An autism model of frk‐knockout with an assessable behavior phenotype in zebrafish is established and key insights into cell proliferation and the influence of the cyp24a1/tp53 pathway‐regulated cell proliferation on frk‐knockout‐induced autism‐like behaviors are provided.
Abstract
Fyn‐related kinase (FRK), which belongs to the Src family of non‐receptor protein tyrosine kinases, functions during the cell cycle. Here, we report an autistic patient with an intragenic mutation of FRK and two other autism‐related genes. Circumventing the barrier of murine model studies, we generated the CRISPR/Cas9‐engineered frk −/− zebrafish. We found that frk‐knockout led to early developmental abnormalities. Frk −/− fish exhibited autism‐like behavior, including impaired social communication, repetitive stereotypic behavior, altered anxiety level, and cognitive dysfunction in both larvae and adults, which could be rescued by the transgenic neuron‐specific re‐expression of frk. GO and KEGG analysis of RNA‐sequencing data found that the frk‐knockout‐induced DEGs were mainly concentrated in processes and functions related to cell metabolism. PPI network analysis of the detected DEGs suggested that the cyp24a1/tp53 pathway may play a key role in frk‐knockout‐induced autism. Furthermore, we found that the numbers of BrdU+ cells were significantly increased in the frk −/− larval brains. Inhibition of Cyp24a1 or activation of tp53 reduced cell proliferation and partially ameliorated social impairments in frk −/− zebrafish. Overall, our work established an autism model of frk‐knockout with an assessable behavior phenotype in zebrafish and provided key insights into cell proliferation and the influence of the cyp24a1/tp53 pathway‐regulated cell proliferation on frk‐knockout‐induced autism‐like behaviors.
Behavioral dysfunction is a common characteristic of many neurodevelopmental and mental health disorders. While the causes of these disorders vary, aberrant behaviors may arise from alterations in transcriptional regulation during early neural development. Because transcription factors (TFs) often belong to families of closely related members, disruption of a single TF may indirectly influence the functionality of other family members. Consequently, mutations in TFs within the same family may lead to overlapping, yet distinct, phenotypes. This feature of TF function has important implications for understanding behavioral phenotypes, but detailed analyses across a single TF family are still lacking. In this study, we present a comprehensive behavioral analysis of adult zebrafish harboring mutations in individual members of the TALE and Hox TF families, that are essential for nervous system development. Using a battery of validated behavioral assays, we uncover elevated stress responses among all TF mutant lines, as well as TF-specific dysregulation in social interaction, locomotion, and endurance. The shared behavioral abnormalities across mutants suggest TF family members converge on core developmental pathways for stress-related behavioral regulation, while mutation-specific phenotypes indicate unique roles for individual TFs in fine-tuning neural function. Our findings provide a systematic behavioral characterization of TALE and Hox mutants in a vertebrate model and provide a framework for understanding how genetic variation within TF families may differentially contribute to vulnerability for neurodevelopmental and mental health disorders.
Austin M. Adkins, K. Glowinski, Yong-Il Kim et al.· Behavior Genetics· 0 citations
Autism spectrum disorder (ASD) is a neurodevelopmental disorder with an unclear pathogenesis. Growing evidence implicates excitatory/inhibitory (E/I) imbalance in ASD pathophysiology, prompting an investigation into gamma-aminobutyric acid (GABA)-mediated inhibitory transmission. The transcription factor Paired Box 2 (Pax2), essential for GABAergic interneuron specification, participates in the regulation of neural developmental processes. Our previous work demonstrated an E/I imbalance in the neurotransmitter system and reduced GABAARα2-positive neurons in the prefrontal cortex (PFC) of Pax2 neuron-specific deletion mice, though the internal molecular regulatory mechanism remained elusive. In this study, we generated GABAergic neuron-specific Pax2 knockdown mice via injection of AAV-shPax2 virus and comprehensively evaluated ASD-related behaviors, revealing autism-like behaviors, such as impaired social novelty and repetitive behaviors. Molecular analysis revealed upregulation of Tcf7l2, a key downstream mediator of the Wnt/β-catenin signaling pathway. Functional assessment confirmed hyperactivation of the Wnt/β-catenin signaling pathway in GABAergic neuron Pax2 knockdown mice. Notably, pharmacological intervention with esculetin, an inhibitor of the Wnt/β-catenin pathway, ameliorated the observed autism-like behaviors. These findings establish a pathogenic axis wherein GABAergic neuron-specific Pax2 deficiency induces hyperactivation of the Wnt/β-catenin signaling pathway and disrupts E/I balance, ultimately driving autism-like behavioral phenotypes. Our results further identify inhibition of Wnt/β-catenin signaling as a promising therapeutic strategy for ASD.
It is indicated that postnatal Hoxa5 deficiency selectively enhances stereotyped behaviors without broadly affecting motor or social functions, which supports a model in which HOXA5 acts as a modulator of postnatal precerebellar circuit connectivity and/or function, with subtle behavioral consequences that require further research in specific genetic or environmental contexts.
Hadrien Glibert, L. Bridoux, C. Moens et al.· Behavioral and Brain Functio...· 0 citations
This study provides substantial evidence for the vital role of trip12 in the early stages of development, as homozygous individuals exhibited early mortality by Day 23 post-fertilization, while a substantial mortality rate was observed by Day 35 in ‘heterozygous’ mutants.
Maider Roibás-Santos, P. Suarez‐Bregua, J. Rotllant et al.· Brain Communications· 0 citations
Human brain development depends on tightly coordinated gene-regulatory programs and the emergence of complex tissue architecture, making large scale functional interrogation difficult using conventional screen models. To overcome this challenge, we used a pooled CRISPR screening approach. Guided by neuro-specific whole-genome screens in Drosophila, we tested 129 poorly characterised human orthologs and found 8 that modify cerebral organoid development. Candidates were validated using individual CRISPR knockouts and mosaic competition assays. Among these candidates we describe FBXW11, a substrate-recognition component of the SCF E3 ubiquitin ligase complex, as a potent negative regulator of cerebral organoid expansion. FBXW11 loss increases radial glial abundance, expands ventricular-like domains, and impairs neuronal maturation. Mechanistically, FBXW11 associates with β-catenin and alters WNT signalling. FBXW11 mutations cause the autosomal-dominant Mendelian syndrome Neurodevelopmental, Jaw, Eye and Digital syndrome (NEDJED), and we found that disease-associated variants mapped preferentially to WD40 substrate-binding repeats and β-catenin contact regions, linking impaired substrate recognition to neurodevelopmental disease. Together, these findings identify FBXW11 as a conserved negative regulator of β-catenin-dependent radial glial expansion and neuronal maturation during human cerebral brain development.
Cesar L. Moreno, Helen E. King, Sophia Trabish et al.· bioRxiv· 0 citations
The findings implicate disrupted SYTL4-RAB27A-dependent vesicle trafficking in ASD pathogenesis and identify SYTL4 and RAB27A as previously unrecognized contributors to autism-associated synaptic deficits and behavior.
Yang Liao, Shuju Zhang, Xiaolei Zhang et al.· Proceedings of the National...· 0 citations