1
|
Lanjewar AL, Levitt P, Eagleson KL. Developmental and molecular contributions to contextual fear memory emergence in mice. Neuropsychopharmacology 2024:10.1038/s41386-024-01835-0. [PMID: 38438594 DOI: 10.1038/s41386-024-01835-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/02/2024] [Accepted: 02/15/2024] [Indexed: 03/06/2024]
Abstract
Cognitive impairment is a common phenotype of neurodevelopmental disorders, but how these deficits arise remains elusive. Determining the onset of discrete cognitive capabilities facilitates studies in probing mechanisms underlying their emergence. The present study analyzed the emergence of contextual fear memory persistence (7-day memory retention) and remote memory (30-day memory retention). There was a rapid transition from postnatal day (P) 20 to P21, in which memory persistence emerged in C57Bl/6 J male and female mice. Remote memory was present at P23, but expression was not robust compared to pubertal and adult mice. Previous studies reported that following deletion of the MET receptor tyrosine kinase (MET), there are fear memory deficits in adult mice and the timing of critical period plasticity is altered in the developing visual cortex, positioning MET as a regulator for onset of contextual fear memory. Sustaining Met past the normal window of peak cortical expression or deleting Met, however, did not alter the timing of emergence of persistence or remote memory capabilities during development. Fear memory in young adults, however, was disrupted. Remarkably, compared to homecage controls, the number of FOS-expressing infragranular neurons in medial prefrontal cortex (mPFC) did not increase from contextual memory formation recall of fear conditioning at P35 but exhibited enhanced activation at P90 in male and female mice. Additionally, MET-expressing neurons were preferentially recruited at P90 compared to P35 during fear memory expression. The studies demonstrate a developmental profile of contextual fear memory capabilities. Further, developmental disruption of Met leads to a delayed functional deficit that arises in young adulthood, correlated with an increase of mPFC neuron activation during fear memory recall.
Collapse
Affiliation(s)
- Alexandra L Lanjewar
- Program in Developmental Neuroscience and Neurogenetics, Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, USA.
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA.
| | - Pat Levitt
- Program in Developmental Neuroscience and Neurogenetics, Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, USA
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA
| | - Kathie L Eagleson
- Program in Developmental Neuroscience and Neurogenetics, Children's Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, USA
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
2
|
Lanjewar AL, Levitt P, Eagleson KL. Developmental and molecular contributions to contextual fear memory emergence in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.03.527024. [PMID: 36778231 PMCID: PMC9915741 DOI: 10.1101/2023.02.03.527024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Cognitive impairment is a common phenotype of neurodevelopmental disorders, but how these deficits arise remains elusive. Determining the onset of discrete cognitive capabilities facilitates studies in probing mechanisms underlying their emergence. The present study analyzed the emergence of contextual fear memory persistence (7-day memory retention) and remote memory (30-day memory retention). There was a rapid transition from postnatal day (P) 20 to P21, in which memory persistence emerged in C57Bl/6J male and female mice. Remote memory was present at P23, but expression was not robust compared to pubertal and adult mice. Previous studies reported that following deletion of the MET receptor tyrosine kinase (MET), there are fear memory deficits in adult mice and the timing of critical period plasticity is altered in the developing visual cortex, positioning MET as a regulator for onset of contextual fear memory. Sustaining Met past the normal window of peak cortical expression or deleting Met, however, did not alter the timing of emergence of persistence or remote memory capabilities during development. Fear memory in young adults, however, was disrupted. Remarkably, compared to homecage controls, the number of FOS-expressing infragranular neurons in medial prefrontal cortex (mPFC) did not increase from contextual memory formation recall of fear conditioning at P35 but exhibited enhanced activation at P90 in male and female mice. Additionally, MET-expressing neurons were preferentially recruited at P90 compared to P35 during fear memory expression. The studies demonstrate a developmental profile of contextual fear memory capabilities. Further, developmental disruption of Met leads to a delayed functional deficit that arises in young adulthood, correlated with an increase of mPFC neuron activation during fear memory recall.
Collapse
Affiliation(s)
- Alexandra L. Lanjewar
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Pat Levitt
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Kathie L. Eagleson
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
3
|
Eagleson KL, Levitt P. Alterations in the Proteome of Developing Neocortical Synaptosomes in the Absence of MET Signaling Revealed by Comparative Proteomics. Dev Neurosci 2023; 45:126-138. [PMID: 36882009 PMCID: PMC10239366 DOI: 10.1159/000529981] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 02/28/2023] [Indexed: 03/09/2023] Open
Abstract
Alterations in the expression of genes encoding proteins involved in synapse formation, maturation, and function are a hallmark of many neurodevelopmental and psychiatric disorders. For example, there is reduced neocortical expression of the MET receptor tyrosine kinase (MET) transcript and protein in Autism Spectrum Disorder (ASD) and Rett syndrome. Preclinical in vivo and in vitro models manipulating MET signaling reveal that the receptor modulates excitatory synapse development and maturation in select forebrain circuits. The molecular adaptations underlying the altered synaptic development remain unknown. We performed a comparative mass spectrometry analysis of synaptosomes generated from the neocortex of wild type and Met null mice during the peak of synaptogenesis (postnatal day 14; data are available from ProteomeXchange with identifier PXD033204). The analyses revealed broad disruption of the developing synaptic proteome in the absence of MET, consistent with the localization of MET protein in pre- and postsynaptic compartments, including proteins associated with the neocortical synaptic MET interactome and those encoded by syndromic and ASD risk genes. In addition to an overrepresentation of altered proteins associated with the SNARE complex, multiple proteins in the ubiquitin-proteasome system and associated with the synaptic vesicle, as well as proteins that regulate actin filament organization and synaptic vesicle exocytosis/endocytosis, were disrupted. Taken together, the proteomic changes are consistent with structural and functional changes observed following alterations in MET signaling. We hypothesize that the molecular adaptations following Met deletion may reflect a general mechanism that produces circuit-specific molecular changes due to loss or reduction of synaptic signaling proteins.
