1
|
Calabrese B, Halpain S. MARCKS and PI(4,5)P 2 reciprocally regulate actin-based dendritic spine morphology. Mol Biol Cell 2024; 35:ar23. [PMID: 38088877 PMCID: PMC10881156 DOI: 10.1091/mbc.e23-09-0370] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/27/2023] [Accepted: 12/07/2023] [Indexed: 01/14/2024] Open
Abstract
Myristoylated, alanine-rich C-kinase substrate (MARCKS) is an F-actin and phospholipid binding protein implicated in numerous cellular activities, including the regulation of morphology in neuronal dendrites and dendritic spines. MARCKS contains a lysine-rich effector domain that mediates its binding to plasma membrane phosphatidylinositol-4,5-biphosphate (PI(4,5)P2) in a manner controlled by PKC and calcium/calmodulin. In neurons, manipulations of MARCKS concentration and membrane targeting strongly affect the numbers, shapes, and F-actin properties of dendritic spines, but the mechanisms remain unclear. Here, we tested the hypothesis that the effects of MARCKS on dendritic spine morphology are due to its capacity to regulate the availability of plasma membrane PI(4,5)P2. We observed that the concentration of free PI(4,5)P2 on the dendritic plasma membrane was inversely proportional to the concentration of MARCKS. Endogenous PI(4,5)P2 levels were increased or decreased, respectively, by acutely overexpressing either phosphatidylinositol-4-phosphate 5-kinase (PIP5K) or inositol polyphosphate 5-phosphatase (5ptase). PIP5K, like MARCKS depletion, induced severe spine shrinkage; 5ptase, like constitutively membrane-bound MARCKS, induced aberrant spine elongation. These phenotypes involved changes in actin properties driven by the F-actin severing protein cofilin. Collectively, these findings support a model in which neuronal activity regulates actin-dependent spine morphology through antagonistic interactions of MARCKS and PI(4,5)P2.
Collapse
Affiliation(s)
- Barbara Calabrese
- Department of Neurobiology, School of Biological Sciences, University of California San Diego and Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037
| | - Shelley Halpain
- Department of Neurobiology, School of Biological Sciences, University of California San Diego and Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037
| |
Collapse
|
2
|
Zhu Y, Hui Q, Zhang Z, Fu H, Qin Y, Zhao Q, Li Q, Zhang J, Guo L, He W, Han C. Advancements in the study of synaptic plasticity and mitochondrial autophagy relationship. J Neurosci Res 2024; 102:e25309. [PMID: 38400573 DOI: 10.1002/jnr.25309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 01/26/2024] [Accepted: 01/31/2024] [Indexed: 02/25/2024]
Abstract
Synapses serve as the points of communication between neurons, consisting primarily of three components: the presynaptic membrane, synaptic cleft, and postsynaptic membrane. They transmit signals through the release and reception of neurotransmitters. Synaptic plasticity, the ability of synapses to undergo structural and functional changes, is influenced by proteins such as growth-associated proteins, synaptic vesicle proteins, postsynaptic density proteins, and neurotrophic growth factors. Furthermore, maintaining synaptic plasticity consumes more than half of the brain's energy, with a significant portion of this energy originating from ATP generated through mitochondrial energy metabolism. Consequently, the quantity, distribution, transport, and function of mitochondria impact the stability of brain energy metabolism, thereby participating in the regulation of fundamental processes in synaptic plasticity, including neuronal differentiation, neurite outgrowth, synapse formation, and neurotransmitter release. This article provides a comprehensive overview of the proteins associated with presynaptic plasticity, postsynaptic plasticity, and common factors between the two, as well as the relationship between mitochondrial energy metabolism and synaptic plasticity.
