Postnatal neurodevelopmental expression and glutamate-dependent regulation of the ZNF804A rodent homologue

Schizophrenia-Like Deficits and Impaired Glutamate/Gamma-aminobutyric acid Homeostasis in Zfp804a Conditional Knockout Mice

BACKGROUND AND HYPOTHESIS

Zinc finger protein 804A (ZNF804A) was the first genome-wide associated susceptibility gene for schizophrenia (SCZ) and played an essential role in the pathophysiology of SCZ by influencing neurodevelopment regulation, neurite outgrowth, synaptic plasticity, and RNA translational control; however, the exact molecular mechanism remains unclear.

STUDY DESIGN

A nervous-system-specific Zfp804a (ZNF804A murine gene) conditional knockout (cKO) mouse model was generated using clustered regularly interspaced short palindromic repeat/Cas9 technology and the Cre/loxP method.

RESULTS

Multiple and complex SCZ-like behaviors, such as anxiety, depression, and impaired cognition, were observed in Zfp804a cKO mice. Molecular biological methods and targeted metabolomics assay validated that Zfp804a cKO mice displayed altered SATB2 (a cortical superficial neuron marker) expression in the cortex; aberrant NeuN, cleaved caspase 3, and DLG4 (markers of mature neurons, apoptosis, and postsynapse, respectively) expressions in the hippocampus and a loss of glutamate (Glu)/γ-aminobutyric acid (GABA) homeostasis with abnormal GAD67 (Gad1) expression in the hippocampus. Clozapine partly ameliorated some SCZ-like behaviors, reversed the disequilibrium of the Glu/GABA ratio, and recovered the expression of GAD67 in cKO mice.

CONCLUSIONS

Zfp804a cKO mice reproducing SCZ-like pathological and behavioral phenotypes were successfully developed. A novel mechanism was determined in which Zfp804a caused Glu/GABA imbalance and reduced GAD67 expression, which was partly recovered by clozapine treatment. These findings underscore the role of altered gene expression in understanding the pathogenesis of SCZ and provide a reliable SCZ model for future therapeutic interventions and biomarker discovery.

ANK3 rs10994336 and ZNF804A rs7597593 polymorphisms: genetic interaction for emotional and behavioral symptoms of alcohol withdrawal syndrome

OBJECTIVE

Alcohol withdrawal syndrome (AWS) is a complex condition associated with alcohol use disorder (AUD), characterized by significant variations in symptom severity among patients. The psychological and emotional symptoms accompanying AWS significantly contribute to withdrawal distress and relapse risk. Despite the importance of neural adaptation processes in AWS, limited genetic investigations have been conducted. This study primarily focuses on exploring the single and interaction effects of single-nucleotide polymorphisms in the ANK3 and ZNF804A genes on anxiety and aggression severity manifested in AWS. By examining genetic associations with withdrawal-related psychopathology, we ultimately aim to advance understanding the genetic underpinnings that modulate AWS severity.

METHODS

The study involved 449 male patients diagnosed with alcohol use disorder. The Self-Rating Anxiety Scale (SAS) and Buss-Perry Aggression Questionnaire (BPAQ) were used to assess emotional and behavioral symptoms related to AWS. Genomic DNA was extracted from peripheral blood, and genotyping was performed using PCR.

RESULTS

Single-gene analysis revealed that naturally occurring allelic variants in ANK3 rs10994336 (CC homozygous vs. T allele carriers) were associated with mood and behavioral symptoms related to AWS. Furthermore, the interaction between ANK3 and ZNF804A was significantly associated with the severity of psychiatric symptoms related to AWS, as indicated by MANOVA. Two-way ANOVA further demonstrated a significant interaction effect between ANK3 rs10994336 and ZNF804A rs7597593 on anxiety, physical aggression, verbal aggression, anger, and hostility. Hierarchical regression analyses confirmed these findings. Additionally, simple effects analysis and multiple comparisons revealed that carriers of the ANK3 rs10994336 T allele experienced more severe AWS, while the ZNF804A rs7597593 T allele appeared to provide protection against the risk associated with the ANK3 rs10994336 mutation.

CONCLUSION

This study highlights the gene-gene interaction between ANK3 and ZNF804A, which plays a crucial role in modulating emotional and behavioral symptoms related to AWS. The ANK3 rs10994336 T allele is identified as a risk allele, while the ZNF804A rs7597593 T allele offers protection against the risk associated with the ANK3 rs10994336 mutation. These findings provide initial support for gene-gene interactions as an explanation for psychiatric risk, offering valuable insights into the pathophysiological mechanisms involved in AWS.