Collapse
Affiliation(s)
- Kathie L Eagleson
- Department of Pediatrics and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Developmental Neuroscience and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Pat Levitt
- Department of Pediatrics and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA,
- Developmental Neuroscience and Neurogenetics Program, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA,
| |
Collapse
|
4
|
Tsurugizawa T. Translational Magnetic Resonance Imaging in Autism Spectrum Disorder From the Mouse Model to Human. Front Neurosci 2022; 16:872036. [PMID: 35585926 PMCID: PMC9108701 DOI: 10.3389/fnins.2022.872036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 03/30/2022] [Indexed: 11/26/2022] Open
Abstract
Autism spectrum disorder (ASD) is a heterogeneous syndrome characterized by behavioral features such as impaired social communication, repetitive behavior patterns, and a lack of interest in novel objects. A multimodal neuroimaging using magnetic resonance imaging (MRI) in patients with ASD shows highly heterogeneous abnormalities in function and structure in the brain associated with specific behavioral features. To elucidate the mechanism of ASD, several ASD mouse models have been generated, by focusing on some of the ASD risk genes. A specific behavioral feature of an ASD mouse model is caused by an altered gene expression or a modification of a gene product. Using these mouse models, a high field preclinical MRI enables us to non-invasively investigate the neuronal mechanism of the altered brain function associated with the behavior and ASD risk genes. Thus, MRI is a promising translational approach to bridge the gap between mice and humans. This review presents the evidence for multimodal MRI, including functional MRI (fMRI), diffusion tensor imaging (DTI), and volumetric analysis, in ASD mouse models and in patients with ASD and discusses the future directions for the translational study of ASD.
Collapse
Affiliation(s)
- Tomokazu Tsurugizawa
- Human Informatics and Interaction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
- Faculty of Engineering, University of Tsukuba, Tsukuba, Japan
- *Correspondence: Tomokazu Tsurugizawa,
| |
Collapse
|
5
|
Chen K, Ma X, Nehme A, Wei J, Cui Y, Cui Y, Yao D, Wu J, Anderson T, Ferguson D, Levitt P, Qiu S. Time-delimited signaling of MET receptor tyrosine kinase regulates cortical circuit development and critical period plasticity. Mol Psychiatry 2021; 26:3723-3736. [PMID: 31900430 PMCID: PMC7332377 DOI: 10.1038/s41380-019-0635-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 11/25/2019] [Accepted: 12/11/2019] [Indexed: 02/05/2023]
Abstract
Normal development of cortical circuits, including experience-dependent cortical maturation and plasticity, requires precise temporal regulation of gene expression and molecular signaling. Such regulation, and the concomitant impact on plasticity and critical periods, is hypothesized to be disrupted in neurodevelopmental disorders. A protein that may serve such a function is the MET receptor tyrosine kinase, which is tightly regulated developmentally in rodents and primates, and exhibits reduced cortical expression in autism spectrum disorder and Rett Syndrome. We found that the peak of MET expression in developing mouse cortex coincides with the heightened period of synaptogenesis, but is precipitously downregulated prior to extensive synapse pruning and certain peak periods of cortical plasticity. These results reflect a potential on-off regulatory synaptic mechanism for specific glutamatergic cortical circuits in which MET is enriched. In order to address the functional significance of the 'off' component of the proposed mechanism, we created a controllable transgenic mouse line that sustains cortical MET signaling. Continued MET expression in cortical excitatory neurons disrupted synaptic protein profiles, altered neuronal morphology, and impaired visual cortex circuit maturation and connectivity. Remarkably, sustained MET signaling eliminates monocular deprivation-induced ocular dominance plasticity during the normal cortical critical period; while ablating MET signaling leads to early closure of critical period plasticity. The results demonstrate a novel mechanism in which temporal regulation of a pleiotropic signaling protein underlies cortical circuit maturation and timing of cortical critical period, features that may be disrupted in neurodevelopmental disorders.
Collapse
Affiliation(s)
- Ke Chen
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
- MOE Key Laboratory for Neuroinformation, The Clinical Hospital of Chengdu Brain Sciences Institute, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054, China
| | - Xiaokuang Ma
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Antoine Nehme
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Jing Wei
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Yan Cui
- MOE Key Laboratory for Neuroinformation, The Clinical Hospital of Chengdu Brain Sciences Institute, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054, China
| | - Yuehua Cui
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Dezhong Yao
- MOE Key Laboratory for Neuroinformation, The Clinical Hospital of Chengdu Brain Sciences Institute, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054, China
| | - Jie Wu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, 515041, China
- Barrow Neurological Institute, St. Joseph's Hospital Medical Center, Phoenix, AZ, 85013, USA
| | - Trent Anderson
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Deveroux Ferguson
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA
| | - Pat Levitt
- Department of Pediatrics and Program in Developmental Neuroscience and Neurogenetics, The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90027, USA.
| | - Shenfeng Qiu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 85004, USA.