Collapse
Affiliation(s)
- Yousong Zhu
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Qinlong Hui
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Zheng Zhang
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Hao Fu
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Yali Qin
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Qiong Zhao
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Qinqing Li
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| | - Junlong Zhang
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
| | - Lei Guo
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
| | - Wenbin He
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
| | - Cheng Han
- Shanxi Key Laboratory of Chinese Medicine Encephalopathy, Jinzhong, China
- National International Joint Research Center for Molecular Traditional Chinese Medicine, Jinzhong, China
- Basic Medical College of Shanxi University of Chinese Medicine, Jinzhong, China
| |
Collapse
|
3
|
Rodríguez-Vega A, Dutra-Tavares AC, Souza TP, Semeão KA, Filgueiras CC, Ribeiro-Carvalho A, Manhães AC, Abreu-Villaça Y. Nicotine Exposure in a Phencyclidine-Induced Mice Model of Schizophrenia: Sex-Selective Medial Prefrontal Cortex Protein Markers of the Combined Insults in Adolescent Mice. Int J Mol Sci 2023; 24:14634. [PMID: 37834084 PMCID: PMC10572990 DOI: 10.3390/ijms241914634] [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: 07/19/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
Tobacco misuse as a comorbidity of schizophrenia is frequently established during adolescence. However, comorbidity markers are still missing. Here, the method of label-free proteomics was used to identify deregulated proteins in the medial prefrontal cortex (prelimbic and infralimbic) of male and female mice modelled to schizophrenia with a history of nicotine exposure during adolescence. Phencyclidine (PCP), used to model schizophrenia (SCHZ), was combined with an established model of nicotine minipump infusions (NIC). The combined insults led to worse outcomes than each insult separately when considering the absolute number of deregulated proteins and that of exclusively deregulated ones. Partially shared Reactome pathways between sexes and between PCP, NIC and PCPNIC groups indicate functional overlaps. Distinctively, proteins differentially expressed exclusively in PCPNIC mice reveal unique effects associated with the comorbidity model. Interactome maps of these proteins identified sex-selective subnetworks, within which some proteins stood out: for females, peptidyl-prolyl cis-trans isomerase (Fkbp1a) and heat shock 70 kDa protein 1B (Hspa1b), both components of the oxidative stress subnetwork, and gamma-enolase (Eno2), a component of the energy metabolism subnetwork; and for males, amphiphysin (Amph), a component of the synaptic transmission subnetwork. These are proposed to be further investigated and validated as markers of the combined insult during adolescence.
Collapse
Affiliation(s)
- Andrés Rodríguez-Vega
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Ana Carolina Dutra-Tavares
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Thainá P. Souza
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Keila A. Semeão
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Claudio C. Filgueiras
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Anderson Ribeiro-Carvalho
- Departamento de Ciências, Faculdade de Formação de Professores da Universidade do Estado do Rio de Janeiro, São Gonçalo 24435-005, RJ, Brazil;
| | - Alex C. Manhães
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| | - Yael Abreu-Villaça
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro 20550-170, RJ, Brazil; (A.R.-V.); (A.C.D.-T.); (T.P.S.); (K.A.S.); (C.C.F.); (A.C.M.)
| |
Collapse
|
4
|
Seo J, Hwang H, Choi Y, Jung S, Hong JH, Yoon BJ, Rhim H, Park M. Myristoylation-dependent palmitoylation of cyclin Y modulates long-term potentiation and spatial learning. Prog Neurobiol 2022; 218:102349. [PMID: 36030931 DOI: 10.1016/j.pneurobio.2022.102349] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 07/13/2022] [Accepted: 08/22/2022] [Indexed: 11/16/2022]
Abstract
Many psychiatric disorders accompany deficits in cognitive functions and synaptic plasticity, and abnormal lipid modifications of neuronal proteins are associated with their pathophysiology. Lipid modifications, including palmitoylation and myristoylation, play crucial roles in the subcellular localization and trafficking of proteins. Cyclin Y (CCNY), enriched in the postsynaptic compartment, acts as an inhibitory modulator of functional and structural long-term potentiation (LTP) in the hippocampal neurons. However, cellular and molecular mechanisms underlying CCNY-mediated inhibitory functions in the synapse remain largely unknown. Here, we report that myristoylation located CCNY to the trans-Golgi network (TGN), and subsequent palmitoylation directed the myristoylated CCNY from the TGN to the synaptic cell surface. This myristoylation-dependent palmitoylation of CCNY was required for the inhibitory role of CCNY in excitatory synaptic transmission, activity-induced dynamics of AMPA receptors and PSD-95, LTP, and spatial learning. Furthermore, spatial learning significantly reduced palmitoyl- and myristoyl-CCNY levels, indicating that spatial learning lowers the synaptic abundance of CCNY. Our findings provide mechanistic insight into how CCNY is clustered adjacent to postsynaptic sites where it could play its inhibitory roles in synaptic plasticity and spatial learning.
