Abstract
BackgroundFINCA disease is a pediatric cerebropulmonary disease caused by variants in the NHL repeat-containing 2 (NHLRC2) gene. Neurological symptoms are among the first manifestations of FINCA disease, but the consequences of NHLRC2 deficiency in the central nervous system are currently unexplored.MethodsThe orthologous mouse gene is essential for development, and its complete loss leads to early embryonic lethality. In the current study, we used CRISPR/Cas9 to generate an Nhlrc2 knockin (KI) mouse line, harboring the FINCA patient missense mutation (c.442G > T, p.Asp148Tyr). A FINCA mouse model, resembling the compound heterozygote genotype of FINCA patients, was obtained by crossing the KI and Nhlrc2 knockout mouse lines. To reveal NHLRC2-interacting proteins in developing neurons, we compared cortical neuronal precursor cells of E13.5 FINCA and wild-type mouse embryos by two-dimensional difference gel electrophoresis.ResultsDespite the significant decrease in NHLRC2, the mice did not develop severe early onset multiorgan disease in either sex. We discovered 19 altered proteins in FINCA neuronal precursor cells; several of which are involved in vesicular transport pathways and actin dynamics which have been previously reported in other cell types including human to have an association with dysfunctional NHLRC2. Interestingly, isoform C2 of hnRNP C1/C2 was significantly increased in both developing neurons and the hippocampus of adult female FINCA mice, connecting NHLRC2 dysfunction with accumulation of RNA binding protein.ConclusionsWe describe here the first NHLRC2-deficient mouse model to overcome embryonic lethality, enabling further studies on predisposing and causative mechanisms behind FINCA disease. Our novel findings suggest that disrupted RNA metabolism may contribute to the neurodegeneration observed in FINCA patients.
Highlights
FINCA disease is a pediatric cerebropulmonary disease caused by variants in the NHL repeat-containing 2 (NHLRC2) gene
The first mouse model for FINCA has significantly decreased NHLRC2 protein levels but normal tissue histology FINCA disease is caused by pathogenic variants in Nhlrc2
Immunoblotting with NHLRC2 antibody recognized a band corresponding to the predicted size of mouse NHLRC2 (78.43 kDa, Uniprot.org, 25.3.20), showing a consistent decrease in all Nhlrc2FINCA/− mouse tissues evaluated (Fig. 1, Additional File 1: S2)
Summary
FINCA disease is a pediatric cerebropulmonary disease caused by variants in the NHL repeat-containing 2 (NHLRC2) gene. Neurological symptoms are among the first manifestations of FINCA disease, but the consequences of NHLRC2 deficiency in the central nervous system are currently unexplored. NHLRC2 mRNA is present in several cell types and regions of the human and mouse brain (Zhang et al 2014,2016). Despite accumulating evidence for the importance of NHLRC2 in the central nervous system, its function in neurons is currently unknown. NHLRC2 consists of an N-terminal thioredoxin (Trx)like domain, a six-bladed β-propeller domain, and a C-terminal β-stranded region (Biterova et al 2018). Structural analysis of the protein has revealed a highly conserved cleft between the Trx-like and β-propeller domains that forms a possible binding site for currently unknown substrates or interaction partners (Biterova et al 2018).
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