| |
Collapse
|
6
|
Xia B, Wei J, Ma X, Nehme A, Liong K, Cui Y, Chen C, Gallitano A, Ferguson D, Qiu S. Conditional knockout of MET receptor tyrosine kinase in cortical excitatory neurons leads to enhanced learning and memory in young adult mice but early cognitive decline in older adult mice. Neurobiol Learn Mem 2021; 179:107397. [PMID: 33524570 DOI: 10.1016/j.nlm.2021.107397] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 12/22/2020] [Accepted: 01/20/2021] [Indexed: 12/15/2022]
Abstract
Human genetic studies established MET gene as a risk factor for autism spectrum disorders. We have previously shown that signaling mediated by MET receptor tyrosine kinase, expressed in early postnatal developing forebrain circuits, controls glutamatergic neuron morphological development, synapse maturation, and cortical critical period plasticity. Here we investigated how MET signaling affects synaptic plasticity, learning and memory behavior, and whether these effects are age-dependent. We found that in young adult (postnatal 2-3 months) Met conditional knockout (Metfx/fx:emx1cre, cKO) mice, the hippocampus exhibits elevated plasticity, measured by increased magnitude of long-term potentiation (LTP) and depression (LTD) in hippocampal slices. Surprisingly, in older adult cKO mice (10-12 months), LTP and LTD magnitudes were diminished. We further conducted a battery of behavioral tests to assess learning and memory function in cKO mice and littermate controls. Consistent with age-dependent LTP/LTD findings, we observed enhanced spatial memory learning in 2-3 months old young adult mice, assessed by hippocampus-dependent Morris water maze test, but impaired spatial learning in 10-12 months mice. Contextual and cued learning were further assessed using a Pavlovian fear conditioning test, which also revealed enhanced associative fear acquisition and extinction in young adult mice, but impaired fear learning in older adult mice. Lastly, young cKO mice also exhibited enhanced motor learning. Our results suggest that a shift in the window of synaptic plasticity and an age-dependent early cognitive decline may be novel circuit pathophysiology for a well-established autism genetic risk factor.
Collapse
Affiliation(s)
- Baomei Xia
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Jing Wei
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Xiaokuang Ma
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Antoine Nehme
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Katerina Liong
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Yuehua Cui
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Chang Chen
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Amelia Gallitano
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Deveroux Ferguson
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States
| | - Shenfeng Qiu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ 85004, United States.
| |
Collapse
|
7
|
HGF/c-Met Signalling in the Tumor Microenvironment. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1270:31-44. [PMID: 33123991 DOI: 10.1007/978-3-030-47189-7_2] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recently, it has become clearer that tumor plasticity increases the chance that cancer cells could acquire new mechanisms to escape immune surveillance, become resistant to conventional drugs, and spread to distant sites.Effectively, tumor plasticity drives adaptive response of cancer cells to hypoxia and nutrient deprivation leading to stimulation of neoangionesis or tumor escape. Therefore, tumor plasticity is believed to be a great contributor in recurrence and metastatic dissemination of cancer cells. Importantly, it could be an Achilles' heel of cancer if we could identify molecular mechanisms dictating this phenotype.The reactivation of stem-like signalling pathways is considered a great determinant of tumor plasticity; in addition, a key role has been also attributed to tumor microenvironment (TME). Indeed, it has been proved that cancer cells interact with different cells in the surrounding extracellular matrix (ECM). Interestingly, well-established communication represents a potential allied in maintenance of a plastic phenotype in cancer cells supporting tumor growth and spread. An important signalling pathway mediating cancer cell-TME crosstalk is represented by the HGF/c-Met signalling.Here, we review the role of the HGF/c-Met signalling in tumor-stroma crosstalk focusing on novel findings underlying its role in tumor plasticity, immune escape, and development of adaptive mechanisms.
Collapse
|
8
|
Sato H, Imamura R, Suga H, Matsumoto K, Sakai K. Cyclic Peptide-Based Biologics Regulating HGF-MET. Int J Mol Sci 2020; 21:ijms21217977. [PMID: 33121208 PMCID: PMC7662982 DOI: 10.3390/ijms21217977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 02/06/2023] Open
Abstract
Using a random non-standard peptide integrated discovery system, we obtained cyclic peptides that bind to hepatocyte growth factor (HGF) or mesenchymal-epithelial transition factor. (MET) HGF-inhibitory peptide-8 (HiP-8) selectively bound to two-chain active HGF, but not to single-chain precursor HGF. HGF showed a dynamic change in its molecular shape in atomic force microscopy, but HiP-8 inhibited dynamic change in the molecular shape into a static status. The inhibition of the molecular dynamics of HGF by HiP-8 was associated with the loss of the ability to bind MET. HiP-8 could selectively detect active HGF in cancer tissues, and active HGF probed by HiP-8 showed co-localization with activated MET. Using HiP-8, cancer tissues with active HGF could be detected by positron emission tomography. HiP-8 seems to be applicable for the diagnosis and treatment of cancers. In contrast, based on the receptor dimerization as an essential process for activation, the cross-linking of the cyclic peptides that bind to the extracellular region of MET successfully generated an artificial ligand to MET. The synthetic MET agonists activated MET and exhibited biological activities which were indistinguishable from the effects of HGF. MET agonists composed of cyclic peptides can be manufactured by chemical synthesis but not recombinant protein expression, and thus are expected to be new biologics that are applicable to therapeutics and regenerative medicine.
Collapse
Affiliation(s)
- Hiroki Sato
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa 920-1192, Japan; (H.S.); (R.I.); (K.M.)
- WPI-Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
| | - Ryu Imamura
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa 920-1192, Japan; (H.S.); (R.I.); (K.M.)
- WPI-Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan;
| | - Kunio Matsumoto
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa 920-1192, Japan; (H.S.); (R.I.); (K.M.)
- WPI-Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
- Tumor Microenvironment Research Unit, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-1192, Japan
| | - Katsuya Sakai
- Division of Tumor Dynamics and Regulation, Cancer Research Institute, Kanazawa University, Kanazawa 920-1192, Japan; (H.S.); (R.I.); (K.M.)