Collapse
Affiliation(s)
- Jiyeon Seo
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Hongik Hwang
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Yuri Choi
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Sunmin Jung
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea
| | - Jung-Hwa Hong
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Department of Life Sciences, Korea University, Seoul 02841, South Korea
| | - Bong-June Yoon
- Department of Life Sciences, Korea University, Seoul 02841, South Korea
| | - Hyewhon Rhim
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, South Korea
| | - Mikyoung Park
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, South Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul 02792, South Korea.
| |
Collapse
|
5
|
Roychaudhuri R, Snyder SH. Mammalian D-cysteine: A novel regulator of neural progenitor cell proliferation: Endogenous D-cysteine, the stereoisomer with rapid spontaneous in vitro racemization rate, has major neural roles: Endogenous D-cysteine, the stereoisomer with rapid spontaneous in vitro racemization rate, has major neural roles. Bioessays 2022; 44:e2200002. [PMID: 35484375 DOI: 10.1002/bies.202200002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/25/2022] [Accepted: 04/12/2022] [Indexed: 12/15/2022]
Abstract
D-amino acids are being recognized as functionally important molecules in mammals. We recently identified endogenous D-cysteine in mammalian brain. D-cysteine is present in neonatal brain in substantial amounts (mM) and decreases with postnatal development. D-cysteine binds to MARCKS and a host of proteins implicated in cell division and neurodevelopmental disorders. D-cysteine decreases phosphorylation of MARCKS in neural progenitor cells (NPCs) affecting its translocation. D-cysteine controls NPC proliferation by inhibiting AKT signaling. Exogenous D-cysteine inhibits AKT phosphorylation at Thr 308 and Ser 473 in NPCs. D-cysteine treatment of NPCs led to 50% reduction in phosphorylation of Foxo1 at Ser 256 and Foxo3a at Ser 253. We hypothesize that in the developing brain endogenous D-cysteine is as a physiologic regulator of NPC proliferation by inhibiting AKT signaling mediated by Foxo1 and Foxo3a. Endogenous D-cysteine may regulate mammalian neurodevelopment with roles in schizophrenia and Alzheimer's disease (AD).
Collapse
Affiliation(s)
- Robin Roychaudhuri
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Solomon H Snyder
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
6
|
D-cysteine is an endogenous regulator of neural progenitor cell dynamics in the mammalian brain. Proc Natl Acad Sci U S A 2021; 118:2110610118. [PMID: 34556581 DOI: 10.1073/pnas.2110610118] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2021] [Indexed: 12/19/2022] Open
Abstract
d-amino acids are increasingly recognized as important signaling molecules in the mammalian central nervous system. However, the d-stereoisomer of the amino acid with the fastest spontaneous racemization ratein vitro in vitro, cysteine, has not been examined in mammals. Using chiral high-performance liquid chromatography and a stereospecific luciferase assay, we identify endogenous d-cysteine in the mammalian brain. We identify serine racemase (SR), which generates the N-methyl-d-aspartate (NMDA) glutamate receptor coagonist d-serine, as a candidate biosynthetic enzyme for d-cysteine. d-cysteine is enriched more than 20-fold in the embryonic mouse brain compared with the adult brain. d-cysteine reduces the proliferation of cultured mouse embryonic neural progenitor cells (NPCs) by ∼50%, effects not shared with d-serine or l-cysteine. The antiproliferative effect of d-cysteine is mediated by the transcription factors FoxO1 and FoxO3a. The selective influence of d-cysteine on NPC proliferation is reflected in overgrowth and aberrant lamination of the cerebral cortex in neonatal SR knockout mice. Finally, we perform an unbiased screen for d-cysteine-binding proteins in NPCs by immunoprecipitation with a d-cysteine-specific antibody followed by mass spectrometry. This approach identifies myristoylated alanine-rich C-kinase substrate (MARCKS) as a putative d-cysteine-binding protein. Together, these results establish endogenous mammalian d-cysteine and implicate it as a physiologic regulator of NPC homeostasis in the developing brain.
