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bioRxiv · 10.1101/2024.10.14.618161

GLE1 dysfunction compromises cellular homeostasis, spatial organization, and peripheral axon branching

Abstract

The GLE1 protein is an enigmatic factor of RNA processing, associated with multiple developmental disorders including lethal congenital contracture syndrome 1 (LCCS1). Using in vivo genetic engineering to study disturbed GLE1 functions under physiological conditions we demonstrate that inactivation of Gle1 impedes cellular function and organization and causes pre-gastrulation lethality due to defects in adhesion and lineage specification. In contrast, the knock-in mice genocopying LCCS1-associated GLE1FinMajor variant (Gle1PFQ/PFQ) survive prenatal period but die suddenly at mid-adulthood. Gle1PFQ/PFQ mice present irregular count and distribution of spinal motor neurons and impaired development of neural crest-derived tissues as demonstrated by defects in their sympathetic innervation of heart ventricles, paravertebral sympathetic ganglia volume, and adrenal chromaffin cell counts. Unlike previously reported for yeast and HeLa cells, analysis of molecular consequences of GLE1FinMajor variant identified normal poly(A)+ RNA distribution in Gle1PFQ/PFQ cells, which however were impaired in RNA and protein synthesis and simultaneously showed typical signs of cellular senescence. Gle1PFQ/PFQ also induced disturbed stress responses with significant changes in G3BP1-positive stress granule count. Our results show necessity of GLE1 functions for life and indicate that LCCS1 etiology is resultant of pathogenic GLE1FinMajor variant impinging differentiation of neural crest derivatives and leading to complex multiorgan defects. HighlightsO_LITotal inactivation of GLE1 results in disorganization of blastocyst inner cell mass and early embryonic lethality. C_LIO_LIThe Gle1 knock-in (KI) mice, which genocopy the human GLE1FinMajor variant causative for lethal congenital contracture syndrome 1 (LCCS1), die suddenly in mid-adulthood. C_LIO_LINormal poly(A)+ RNA distribution was observed in Gle1 KI cells, but decreased number of G3BP1-positive stress granules were detected in response to stress. C_LIO_LIAbnormal sympathetic innervation of heart ventricles was detected in Gle1 KI mice. C_LIO_LINeural crest-derived tissues represent a new target of GLE1FinMajor and GLE1-related disorders. C_LI

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BibTeXRIS

Zarybnicky, T., Lindfors, S., Metso, S., Szabo, Z., Valtonen, R., Tulppo, M., Magga, J., Saarimaki, S., Blauer, S., Miinalainen, I., Kerkela, R., Vaananen, J., Kivela, R., Zhang, F.-P., Sipila, P., Hinttala, R., Kuure, S.. 2024-10-16. GLE1 dysfunction compromises cellular homeostasis, spatial organization, and peripheral axon branching. https://doi.org/10.1101/2024.10.14.618161

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