- WPI-Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kanazawa 920-1192, Japan
- Correspondence:
| |
Collapse
|
9
|
Ma X, Qiu S. Control of cortical synapse development and plasticity by MET receptor tyrosine kinase, a genetic risk factor for autism. J Neurosci Res 2019; 98:2115-2129. [PMID: 31746037 DOI: 10.1002/jnr.24542] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 10/04/2019] [Accepted: 10/04/2019] [Indexed: 12/27/2022]
Abstract
The key developmental milestone events of the human brain, such as neurogenesis, synapse formation, maturation, and plasticity, are determined by a myriad of molecular signaling events, including those mediated by a number of receptor tyrosine kinases (RTKs) and their cognate ligands. Aberrant or mistimed brain development and plasticity can lead to maladaptive changes, such as dysregulated synaptic connectivity and breakdown of circuit functions necessary for cognition and adaptive behaviors, which are hypothesized pathophysiologies of many neurodevelopmental and neuropsychiatric disorders. Here we review recent literature that supports autism spectrum disorder as a likely result of aberrant synapse development due to mistimed maturation and plasticity. We focus on MET RTK, a prominent genetic risk factor for autism, and discuss how a pleiotropic molecular signaling system engaged by MET exemplifies a genetic program that controls cortical circuit development and plasticity by modulating the anatomical and functional connectivity of cortical circuits, thus conferring genetic risk for neurodevelopmental disorders.
Collapse
Affiliation(s)
- Xiaokuang Ma
- Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA
| | - Shenfeng Qiu
- Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA
| |
Collapse
|
10
|
Lauterborn JC, Schultz MN, Le AA, Amani M, Friedman AE, Leach PT, Gall CM, Lynch GS, Crawley JN. Spaced training improves learning in Ts65Dn and Ube3a mouse models of intellectual disabilities. Transl Psychiatry 2019; 9:166. [PMID: 31182707 PMCID: PMC6557858 DOI: 10.1038/s41398-019-0495-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/14/2019] [Accepted: 03/23/2019] [Indexed: 12/29/2022] Open
Abstract
Benefits of distributed learning strategies have been extensively described in the human literature, but minimally investigated in intellectual disability syndromes. We tested the hypothesis that training trials spaced apart in time could improve learning in two distinct genetic mouse models of neurodevelopmental disorders characterized by intellectual impairments. As compared to training with massed trials, spaced training significantly improved learning in both the Ts65Dn trisomy mouse model of Down syndrome and the maternally inherited Ube3a mutant mouse model of Angelman syndrome. Spacing the training trials at 1 h intervals accelerated acquisition of three cognitive tasks by Ts65Dn mice: (1) object location memory, (2) novel object recognition, (3) water maze spatial learning. Further, (4) spaced training improved water maze spatial learning by Ube3a mice. In contrast, (5) cerebellar-mediated rotarod motor learning was not improved by spaced training. Corroborations in three assays, conducted in two model systems, replicated within and across two laboratories, confirm the strength of the findings. Our results indicate strong translational relevance of a behavioral intervention strategy for improving the standard of care in treating the learning difficulties that are characteristic and clinically intractable features of many neurodevelopmental disorders.
Collapse
Affiliation(s)
- J C Lauterborn
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M N Schultz
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
| | - A A Le
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M Amani
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Physiology, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - A E Friedman
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Harvard University, Cambridge, MA, USA
| | - P T Leach
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA
- Biogen Inc., Cambridge, MA, USA
| | - C M Gall
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - G S Lynch
- Department of Anatomy & Neurobiology, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Psychiatry and Human Behavior, School of Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - J N Crawley
- MIND Institute, Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA 95817, USA.
| |
Collapse
|
11
|
Zamolodchikov D, Bai Y, Tang Y, McWhirter JR, Macdonald LE, Alessandri-Haber N. A Short Isoform of Coagulation Factor XII mRNA Is Expressed by Neurons in the Human Brain. Neuroscience 2019; 413:294-307. [PMID: 31181367 DOI: 10.1016/j.neuroscience.2019.05.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/29/2019] [Accepted: 05/21/2019] [Indexed: 01/24/2023]
Abstract
Coagulation factor XII (FXII) is synthesized in the liver and secreted into the circulation, where it initiates the contact activation system. Although typically thought to be restricted to the circulation, FXII protein has been found in the brain of Alzheimer's disease (AD) and multiple sclerosis patients. Moreover, activation of the contact system has been detected in the cerebrospinal fluid of these patients as well as in the brain of healthy and AD individuals. While FXII protein has been detected in the brain, its source and its potential role in brain physiology and/or pathology have not been elucidated. Using in situ hybridization, we show that a shorter FXII mRNA isoform is expressed by neurons in human brain and in the brain of FXII humanized mice, with the highest expression observed in pyramidal neurons. This shorter FXII transcript contains an open reading frame coding for the portion of FXII that spans its proline-rich and catalytic domains (FXII297-596). We show that a recombinant version of this shorter FXII protein is activated by plasma kallikrein, reciprocally activates prekallikrein, and converts pro-hepatocyte growth factor (HGF) to active HGF in vitro. HGF-Met signaling plays a role in neuronal development and survival, and its dysregulation has been implicated in neurodevelopmental disorders and neurodegeneration. Taken together, our results show that a short isoform of FXII mRNA is expressed in the brain and raise the possibility that brain-derived FXII may be involved in HGF-Met signaling in neurons.