Collapse
|
7
|
Tendilla-Beltrán H, Sanchez-Islas NDC, Marina-Ramos M, Leza JC, Flores G. The prefrontal cortex as a target for atypical antipsychotics in schizophrenia, lessons of neurodevelopmental animal models. Prog Neurobiol 2020; 199:101967. [PMID: 33271238 DOI: 10.1016/j.pneurobio.2020.101967] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 10/10/2020] [Accepted: 11/22/2020] [Indexed: 02/06/2023]
Abstract
Prefrontal cortex (PFC) inflammatory imbalance, oxidative/nitrosative stress (O/NS) and impaired neuroplasticity in schizophrenia are thought to have neurodevelopmental origins. Animal models are not only useful to test this hypothesis, they are also effective to establish a relationship among brain disturbances and behavior with the atypical antipsychotics (AAPs) effects. Here we review data of PFC post-mortem and in vivo neuroimaging, human induced pluripotent stem cells (hiPSC), and peripheral blood studies of inflammatory, O/NS, and neuroplasticity alterations in the disease as well as about their modulation by AAPs. Moreover, we reviewed the PFC alterations and the AAP mechanisms beyond their canonical antipsychotic action in four neurodevelopmental animal models relevant to the study of schizophrenia with a distinct approach in the generation of schizophrenia-like phenotypes, but all converge in O/NS and altered neuroplasticity in the PFC. These animal models not only reinforce the neurodevelopmental risk factor model of schizophrenia but also arouse some novel potential therapeutic targets for the disease including the reestablishment of the antioxidant response by the perineuronal nets (PNNs) and the nuclear factor erythroid 2-related factor (Nrf2) pathway, as well as the dendritic spine dynamics in the PFC pyramidal cells.
Collapse
Affiliation(s)
- Hiram Tendilla-Beltrán
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Mexico; Escuela Nacional de Ciencias Biológicas (ENCB), Instituto Politécnico Nacional (IPN), CDMX, Mexico
| | | | - Mauricio Marina-Ramos
- Departamento de Ciencias de la Salud, Universidad Popular Autónoma del Estado de Puebla, Puebla, Mexico
| | - Juan C Leza
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto Universitario de Investigación en Neuroquímica (IUIN), UCM. Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Investigación Sanitaria Hospital, 12 de Octubre (Imas12), Madrid, Spain
| | - Gonzalo Flores
- Instituto de Fisiología, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla, Mexico.
| |
Collapse
|
8
|
Post-translational protein modifications in schizophrenia. NPJ SCHIZOPHRENIA 2020; 6:5. [PMID: 32123175 PMCID: PMC7051976 DOI: 10.1038/s41537-020-0093-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 01/09/2020] [Indexed: 12/13/2022]
Abstract
Research investigating the pathophysiology of schizophrenia has not yet precisely defined the molecular phenotype of this disorder. Many studies have investigated cellular dysfunction by examining expression levels of molecular targets in postmortem patient brain; however, inconsistencies between transcript and protein measures in schizophrenia are common in the field and represent a challenge to the identification of a unified model of schizophrenia pathogenesis. In humans, >4800 unique proteins are expressed, and the majority of these are modified by glycans and/or lipids. Estimates indicate ~70% of all eukaryotic proteins are modified by at least one type of glycosylation, while nearly 20% of all proteins are known to be lipid-modified. Protein post-translational modification (PTM) by glycosylation and lipidation rely on the spatiotemporal colocalization of enzyme, substrate, and glycan or lipid donor molecule and do not require an upstream “blueprint” or specialized processing machinery for synthesis. Glycan and lipid PTMs can thus facilitate cellular adaptation to environmental signals more rapidly than changes of gene or protein expression, and can significantly impact the localization, function, and interactions of modified substrates, though relatively few studies in schizophrenia have evaluated the PTM status of target proteins. A growing body of literature reports glycosylation and lipidation abnormalities in schizophrenia brain as well as in patient peripheral fluids. In this review, we explain the functional significance of key glycan and lipid PTMs and summarize current findings associated with abnormal glycosylation and lipidation in this illness.
