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Transcriptomic analysis of HAP1 DEGS1 KO cells and their wildtype counterpart

ABSTRACT: Genetic variants in sphingolipid metabolizing enzymes are known to cause neurodegenerative and metabolic diseases by altering the cellular sphingolipid composition. Dysfunction of delta4-dihydroceramide (dhCer) desaturase (DEGS1) has recently been associated with a rare human monogenic neurological disease affecting sphingolipid (SL) homeostasis. Patients with pathogenic DEGS1 variants show elevated levels of different dhCer species and develop a hypomyelinating leukodystrophy in early childhood. To better understand the human pathophysiology and mechanistic complexity of this severe and progressive disease, we here utilized human DEGS1-knockout (KO) HAP1 cells as a genetic KO model to comprehensively investigate the effects of elevated dihydroceramide species on various intracellular processes, like autophagy, apoptosis, ROS formation and ER Stress by using flow cytometry, Western Blot and fluorescence microscopy. DEGS1 KO cells show elevated ROS levels, enhanced autophagy and apoptosis, impaired lysosomal integrity and mild mitochondrial dysfunction. Furthermore, whole transcriptome analysis of DEGS1 KO cells by global RNA sequencing identified impaired processes associated to neuronal differentiation and synaptic function. Morphometric quantification of neuronal features in cultured primary neurons could substantiate RNA-seq results by showing a strong reduction of neuronal complexity 24 hours after Degs1-knockdown and thus impairment of neurodevelopment. In conclusion, we here demonstrate haploid DEGS1-KO cells as a valuable in vitro model for comprehensive mechanistic studies of inherited neurodegenerative diseases.

ORGANISM(S): Homo sapiens

PROVIDER: GSE213289 | GEO | 2023/01/02

REPOSITORIES: GEO

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