Collapse
Affiliation(s)
- Daria Zamolodchikov
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA.
| | - Yu Bai
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Yajun Tang
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - John R McWhirter
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | - Lynn E Macdonald
- Regeneron Pharmaceuticals, Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA
| | | |
Collapse
|
12
|
Ma X, Chen K, Lu Z, Piechowicz M, Liu Q, Wu J, Qiu S. Disruption of MET Receptor Tyrosine Kinase, an Autism Risk Factor, Impairs Developmental Synaptic Plasticity in the Hippocampus. Dev Neurobiol 2019; 79:36-50. [PMID: 30304576 PMCID: PMC6397659 DOI: 10.1002/dneu.22645] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 09/21/2018] [Accepted: 10/10/2018] [Indexed: 02/05/2023]
Abstract
As more genes conferring risks to neurodevelopmental disorders are identified, translating these genetic risk factors into biological mechanisms that impact the trajectory of the developing brain is a critical next step. Here, we report that disrupted signaling mediated MET receptor tyrosine kinase (RTK), an established risk factor for autism spectrum disorders, in the developing hippocampus glutamatergic circuit leads to profound deficits in neural development, synaptic transmission, and plasticity. In cultured hippocampus slices prepared from neonatal mice, pharmacological inhibition of MET kinase activity suppresses dendritic arborization and disrupts normal dendritic spine development. In addition, single-neuron knockdown (RNAi) or overexpression of Met in the developing hippocampal CA1 neurons leads to alterations, opposite in nature, in basal synaptic transmission and long-term plasticity. In forebrain-specific Met conditional knockout mice (Metfx/fx ;emx1cre ), an enhanced long-term potentiation (LTP) and long-term depression (LTD) were observed at early developmental stages (P12-14) at the Schaffer collateral to CA1 synapses compared with wild-type littermates. In contrast, LTP and LTD were markedly reduced at young adult stage (P56-70) during which wild-type mice show robust LTP and LTD. The altered trajectory of synaptic plasticity revealed by this study indicate that temporally regulated MET signaling as an intrinsic, cell autonomous, and pleiotropic mechanism not only critical for neuronal growth and functional maturation, but also for the timing of synaptic plasticity during forebrain glutamatergic circuits development.
Collapse
Affiliation(s)
- Xiaokuang Ma
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Ke Chen
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
- MOE Key Laboratory for NeuroInformation, The Clinical Hospital of Chengdu Brain Sciences Institute, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054, China
| | - Zhongming Lu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
| | - Mariel Piechowicz
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
| | - Qiang Liu
- Barrow Neurological Institute, St. Joseph's Hospital Medical Center, Phoenix, Arizona, 85013
| | - Jie Wu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
- Barrow Neurological Institute, St. Joseph's Hospital Medical Center, Phoenix, Arizona, 85013
- Department of Pharmacology, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Shenfeng Qiu
- Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, 85004
| |
Collapse
|
13
|
Tang S, Powell EM, Zhu W, Lo FS, Erzurumlu RS, Xu S. Altered Forebrain Functional Connectivity and Neurotransmission in a Kinase-Inactive Met Mouse Model of Autism. Mol Imaging 2019; 18:1536012118821034. [PMID: 30799683 PMCID: PMC6322103 DOI: 10.1177/1536012118821034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/13/2018] [Accepted: 12/03/2018] [Indexed: 12/15/2022] Open
Abstract
MET, the gene encoding the tyrosine kinase receptor for hepatocyte growth factor, is a susceptibility gene for autism spectrum disorder (ASD). Genetically altered mice with a kinase-inactive Met offer a potential model for understanding neural circuit organization changes in autism. Here, we focus on the somatosensory thalamocortical circuitry because distinct somatosensory sensitivity phenotypes accompany ASD, and this system plays a major role in sensorimotor and social behaviors in mice. We employed resting-state functional magnetic resonance imaging and in vivo high-resolution proton MR spectroscopy to examine neuronal connectivity and neurotransmission of wild-type, heterozygous Met-Emx1, and fully inactive homozygous Met-Emx1 mice. Met-Emx1 brains showed impaired maturation of large-scale somatosensory network connectivity when compared with wild-type controls. Significant sex × genotype interaction in both network features and glutamate/gamma-aminobutyric acid (GABA) balance was observed. Female Met-Emx1 brains showed significant connectivity and glutamate/GABA balance changes in the somatosensory thalamocortical system when compared with wild-type brains. The glutamate/GABA ratio in the thalamus was correlated with the connectivity between the somatosensory cortex and the thalamus in heterozygous Met-Emx1 female brains. The findings support the hypothesis that aberrant functioning of the somatosensory thalamocortical system is at the core of the conspicuous somatosensory behavioral phenotypes observed in Met-Emx1 mice.
Collapse
Affiliation(s)
- Shiyu Tang
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Elizabeth M. Powell
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Wenjun Zhu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Fu-Sun Lo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Reha S. Erzurumlu
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
14
|
Knoll AT, Jiang K, Levitt P. Quantitative trait locus mapping and analysis of heritable variation in affiliative social behavior and co-occurring traits. GENES, BRAIN, AND BEHAVIOR 2018; 17:e12431. [PMID: 29052939 PMCID: PMC5910301 DOI: 10.1111/gbb.12431] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/04/2017] [Accepted: 10/14/2017] [Indexed: 02/06/2023]
Abstract
Humans exhibit broad heterogeneity in affiliative social behavior. Twin and family studies show that individual differences in core dimensions of social behavior are heritable, yet there are knowledge gaps in understanding the underlying genetic and neurobiological mechanisms. Animal genetic reference panels (GRPs) provide a tractable strategy for examining the behavioral and genetic architecture of complex traits. Here, using males from 50 mouse strains from the BXD GRP, 4 domains of affiliative social behavior-social approach, social recognition, direct social interaction (DSI) (partner sniffing) and vocal communication-were examined in 2 widely used behavioral tasks-the 3-chamber and DSI tasks. There was continuous and broad variation in social and nonsocial traits, with moderate to high heritability of social approach sniff preference (0.31), ultrasonic vocalization (USV) count (0.39), partner sniffing (0.51), locomotor activity (0.54-0.66) and anxiety-like behavior (0.36). Principal component analysis shows that variation in social and nonsocial traits are attributable to 5 independent factors. Genome-wide mapping identified significant quantitative trait loci for USV count on chromosome (Chr) 18 and locomotor activity on Chr X, with suggestive loci and candidate quantitative trait genes identified for all traits with one notable exception-partner sniffing in the DSI task. The results show heritable variation in sociability, which is independent of variation in activity and anxiety-like traits. In addition, a highly heritable and ethological domain of affiliative sociability-partner sniffing-appears highly polygenic. These findings establish a basis for identifying functional natural variants, leading to a new understanding typical and atypical sociability.