Zinc in Cognitive Impairment and Aging

Zinc, an essential micronutrient for life, was first discovered in 1869 and later found to be indispensable for the normal development of plants and for the normal growth of rats and birds. Zinc plays an important role in many physiological and pathological processes in normal mammalian brain development, especially in the development of the central nervous system. Zinc deficiency can lead to neurodegenerative diseases, mental abnormalities, sleep disorders, tumors, vascular diseases, and other pathological conditions, which can cause cognitive impairment and premature aging. This study aimed to review the important effects of zinc and zinc-associated proteins in cognitive impairment and aging, to reveal its molecular mechanism, and to highlight potential interventions for zinc-associated aging and cognitive impairments.

Schizophrenia-associated variation at ZNF804A correlates with altered experience-dependent dynamics of sleep slow waves and spindles in healthy young adults

The rs1344706 polymorphism in ZNF804A is robustly associated with schizophrenia and schizophrenia is, in turn, associated with abnormal non-rapid eye movement (NREM) sleep neurophysiology. To examine whether rs1344706 is associated with intermediate neurophysiological traits in the absence of disease, we assessed the relationship between genotype, sleep neurophysiology, and sleep-dependent memory consolidation in healthy participants. We recruited healthy adult males with no history of psychiatric disorder from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Participants were homozygous for either the schizophrenia-associated 'A' allele (N = 22) or the alternative 'C' allele (N = 18) at rs1344706. Actigraphy, polysomnography (PSG) and a motor sequence task (MST) were used to characterize daily activity patterns, sleep neurophysiology and sleep-dependent memory consolidation. Average MST learning and sleep-dependent performance improvements were similar across genotype groups, albeit more variable in the AA group. During sleep after learning, CC participants showed increased slow-wave (SW) and spindle amplitudes, plus augmented coupling of SW activity across recording electrodes. SW and spindles in those with the AA genotype were insensitive to learning, whilst SW coherence decreased following MST training. Accordingly, NREM neurophysiology robustly predicted the degree of overnight motor memory consolidation in CC carriers, but not in AA carriers. We describe evidence that rs1344706 polymorphism in ZNF804A is associated with changes in the coordinated neural network activity that supports offline information processing during sleep in a healthy population. These findings highlight the utility of sleep neurophysiology in mapping the impacts of schizophrenia-associated common genetic variants on neural circuit oscillations and function.

Genetic neuroimaging of bipolar disorder: a systematic 2017-2020 update

There is evidence of genetic polymorphism influences on brain structure and function, genetic risk in bipolar disorder (BD), and neuroimaging correlates of BD. How genetic influences related to BD could be reflected on brain changes in BD has been efficiently reviewed in a 2017 systematic review. We aimed to confirm and extend these findings through a Preferred Reporting Items for Systematic reviews and Meta-Analyses-based systematic review. Our study allowed us to conclude that there is no replicated finding in the timeframe considered. We were also unable to further confirm prior results of the BDNF gene polymorphisms to affect brain structure and function in BD. The most consistent finding is an influence of the CACNA1C rs1006737 polymorphism in brain connectivity and grey matter structure and function. There was a tendency of undersized studies to obtain positive results and large, genome-wide polygenic risk studies to find negative results in BD. The neuroimaging genetics in BD field is rapidly expanding.

ZFP804A mutant mice display sex-dependent schizophrenia-like behaviors

Genome-wide association studies uncovered the association of ZNF804A (Zinc-finger protein 804A) with schizophrenia (SZ). In vitro data have indicated that ZNF804A might exert its biological roles by regulating spine and neurite morphogenesis. However, no in vivo data are available for the role of ZNF804A in psychiatric disorders in general, SZ in particular. We generated ZFP804A mutant mice, and they showed deficits in contextual fear and spatial memory. We also observed the sensorimotor gating impairment, as revealed by the prepulse inhibition test, but only in female ZFP804A mutant mice from the age of 6 months. Notably, the PPI difference between the female mutant and control mice was no longer existed with the administration of Clozapine or after the ovariectomy. Hippocampal long-term potentiation was normal in both genders of the mutant mice. Long-term depression was absent in male mutants, but facilitated in the female mutants. Protein levels of hippocampal serotonin-6 receptor and GABAB1 receptor were increased, while those of cortical dopamine 2 receptor were decreased in the female mutants with no obvious changes in the male mutants. Moreover, the spine density was reduced in the cerebral cortex and hippocampus of the mutant mice. Knockdown of ZFP804A impaired the neurite morphogenesis of cortical and hippocampal neurons, while its overexpression enhanced neurite morphogenesis only in the cortical neurons in vitro. Our data collectively support the idea that ZFP804A/ZNF804A plays important roles in the cognitive functions and sensorimotor gating, and its dysfunction may contribute to SZ, particularly in the female patients.

