WARS1 and SARS1: Two tRNA synthetases implicated in autosomal recessive microcephaly.

Abstract

Aminoacylation of transfer RNA (tRNA) is a key step in protein biosynthesis, carried out by highly specific aminoacyl-tRNA synthetases (ARSs). ARSs have been implicated in autosomal dominant and autosomal recessive human disorders. Autosomal dominant variants in tryptophanyl-tRNA synthetase 1 (WARS1) are known to cause distal hereditary motor neuropathy and Charcot-Marie-Tooth disease, but a recessively inherited phenotype is yet to be clearly defined. Seryl-tRNA synthetase 1 (SARS1) has rarely been implicated in an autosomal recessive developmental disorder. Here, we report five individuals with biallelic missense variants in WARS1 or SARS1, who presented with an overlapping phenotype of microcephaly, developmental delay, intellectual disability, and brain anomalies. Structural mapping showed that the SARS1 variant is located directly within the enzyme's active site, most likely diminishing activity, while the WARS1 variant is located in the N-terminal domain. We further characterize the identified WARS1 variant by showing that it negatively impacts protein abundance and is unable to rescue the phenotype of a CRISPR/Cas9 wars1 knockout zebrafish model. In summary, we describe two overlapping autosomal recessive syndromes caused by variants in WARS1 and SARS1, present functional insights into the pathogenesis of the WARS1-related syndrome and define an emerging disease spectrum: ARS-related developmental disorders with or without microcephaly.

• Authors: Nina Bögershausen, Hannah E Krawczyk, Rami A Jamra, Sheng-Jia Lin, Gökhan Yigit, Irina Hüning, Anna M Polo, Barbara Vona, Kevin Huang, Julia Schmidt, Janine Altmüller, Johannes Luppe, Konrad Platzer, Beate B Dörgeloh, Andreas Busche, Saskia Biskup, Marisa I Mendes, Desiree E C Smith, Gajja S Salomons, Arne Zibat, Eva Bültmann, Peter Nürnberg, Malte Spielmann, Johannes R Lemke, Yun Li, Martin Zenker, Gaurav K Varshney, Hauke S Hillen, Christian P Kratz, Bernd Wollnik
• Journal: Human mutation (Hum Mutat) Vol. 43 Issue 10 Pg. 1454-1471 (10 2022) ISSN: 1098-1004 [Electronic] United States
• PMID: 35790048 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2022 The Authors. Human Mutation published by Wiley Periodicals LLC.

Chemical References

• Amino Acyl-tRNA Synthetases
• Ligases
• RNA, Transfer
• Tryptophan-tRNA Ligase
• WARS1 protein, human
• SARS1 protein, human

Topics

• Animals
• Humans
• Amino Acyl-tRNA Synthetases (genetics)
• Charcot-Marie-Tooth Disease (genetics)
• Ligases
• Microcephaly (genetics, pathology)
• RNA, Transfer
• Tryptophan-tRNA Ligase (genetics)
• Zebrafish (genetics)