1
|
Görgülü I, Jagannath V, Pons S, Koniuszewski F, Groszer M, Maskos U, Huck S, Scholze P. The human-specific nicotinic receptor subunit CHRFAM7A reduces α7 receptor function in human induced pluripotent stem cells-derived and transgenic mouse neurons. Eur J Neurosci 2024; 60:4893-4906. [PMID: 39073048 DOI: 10.1111/ejn.16474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 06/12/2024] [Accepted: 07/07/2024] [Indexed: 07/30/2024]
Abstract
We investigated the impact of the human-specific gene CHRFAM7A on the function of α7 nicotinic acetylcholine receptors (α7 nAChRs) in two different types of neurons: human-induced pluripotent stem cell (hiPSC)-derived cortical neurons, and superior cervical ganglion (SCG) neurons, taken from transgenic mice expressing CHRFAM7A. dupα7, the gene product of CHRFAM7A, which lacks a major part of the extracellular N-terminal ligand-binding domain, co-assembles with α7, the gene product of CHRNA7. We assessed the receptor function in hiPSC-derived cortical and SCG neurons with Fura-2 calcium imaging and three different α7-specific ligands: PNU282987, choline, and 4BP-TQS. Given the short-lived open state of α7 receptors, we combined the two orthosteric agonists PNU282987 and choline with the type-2 positive allosteric modulator (PAM II) PNU120596. In line with different cellular models used previously, we demonstrate that CHRFAM7A has a major impact on nicotinic α7 nAChRs by reducing calcium transients in response to all three agonists.
Collapse
Affiliation(s)
- Ilayda Görgülü
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Vinita Jagannath
- Institut du Fer à Moulin, Sorbonne University, UMR-S 1270, Paris, France
- MSD R&D Innovation Centre, London, UK
| | - Stephanie Pons
- Integrative Neurobiology of Cholinergic Systems, Institut Pasteur, Université Paris Cité, UMR 3571, Paris, France
| | - Filip Koniuszewski
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Matthias Groszer
- Institut du Fer à Moulin, Sorbonne University, UMR-S 1270, Paris, France
| | - Uwe Maskos
- Integrative Neurobiology of Cholinergic Systems, Institut Pasteur, Université Paris Cité, UMR 3571, Paris, France
| | - Sigismund Huck
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Petra Scholze
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
2
|
Szigeti K, Ihnatovych I, Notari E, Dorn RP, Maly I, He M, Birkaya B, Prasad S, Byrne RS, Indurthi DC, Nimmer E, Heo Y, Retfalvi K, Chaves L, Sule N, Hofmann WA, Auerbach A, Wilding G, Bae Y, Reynolds J. CHRFAM7A diversifies human immune adaption through Ca 2+ signalling and actin cytoskeleton reorganization. EBioMedicine 2024; 103:105093. [PMID: 38569318 PMCID: PMC10999709 DOI: 10.1016/j.ebiom.2024.105093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 03/15/2024] [Accepted: 03/17/2024] [Indexed: 04/05/2024] Open
Abstract
BACKGROUND Human restricted genes contribute to human specific traits in the immune system. CHRFAM7A, a uniquely human fusion gene, is a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR), the highest Ca2+ conductor of the ACh receptors implicated in innate immunity. Understanding the mechanism of how CHRFAM7A affects the immune system remains unexplored. METHODS Two model systems are used, human induced pluripotent stem cells (iPSC) and human primary monocytes, to characterize α7 nAChR function, Ca2+ dynamics and decoders to elucidate the pathway from receptor to phenotype. FINDINGS CHRFAM7A/α7 nAChR is identified as a hypomorphic receptor with mitigated Ca2+ influx and prolonged channel closed state. This shifts the Ca2+ reservoir from the extracellular space to the endoplasmic reticulum (ER) leading to Ca2+ dynamic changes. Ca2+ decoder small GTPase Rac1 is then activated, reorganizing the actin cytoskeleton. Observed actin mediated phenotypes include cellular adhesion, motility, phagocytosis and tissue mechanosensation. INTERPRETATION CHRFAM7A introduces an additional, human specific, layer to Ca2+ regulation leading to an innate immune gain of function. Through the actin cytoskeleton it drives adaptation to the mechanical properties of the tissue environment leading to an ability to invade previously immune restricted niches. Human genetic diversity predicts profound translational significance as its understanding builds the foundation for successful treatments for infectious diseases, sepsis, and cancer metastasis. FUNDING This work is supported in part by the Community Foundation for Greater Buffalo (Kinga Szigeti) and in part by NIH grant R01HL163168 (Yongho Bae).