Collapse
Affiliation(s)
- A. T. Knoll
- Program in Developmental NeurogeneticsInstitute for the Developing Mind, The Saban Research Institute, Children’s Hospital Los AngelesLos AngelesCA
- Department of PediatricsKeck School of Medicine of the University of Southern CaliforniaLos AngelesCA
| | - K. Jiang
- Department of PediatricsKeck School of Medicine of the University of Southern CaliforniaLos AngelesCA
| | - P. Levitt
- Program in Developmental NeurogeneticsInstitute for the Developing Mind, The Saban Research Institute, Children’s Hospital Los AngelesLos AngelesCA
- Department of PediatricsKeck School of Medicine of the University of Southern CaliforniaLos AngelesCA
| |
Collapse
|
15
|
Lu HC, Mills AA, Tian D. Altered synaptic transmission and maturation of hippocampal CA1 neurons in a mouse model of human chr16p11.2 microdeletion. J Neurophysiol 2017; 119:1005-1018. [PMID: 29212915 DOI: 10.1152/jn.00306.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pathophysiology of neurodevelopmental disorders is often observed early in infancy and toddlerhood. Mouse models of syndromic disorders have provided insight regarding mechanisms of action, but most studies have focused on characterization in juveniles and adults. Insight into developmental trajectories, particularly those related to circuit and synaptic function, will likely yield important information regarding disorder pathogenesis that leads to symptom progression. Chromosome 16p11.2 microdeletion is one of the most common copy number variations associated with a spectrum of neurodevelopmental disorders. Yet, how haploinsufficiency of chr16p11.2 affects early synaptic maturation and function is unknown. To address this knowledge gap, the present study focused on three key components of circuit formation and function, basal synaptic transmission, local circuit function, and maturation of glutamatergic synapses, in developing hippocampal CA1 neurons in a chr16p11.2 microdeletion mouse model. The data demonstrate increased excitability, imbalance in excitation and inhibition, and accelerated maturation of glutamatergic synapses in heterozygous deletion mutant CA1 neurons. Given the critical role of early synaptic development in shaping neuronal connectivity and circuitry formation, these newly identified synaptic abnormalities in chr16p11.2 microdeletion mice may contribute to altered developmental trajectory and function of the developing brain. NEW & NOTEWORTHY The synaptic pathophysiology underlying neurodevelopmental disorders often emerges during infancy and toddlerhood. Therefore, identifying initial changes in synaptic function is crucial for gaining a mechanistic understanding of the pathophysiology, which ultimately will facilitate the design of early interventions. Here, we investigated synaptic and local circuit properties of hippocampal CA1 neurons in a human chr16p11.2 microdeletion mouse model during early postnatal development (preweaning). The data demonstrate increased neuronal excitability, excitatory/inhibitory imbalance, and accelerated maturation of glutamatergic synapses. These perturbations in early hippocampal circuit function may underlie the early pathogenesis of the heterozygous chr16p11.2 microdeletion, which is often associated with epilepsy and intellectual disability.
Collapse
Affiliation(s)
- Hung-Chi Lu
- Department of Pathology and Laboratory Medicine The Saban Research Institute, Children's Hospital Los Angeles, University of Southern California , Los Angeles, California.,Developmental Neuroscience Program, The Saban Research Institute, Children's Hospital Los Angeles, University of Southern California , Los Angeles, California.,Neuroscience Graduate Program, University of Southern California , Los Angeles, California
| | - Alea A Mills
- Cold Spring Harbor Laboratory , Cold Spring Harbor, New York
| | - Di Tian
- Department of Pathology and Laboratory Medicine The Saban Research Institute, Children's Hospital Los Angeles, University of Southern California , Los Angeles, California.,Developmental Neuroscience Program, The Saban Research Institute, Children's Hospital Los Angeles, University of Southern California , Los Angeles, California.,Neuroscience Graduate Program, University of Southern California , Los Angeles, California
| |
Collapse
|
16
|
Heun-Johnson H, Levitt P. Differential impact of Met receptor gene interaction with early-life stress on neuronal morphology and behavior in mice. Neurobiol Stress 2017; 8:10-20. [PMID: 29255778 PMCID: PMC5723381 DOI: 10.1016/j.ynstr.2017.11.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/24/2017] [Accepted: 11/25/2017] [Indexed: 01/01/2023] Open
Abstract
Early adversity in childhood increases the risk of anxiety, mood, and post-traumatic stress disorders in adulthood, and specific gene-by-environment interactions may increase risk further. A common functional variant in the promoter region of the gene encoding the human MET receptor tyrosine kinase (rs1858830 ‘C’ allele) reduces expression of MET and is associated with altered cortical circuit function and structural connectivity. Mice with reduced Met expression exhibit changes in anxiety-like and conditioned fear behavior, precocious synaptic maturation in the hippocampus, and reduced neuronal arbor complexity and synaptogenesis. These phenotypes also can be produced independently by early adversity in wild-type mice. The present study addresses the outcome of combining early-life stress and genetic influences that alter timing of maturation on enduring functional and structural phenotypes. Using a model of reduced Met expression (Met+/−) and early-life stress from postnatal day 2–9, social, anxiety-like, and contextual fear behaviors in later life were measured. Mice that experienced early-life stress exhibited impairments in social interaction, whereas alterations in anxiety-like behavior and fear learning were driven by Met haploinsufficiency, independent of rearing condition. Early-life stress or reduced Met expression decreased arbor complexity of ventral hippocampal CA1 pyramidal neurons projecting to basolateral amygdala. Paradoxically, arbor complexity in Met+/− mice was increased following early-life stress, and thus not different from arbors in wild-type mice raised in control conditions. The changes in dendritic morphology are consistent with the hypothesis that the physiological state of maturation of CA1 neurons in Met+/− mice influences their responsiveness to early-life stress. The dissociation of behavioral and structural changes suggests that there may be phenotype-specific sensitivities to early-life stress.