Unravelling the genetic basis of schizophrenia and bipolar disorder with GWAS: A systematic review

OBJECTIVES

To systematically review findings of GWAS in schizophrenia (SZ) and in bipolar disorder (BD); and to interpret findings, with a focus on identifying independent replications.

METHOD

PubMed search, selection and review of all independent GWAS in SZ or BD, published since March 2011, i.e. studies using non-overlapping samples within each article, between articles, and with those of the previous review (Li et al., 2012).

RESULTS

From the 22 GWAS included in this review, the genetic associations surviving standard GWAS-significance were for genetic markers in the regions of ACSL3/KCNE4, ADCY2, AMBRA1, ANK3, BRP44, DTL, FBLN1, HHAT, INTS7, LOC392301, LOC645434/NMBR, LOC729457, LRRFIP1, LSM1, MDM1, MHC, MIR2113/POU3F2, NDST3, NKAPL, ODZ4, PGBD1, RENBP, TRANK1, TSPAN18, TWIST2, UGT1A1/HJURP, WHSC1L1/FGFR1 and ZKSCAN4. All genes implicated across both reviews are discussed in terms of their function and implication in neuropsychiatry.

CONCLUSION

Taking all GWAS to date into account, AMBRA1, ANK3, ARNTL, CDH13, EFHD1 (albeit with different alleles), MHC, PLXNA2 and UGT1A1 have been implicated in either disorder in at least two reportedly non-overlapping samples. Additionally, evidence for a SZ/BD common genetic basis is most strongly supported by the implication of ANK3, NDST3, and PLXNA2.

A promoter variant in ZNF804A decreasing its expression increases the risk of autism spectrum disorder in the Han Chinese population

Synaptic pathology may be one of the cellular substrates underlying autism spectrum disorder (ASD). ZNF804A is a transcription factor that can affect or regulate the expression of many candidate genes involved in ASD. It also localizes at synapses and regulates neuronal and synaptic morphology. So far, few reports have addressed possible associations between ZNF804A polymorphisms and ASD. This study aimed to investigate whether ZNF804A genetic variants contribute to ASD susceptibility and its possible pathological role in the disorder. We analyzed the relationship of two polymorphisms (rs10497655 and rs34714481) in ZNF804A promoter region with ASD in 854 cases versus 926 controls. The functional analyses of rs10497655 were then performed using real-time quantitative polymerase chain reaction, electrophoretic mobility shift assays, chromatin immunoprecipitation and dual-luciferase assays. The variant rs10497655 was significantly associated with ASD (P = 0.007851), which had a significant effect on ZNF804A expression, with the T risk allele homozygotes related with reduced ZNF804A expression in human fetal brains. HSF2 acted as a suppressor by down-regulating ZNF804A expression and had a stronger binding affinity for the T allele of rs10497655 than for the C allele. This was the first experiment to elucidate the process in which a disease-associated SNP affects the level of ZNF804A expression by binding with the upstream regulation factor HSF2. This result indicates that the rs10497655 allelic expression difference of ZNF804A during the critical period of brain development may have an effect on postnatal phenotypes of ASD. It reveals new roles of ZNF804A polymorphisms in the pathogenesis of psychiatric disorders.

Interactome analysis reveals ZNF804A, a schizophrenia risk gene, as a novel component of protein translational machinery critical for embryonic neurodevelopment

Recent genome-wide association studies identified over 100 genetic loci that significantly associate with schizophrenia (SZ). A top candidate gene, ZNF804A, was robustly replicated in different populations. However, its neural functions are largely unknown. Here we show in mouse that ZFP804A, the homolog of ZNF804A, is required for normal progenitor proliferation and neuronal migration. Using a yeast two-hybrid genome-wide screen, we identified novel interacting proteins of ZNF804A. Rather than transcriptional factors, genes involved in mRNA translation are highly represented in our interactome result. ZNF804A co-fractionates with translational machinery and modulates the translational efficiency as well as the mTOR pathway. The ribosomal protein RPSA interacts with ZNF804A and rescues the migration and translational defects caused by ZNF804A knockdown. RNA immunoprecipitation-RNAseq (RIP-Seq) identified transcripts bound to ZFP804A. Consistently, ZFP804A associates with many short transcripts involved in translational and mitochondrial regulation. Moreover, among the transcripts associated with ZFP804A, a SZ risk gene, neurogranin (NRGN), is one of ZFP804A targets. Interestingly, downregulation of ZFP804A decreases NRGN expression and overexpression of NRGN can ameliorate ZFP804A-mediated migration defect. To verify the downstream targets of ZNF804A, a Duolink in situ interaction assay confirmed genes from our RIP-Seq data as the ZNF804A targets. Thus, our work uncovered a novel mechanistic link of a SZ risk gene to neurodevelopment and translational control. The interactome-driven approach here is an effective way for translating genome-wide association findings into novel biological insights of human diseases.

