimberly Foss,Daniela M Zeitler,Margot R.f Reijnders ,Ghayda Mirzaa ,Gunter Meister,Jérémie Mortreux ,Fatemeh Hassani Nia,Andriy Kazantsev,Chantal Missirian,Evelien Zonneveld‐Huijssoon ,Pankaj Prasun,Erica H Gerkes ,Carey‐Anne Evans ,Astrid Bruckmann,Jessika Johannsen,Claudia Schob,Diana Le Duc,Rolph Pfundt,Tiffany Busa,Tanja Kovačević ,Kerith-Rae Dias,Margje Sinnema,Marjolein H Willemsen ,Victoria Martens,Christian Kubisch,Stefan Kindler,Zoya Ignatova,Ilaria Mannucci,Andreas Merkenschlager,Diana Mitter,Lewis Sm ,Ivana Lessel,Henny H Lemmink,Allyn Mcconkie‐Rosell ,Bianca Panis,Breana Cham ,Veronika Graus,Han G Brunner,Bernarda Lozić ,Taila Hartley,Ee‐Shien Tan ,Steffen Syrbe,Kym M Boycott,Tony Roscioli,Hans‐Jürgen Kreienkamp

doi:10.1038/s41467-020-19572-5

Abstract

ARGONAUTE-2 and associated miRNAs form the RNA-induced silencing complex (RISC), which targets mRNAs for translational silencing and degradation as part of the RNA interference pathway. Despite the essential nature of this process for cellular function, there is little information on the role of RISC components in human development and organ function. We identify 13 heterozygous mutations in AGO2 in 21 patients affected by disturbances in neurological development. Each of the identified single amino acid mutations result in impaired shRNA-mediated silencing. We observe either impaired RISC formation or increased binding of AGO2 to mRNA targets as mutation specific functional consequences. The latter is supported by decreased phosphorylation of a C-terminal serine cluster involved in mRNA target release, increased formation of dendritic P-bodies in neurons and global transcriptome alterations in patient-derived primary fibroblasts. Our data emphasize the importance of gene expression regulation through the dynamic AGO2-RNA association for human neuronal development.

Highlights

ARGONAUTE-2 and associated miRNAs form the RNA-induced silencing complex (RISC), which targets mRNAs for translational silencing and degradation as part of the RNA interference pathway
We demonstrate that germline AGO2 mutations affect human neurological development and provide molecular insight into how AGO2 dysfunction causes a human Mendelian disorder
During trio whole-exome sequencing of a cohort of 50 children affected by developmental disturbances and neurological manifestations of unknown etiology[9], we identified a patient bearing a de novo missense mutation p.L192P in AGO2 (NM_012154.5)

Summary

Introduction

ARGONAUTE-2 and associated miRNAs form the RNA-induced silencing complex (RISC), which targets mRNAs for translational silencing and degradation as part of the RNA interference pathway. We observe either impaired RISC formation or increased binding of AGO2 to mRNA targets as mutation specific functional consequences The latter is supported by decreased phosphorylation of a C-terminal serine cluster involved in mRNA target release, increased formation of dendritic P-bodies in neurons and global transcriptome alterations in patient-derived primary fibroblasts. No genetic alterations in the gene encoding for AGO2 have been described which are associated with any human pathology It still remains largely elusive how RNA interference, and especially domains of AGO2 or local sequences down to single amino acid residues, regulate human organismal development and function. We demonstrate that germline AGO2 mutations affect human neurological development and provide molecular insight into how AGO2 dysfunction causes a human Mendelian disorder

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