Collapse
Affiliation(s)
- Hanke Heun-Johnson
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, USA
| | - Pat Levitt
- Institute for the Developing Mind, Children's Hospital Los Angeles, Los Angeles, CA, USA.,Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
17
|
Kato T. Biological roles of hepatocyte growth factor-Met signaling from genetically modified animals. Biomed Rep 2017; 7:495-503. [PMID: 29188052 DOI: 10.3892/br.2017.1001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/26/2017] [Indexed: 12/29/2022] Open
Abstract
Hepatocyte growth factor (HGF) is produced by stromal and mesenchymal cells, and it stimulates epithelial cell proliferation, motility, morphogenesis and angiogenesis in various organs via tyrosine phosphorylation of its cognate receptor, Met. The HGF-Met signaling pathway contributes in a paracrine manner to the development of epithelial organs, exerts regenerative effects on the epithelium, and promotes the regression of fibrosis in numerous organs. Additionally, the HGF-Met signaling pathway is correlated with the biology of cancer types, neurons and immunity. In vivo analyses using genetic modification have markedly increased the profound understanding of the HGF-Met system in basic biology and its clinical applications. HGF and Met knockout (KO) mice are embryonically lethal. Therefore, amino acids in multifunctional docking sites of Met have been exchanged with specific binding motifs for downstream adaptor molecules in order to investigate the signaling potential of the HGF-Met signaling pathway. Conditional Met KO mice were generated using Cre-loxP methodology and characterization of these mice indicated that the HGF-Met signaling pathway is essential in regeneration, protection, and homeostasis in various tissue types and cells. Furthermore, the results of studies using HGF-overexpressing mice have indicated the therapeutic potential of HGF for various types of disease and injury. In the present review, the phenotypes of Met gene-modified mice are summarized.
Collapse
Affiliation(s)
- Takashi Kato
- Urologic Oncology Branch, National Cancer Institute, National Institute of Health, Bethesda, MD 20892, USA
| |
Collapse
|
18
|
Eagleson KL, Xie Z, Levitt P. The Pleiotropic MET Receptor Network: Circuit Development and the Neural-Medical Interface of Autism. Biol Psychiatry 2017; 81:424-433. [PMID: 27837921 PMCID: PMC5285483 DOI: 10.1016/j.biopsych.2016.08.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Revised: 08/11/2016] [Accepted: 08/28/2016] [Indexed: 02/07/2023]
Abstract
People with autism spectrum disorder and other neurodevelopmental disorders (NDDs) are behaviorally and medically heterogeneous. The combination of polygenicity and gene pleiotropy-the influence of one gene on distinct phenotypes-raises questions of how specific genes and their protein products interact to contribute to NDDs. A preponderance of evidence supports developmental and pathophysiological roles for the MET receptor tyrosine kinase, a multifunctional receptor that mediates distinct biological responses depending upon cell context. MET influences neuron architecture and synapse maturation in the forebrain and regulates homeostasis in gastrointestinal and immune systems, both commonly disrupted in NDDs. Peak expression of synapse-enriched MET is conserved across rodent and primate forebrain, yet regional differences in primate neocortex are pronounced, with enrichment in circuits that participate in social information processing. A functional risk allele in the MET promoter, enriched in subgroups of children with autism spectrum disorder, reduces transcription and disrupts socially relevant neural circuits structurally and functionally. In mice, circuit-specific deletion of Met causes distinct atypical behaviors. MET activation increases dendritic complexity and nascent synapse number, but synapse maturation requires reductions in MET. MET mediates its specific biological effects through different intracellular signaling pathways and has a complex protein interactome that is enriched in autism spectrum disorder and other NDD candidates. The interactome is coregulated in developing human neocortex. We suggest that a gene as pleiotropic and highly regulated as MET, together with its interactome, is biologically relevant in normal and pathophysiological contexts, affecting central and peripheral phenotypes that contribute to NDD risk and clinical symptoms.