The schizophrenia risk gene ZNF804A: clinical associations, biological mechanisms and neuronal functions

ZNF804A (zinc-finger protein 804A) has been recognized as a schizophrenia risk gene across multiple world populations. Its intronic single-nucleotide polymorphism (SNP) rs1344706 is among one of the strongest susceptibility variants that have achieved genome-wide significance in genome-wide association studies (GWAS) for schizophrenia and has been widely and intensively studied. To elucidate the biological mechanisms underlying the genetic risk conferred by rs1344706, we retrospectively analyzed the progresses in brain gene expression quantitative trait loci (eQTL) analyses, ZNF804A-induced pathway alterations in neural cells and changes in synaptic phenotypes associated with ZNF804A expression. Based on these data, we hypothesize a potential biological mechanism for a genetic risk allele of ZNF804A in schizophrenia pathogenesis. We also review the efforts being made to characterize the affected intermediate phenotypes using neuroimaging and neuropsychological approaches. We then discuss additional common and rare ZNF804A variants in schizophrenia susceptibility and the potential genetic heterogeneity of these genomic loci between Europeans and Asians. This review for we believe the first time systematically presents the evidence for ZNF804A, describing its discovery and likely roles in brain development and schizophrenia pathogenesis. We believe that this work has summarized this information with a systemic and broad assessment of recent findings.

Role of neurodevelopment involved genes in psychiatric comorbidities and modulation of inflammatory processes in Alzheimer's disease

INTRODUCTION

With the increase of the population's average age, Alzheimer's disease (AD) is becoming one of the most disabling diseases worldwide. Recently, neurodevelopment processes have been involved in the AD etiopathogenesis. Genetic studies in this field could contribute to our knowledge and suggest new molecular targets for possible treatments.

METHODS

Our primary aim was to investigate the associations among single nucleotide polymorphisms (SNPs) within neurodevelopment related genes (BDNF, ST8SIA2, C15orf32, NCAPG2, ESYT2, WDR60, LOC154822, VIPR2, GSK3B, NR1I2, ZNF804A, SP4) and AD. A number of exploratory analyses was also performed to evaluate the associations with the presence of behavioral and psychiatric symptoms of dementia (BPSD), as well as with variations in hematological parameters. Two independent samples were investigated, one of 228 Greek subjects and one sample of 229 Italian subjects, including 156Alzheimer's Disease patients CE patients and 301 healthy controls. All patients were affected by late onset AD (LOAD).

RESULTS

None of the analyzed SNPs was associated with AD in our samples. In the exploratory analyses, several genetic variants were associated with inflammation parameters in the Greek sample and in the merged one, suggesting a relationship among these genes and the modulation of inflammation and the immune response. Other exploratory analyses showed associations among several SNPs and psychiatric symptomatology in the Greek sample, suggesting a possible modulation of these variants on psychiatric comorbidities in AD.

CONCLUSIONS

Although we failed to find a direct relationship between AD and the genetic variants investigated, possible connections with inflammation and psychiatric symptoms were suggested.

Genetics of Schizophrenia: Historical Insights and Prevailing Evidence

Schizophrenia's (SZ's) heritability and familial transmission have been known for several decades; however, despite the clear evidence for a genetic component, it has been very difficult to pinpoint specific causative genes. Even so genetic studies have taught us a lot, even in the pregenomic era, about the molecular underpinnings and disease-relevant pathways. Recurring themes emerged revealing the involvement of neurodevelopmental processes, glutamate regulation, and immune system differential activation in SZ etiology. The recent emergence of epigenetic studies aimed at shedding light on the biological mechanisms underlying SZ has provided another layer of information in the investigation of gene and environment interactions. However, this epigenetic insight also brings forth another layer of complexity to the (epi)genomic landscape such as interactions between genetic variants, epigenetic marks-including cross-talk between DNA methylation and histone modification processes-, gene expression regulation, and environmental influences. In this review, we seek to synthesize perspectives, including limitations and obstacles yet to overcome, from genetic and epigenetic literature on SZ through a qualitative review of risk factors and prevailing hypotheses. Encouraged by the findings of both genetic and epigenetic studies to date, as well as the continued development of new technologies to collect and interpret large-scale studies, we are left with a positive outlook for the future of elucidating the molecular genetic mechanisms underlying SZ and other complex neuropsychiatric disorders.