Unknown

Dataset Information

0

Glycine decarboxylase deficiency-induced motor dysfunction in zebrafish is rescued by counterbalancing glycine synaptic level.


ABSTRACT: Glycine encephalopathy (GE), or nonketotic hyperglycinemia (NKH), is a rare recessive genetic disease caused by defective glycine cleavage and characterized by increased accumulation of glycine in all tissues. Here, based on new case reports of GLDC loss-of-function mutations in GE patients, we aimed to generate a zebrafish model of severe GE in order to unravel the molecular mechanism of the disease. Using CRISPR/Cas9, we knocked out the gldc gene and showed that gldc-/- fish recapitulate GE on a molecular level and present a motor phenotype reminiscent of severe GE symptoms. The molecular characterization of gldc-/- mutants showed a broad metabolic disturbance affecting amino acids and neurotransmitters other than glycine, with lactic acidosis at stages preceding death. Although a transient imbalance was found in cell proliferation in the brain of gldc-/- zebrafish, the main brain networks were not affected, thus suggesting that GE pathogenicity is mainly due to metabolic defects. We confirmed that the gldc-/- hypotonic phenotype is due to NMDA and glycine receptor overactivation, and demonstrated that gldc-/- larvae depict exacerbated hyperglycinemia at these synapses. Remarkably, we were able to rescue the motor dysfunction of gldc-/- larvae by counterbalancing pharmacologically or genetically the level of glycine at the synapse.

SUBMITTER: Riche R 

PROVIDER: S-EPMC6238748 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

altmetric image

Publications

Glycine decarboxylase deficiency-induced motor dysfunction in zebrafish is rescued by counterbalancing glycine synaptic level.

Riché Raphaëlle R   Liao Meijiang M   Pena Izabella A IA   Leung Kit-Yi KY   Lepage Nathalie N   Greene Nicolas DE NDE   Sarafoglou Kyriakie K   Schimmenti Lisa A LA   Drapeau Pierre P   Samarut Éric É  

JCI insight 20181102 21


Glycine encephalopathy (GE), or nonketotic hyperglycinemia (NKH), is a rare recessive genetic disease caused by defective glycine cleavage and characterized by increased accumulation of glycine in all tissues. Here, based on new case reports of GLDC loss-of-function mutations in GE patients, we aimed to generate a zebrafish model of severe GE in order to unravel the molecular mechanism of the disease. Using CRISPR/Cas9, we knocked out the gldc gene and showed that gldc-/- fish recapitulate GE on  ...[more]

Similar Datasets

| S-EPMC7207170 | biostudies-literature
| S-SCDT-EMM-2019-10722 | biostudies-other
| S-EPMC2576222 | biostudies-literature
| S-EPMC4366506 | biostudies-literature
| S-EPMC3385496 | biostudies-literature
| S-EPMC7806489 | biostudies-literature
| S-EPMC7392897 | biostudies-literature
| S-EPMC2661312 | biostudies-literature
| S-EPMC6377184 | biostudies-literature
| S-EPMC6598340 | biostudies-literature