Collapse
Affiliation(s)
- Kathie L Eagleson
- Program in Developmental Neurogenetics, Institute for the Developing Mind Children's Hospital Los Angeles, CA; Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA
| | - Zhihui Xie
- Program in Developmental Neurogenetics, Institute for the Developing Mind Children's Hospital Los Angeles, CA
| | - Pat Levitt
- Program in Developmental Neurogenetics, Institute for the Developing Mind Children's Hospital Los Angeles, CA; Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA.
| |
Collapse
|
19
|
Xie Z, Li J, Baker J, Eagleson KL, Coba MP, Levitt P. Receptor Tyrosine Kinase MET Interactome and Neurodevelopmental Disorder Partners at the Developing Synapse. Biol Psychiatry 2016; 80:933-942. [PMID: 27086544 PMCID: PMC5001930 DOI: 10.1016/j.biopsych.2016.02.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 07/15/2015] [Accepted: 02/15/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND Atypical synapse development and plasticity are implicated in many neurodevelopmental disorders (NDDs). NDD-associated, high-confidence risk genes have been identified, yet little is known about functional relationships at the level of protein-protein interactions, which are the dominant molecular bases responsible for mediating circuit development. METHODS Proteomics in three independent developing neocortical synaptosomal preparations identified putative interacting proteins of the ligand-activated MET receptor tyrosine kinase, an autism risk gene that mediates synapse development. The candidates were translated into interactome networks and analyzed bioinformatically. Additionally, three independent quantitative proximity ligation assays in cultured neurons and four independent immunoprecipitation analyses of synaptosomes validated protein interactions. RESULTS Approximately 11% (8/72) of MET-interacting proteins, including SHANK3, SYNGAP1, and GRIN2B, are associated with NDDs. Proteins in the MET interactome were translated into a novel MET interactome network based on human protein-protein interaction databases. High-confidence genes from different NDD datasets that encode synaptosomal proteins were analyzed for being enriched in MET interactome proteins. This was found for autism but not schizophrenia, bipolar disorder, major depressive disorder, or attention-deficit/hyperactivity disorder. There is correlated gene expression between MET and its interactive partners in developing human temporal and visual neocortices but not with highly expressed genes that are not in the interactome. Proximity ligation assays and biochemical analyses demonstrate that MET-protein partner interactions are dynamically regulated by receptor activation. CONCLUSIONS The results provide a novel molecular framework for deciphering the functional relations of key regulators of synaptogenesis that contribute to both typical cortical development and to NDDs.
Collapse
Affiliation(s)
- Zhihui Xie
- Department of Pediatrics and The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Jing Li
- Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California
| | - Jonathan Baker
- College of Science, University of Notre Dame, South Bend, Indiana
| | - Kathie L Eagleson
- Department of Pediatrics, Children's Hospital Los Angeles and the Keck School of Medicine of the University of Southern California; Los Angeles, California
| | - Marcelo P Coba
- Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California
| | - Pat Levitt
- Department of Pediatrics, Children's Hospital Los Angeles and the Keck School of Medicine of the University of Southern California; Los Angeles, California; Program in Developmental Neurogenetics, Institute for the Developing Mind and The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California.
| |
Collapse
|
20
|
Yin J, Schaaf CP. Autism genetics - an overview. Prenat Diagn 2016; 37:14-30. [DOI: 10.1002/pd.4942] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 10/04/2016] [Accepted: 10/11/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Jiani Yin
- Department of Molecular and Human Genetics; Baylor College of Medicine; Houston TX USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital; Houston TX USA
| | - Christian P. Schaaf
- Department of Molecular and Human Genetics; Baylor College of Medicine; Houston TX USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital; Houston TX USA
| |
Collapse
|
21
|
Heun-Johnson H, Levitt P. Early-Life Stress Paradigm Transiently Alters Maternal Behavior, Dam-Pup Interactions, and Offspring Vocalizations in Mice. Front Behav Neurosci 2016; 10:142. [PMID: 27458353 PMCID: PMC4932116 DOI: 10.3389/fnbeh.2016.00142] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 06/22/2016] [Indexed: 12/20/2022] Open
Abstract
Animal models can help elucidate the mechanisms through which early-life stress (ELS) has pathophysiological effects on the developing brain. One model that has been developed for rodents consists of limiting the amount of bedding and nesting material during the first postnatal weeks of pup life. This ELS environment has been shown to induce "abusive" behaviors by rat dams towards pups, while mouse dams have been hypothesized to display "fragmented care". Here, as part of an ongoing study of gene-environment interactions that impact brain development, we analyzed long observation periods of wild-type C57Bl/6J dams caring for wild-type and Met heterozygous pups. Met encodes for the MET receptor tyrosine kinase, which is involved in cortical and hippocampal synaptogenesis. Dams with limited resources from postnatal day (P)2 to P9 preserved regular long on-nest periods, and instead increased the number of discrete dam-pup interactions during regular off-nest periods. Immediately after dams entered the nest during off-nest periods in this ELS environment, pups responded to these qualitatively different interactions with an increased number of ultrasonic vocalizations (USV) and audible vocalizations (AV), communication signals that have been associated with aversive and painful stimuli. After returning to control conditions, nest entry behaviors normalized, and dams did not show altered anxiety-like or contextual fear learning behaviors after pup weaning. Furthermore, female mice that had undergone ELS as pups did not show atypical nest entry behaviors in control conditions in adulthood, suggesting that these specific maternal behaviors are not learned during the ELS period. The results suggest that atypical responses of both mother and pups during exposure to this ELS environment likely contribute to long-term negative outcomes in mice, and that these responses more closely resemble the effects of limited bedding on rat dams and pups than was previously suggested. Discerning how different early-life stressors mediate changes in maternal-pup interactions can help elucidate the mechanisms of ELS on brain development and behavior.
Collapse
Affiliation(s)
- Hanke Heun-Johnson
- Neuroscience Graduate Program, University of Southern CaliforniaLos Angeles, CA, USA
| | - Pat Levitt
- Institute for the Developing Mind, Children’s Hospital Los AngelesLos Angeles, CA, USA
- Department of Pediatrics, Keck School of Medicine, University of Southern CaliforniaLos Angeles, CA, USA
| |
Collapse
|