Collapse
Affiliation(s)
- Kinga Szigeti
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA.
| | - Ivanna Ihnatovych
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Emily Notari
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Ryu P Dorn
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Ivan Maly
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Muye He
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Barbara Birkaya
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Shreyas Prasad
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Robin Schwartz Byrne
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Dinesh C Indurthi
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Erik Nimmer
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Yuna Heo
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Kolos Retfalvi
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Lee Chaves
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Norbert Sule
- Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY, 14203, USA
| | - Wilma A Hofmann
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Anthony Auerbach
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Gregory Wilding
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Yongho Bae
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Jessica Reynolds
- State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| |
Collapse
|
3
|
Jakimovski D, Dorn RP, Regno MD, Bartnik A, Bergsland N, Ramanathan M, Dwyer MG, Benedict RHB, Zivadinov R, Szigeti K. Human restricted CHRFAM7A gene increases brain efficiency. Front Neurosci 2024; 18:1359028. [PMID: 38711941 PMCID: PMC11070550 DOI: 10.3389/fnins.2024.1359028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/12/2024] [Indexed: 05/08/2024] Open
Abstract
Introduction CHRFAM7A, a uniquely human fusion gene, has been associated with neuropsychiatric disorders including Alzheimer's disease, schizophrenia, anxiety, and attention deficit disorder. Understanding the physiological function of CHRFAM7A in the human brain is the first step to uncovering its role in disease. CHRFAM7A was identified as a potent modulator of intracellular calcium and an upstream regulator of Rac1 leading to actin cytoskeleton reorganization and a switch from filopodia to lamellipodia implicating a more efficient neuronal structure. We performed a neurocognitive-MRI correlation exploratory study on 46 normal human subjects to explore the effect of CHRFAM7A on human brain. Methods Dual locus specific genotyping of CHRFAM7A was performed on genomic DNA to determine copy number (TaqMan assay) and orientation (capillary sequencing) of the CHRFAM7A alleles. As only the direct allele is expressed at the protein level and affects α7 nAChR function, direct allele carriers and non-carriers are compared for neuropsychological and MRI measures. Subjects underwent neuropsychological testing to measure motor (Timed 25-foot walk test, 9-hole peg test), cognitive processing speed (Symbol Digit Modalities Test), Learning and memory (California Verbal Learning Test immediate and delayed recall, Brief Visuospatial Memory Test-Revised immediate and delayed recall) and Beck Depression Inventory-Fast Screen, Fatigue Severity Scale. All subjects underwent MRI scanning on the same 3 T GE scanner using the same protocol. Global and tissue-specific volumes were determined using validated cross-sectional algorithms including FSL's Structural Image Evaluation, using Normalization, of Atrophy (SIENAX) and FSL's Integrated Registration and Segmentation Tool (FIRST) on lesion-inpainted images. The cognitive tests were age and years of education-adjusted using analysis of covariance (ANCOVA). Age-adjusted analysis of covariance (ANCOVA) was performed on the MRI data. Results CHRFAM7A direct allele carrier and non-carrier groups included 33 and 13 individuals, respectively. Demographic variables (age and years of education) were comparable. CHRFAM7A direct allele carriers demonstrated an upward shift in cognitive performance including cognitive processing speed, learning and memory, reaching statistical significance in visual immediate recall (FDR corrected p = 0.018). The shift in cognitive performance was associated with smaller whole brain volume (uncorrected p = 0.046) and lower connectivity by resting state functional MRI in the visual network (FDR corrected p = 0.027) accentuating the cognitive findings. Conclusion These data suggest that direct allele carriers harbor a more efficient brain consistent with the cellular biology of actin cytoskeleton and synaptic gain of function. Further larger human studies of cognitive measures correlated with MRI and functional imaging are needed to decipher the impact of CHRFAM7A on brain function.
Collapse
Affiliation(s)
- Dejan Jakimovski
- Department of Neurology, Buffalo Neuroimaging Analysis Center, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Ryu P. Dorn
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Megan Del Regno
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Alexander Bartnik
- Department of Neurology, Buffalo Neuroimaging Analysis Center, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Niels Bergsland
- Department of Neurology, Buffalo Neuroimaging Analysis Center, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Murali Ramanathan
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Michael G. Dwyer
- Department of Neurology, Buffalo Neuroimaging Analysis Center, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
- Center for Biomedical Imaging at the Clinical Translational Science Institute, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Ralph H. B. Benedict
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Robert Zivadinov
- Department of Neurology, Buffalo Neuroimaging Analysis Center, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
- Center for Biomedical Imaging at the Clinical Translational Science Institute, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Kinga Szigeti
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| |
Collapse
|
4
|
Ihnatovych I, Saddler RA, Sule N, Szigeti K. Translational implications of CHRFAM7A, an elusive human-restricted fusion gene. Mol Psychiatry 2024; 29:1020-1032. [PMID: 38200291 PMCID: PMC11176066 DOI: 10.1038/s41380-023-02389-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 12/08/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024]
Abstract
Genes restricted to humans may contribute to human-specific traits and provide a different context for diseases. CHRFAM7A is a uniquely human fusion gene and a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR). The α7 nAChR has been a promising target for diseases affecting cognition and higher cortical functions, however, the treatment effect observed in animal models failed to translate into human clinical trials. As CHRFAM7A was not accounted for in preclinical drug screens it may have contributed to the translational gap. Understanding the complex genetic architecture of the locus, deciphering the functional impact of CHRFAM7A on α7 nAChR neurobiology and utilizing human-relevant models may offer novel approaches to explore α7 nAChR as a drug target.
Collapse
Affiliation(s)
- Ivanna Ihnatovych
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Ruth-Ann Saddler
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA
| | - Norbert Sule
- Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY, 14203, USA
| | - Kinga Szigeti
- Department of Neurology, State University of New York at Buffalo, 875 Ellicott St., Buffalo, NY, 14203, USA.
| |
Collapse
|