Collapse
|
9
|
Pinner AL, Mueller TM, Alganem K, McCullumsmith R, Meador-Woodruff JH. Protein expression of prenyltransferase subunits in postmortem schizophrenia dorsolateral prefrontal cortex. Transl Psychiatry 2020; 10:3. [PMID: 32066669 PMCID: PMC7026430 DOI: 10.1038/s41398-019-0610-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 09/09/2019] [Accepted: 10/03/2019] [Indexed: 12/22/2022] Open
Abstract
The pathophysiology of schizophrenia includes altered neurotransmission, dysregulated intracellular signaling pathway activity, and abnormal dendritic morphology that contribute to deficits of synaptic plasticity in the disorder. These processes all require dynamic protein-protein interactions at cell membranes. Lipid modifications target proteins to membranes by increasing substrate hydrophobicity by the addition of a fatty acid or isoprenyl moiety, and recent evidence suggests that dysregulated posttranslational lipid modifications may play a role in multiple neuropsychiatric disorders, including schizophrenia. Consistent with these emerging findings, we have recently reported decreased protein S-palmitoylation in schizophrenia. Protein prenylation is a lipid modification that occurs upstream of S-palmitoylation on many protein substrates, facilitating membrane localization and activity of key intracellular signaling proteins. Accordingly, we hypothesized that, in addition to palmitoylation, protein prenylation may be abnormal in schizophrenia. To test this, we assayed protein expression of the five prenyltransferase subunits (FNTA, FNTB, PGGT1B, RABGGTA, and RABGGTB) in postmortem dorsolateral prefrontal cortex from patients with schizophrenia and paired comparison subjects (n = 13 pairs). We found decreased levels of FNTA (14%), PGGT1B (13%), and RABGGTB (8%) in schizophrenia. To determine whether upstream or downstream factors may be driving these changes, we also assayed protein expression of the isoprenoid synthases FDPS and GGPS1 and prenylation-dependent processing enzymes RCE and ICMT. We found these upstream and downstream enzymes to have normal protein expression. To rule out effects from chronic antipsychotic treatment, we assayed FNTA, PGGT1B, and RABGGTB in the cortex from rats treated long-term with haloperidol decanoate and found no change in the expression of these proteins. Given the role prenylation plays in localization of key signaling proteins found at the synapse, these data offer a potential mechanism underlying abnormal protein-protein interactions and protein localization in schizophrenia.
Collapse
Affiliation(s)
- Anita L Pinner
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA.
| | - Toni M Mueller
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA
| | - Khaled Alganem
- Department of Neurosciences, University of Toledo, Toledo, OH, 43614-2598, USA
| | | | - James H Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA
| |
Collapse
|
10
|
Dysbindin-1 contributes to prefrontal cortical dendritic arbor pathology in schizophrenia. Schizophr Res 2018; 201:270-277. [PMID: 29759351 PMCID: PMC6230503 DOI: 10.1016/j.schres.2018.04.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 04/20/2018] [Accepted: 04/29/2018] [Indexed: 01/22/2023]
Abstract
Deep layer III pyramidal cells in the dorsolateral prefrontal cortex (DLPFC) from subjects with schizophrenia and bipolar disorder previously were shown to exhibit dendritic arbor pathology. This study sought to determine whether MARCKS, its regulatory protein dysbindin-1, and two proteins, identified using microarray data, CDC42BPA and ARHGEF6, were associated with dendritic arbor pathology in the DLPFC from schizophrenia and bipolar disorder subjects. Using western blotting, relative protein expression was assessed in the DLPFC (BA 46) grey matter from subjects with schizophrenia (n = 19), bipolar disorder (n = 17) and unaffected control subjects (n = 19). Protein expression data were then correlated with dendritic parameter data obtained previously. MARCKS and dysbindin-1a expression levels did not differ among the three groups. Dysbindin-1b expression was 26% higher in schizophrenia subjects (p = 0.01) and correlated inversely with basilar dendrite length (r = -0.31, p = 0.048) and the number of spines per basilar dendrite (r = -0.31, p = 0.048), but not with dendritic spine density (r = -0.16, p = 0.32). The protein expression of CDC42BPA was 33% higher in schizophrenia subjects (p = 0.03) but, did not correlate with any dendritic parameter (p > 0.05). ARHGEF6 87 kDa isoform expression did not differ among the groups. CDC42BPA expression was not altered in frontal cortex from rats chronically administered haloperidol or clozapine. Dysbindin-1b appears to play a role in dendritic arbor pathology observed previously in the DLPFC in schizophrenia.
Collapse
|
11
|
Velásquez E, Nogueira FCS, Velásquez I, Schmitt A, Falkai P, Domont GB, Martins-de-Souza D. Synaptosomal Proteome of the Orbitofrontal Cortex from Schizophrenia Patients Using Quantitative Label-Free and iTRAQ-Based Shotgun Proteomics. J Proteome Res 2017; 16:4481-4494. [PMID: 28949146 DOI: 10.1021/acs.jproteome.7b00422] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Schizophrenia is a chronic and incurable neuropsychiatric disorder that affects about one percent of the world population. The proteomic characterization of the synaptosome fraction of the orbitofrontal cortex is useful for providing valuable information about the molecular mechanisms of synaptic functions in these patients. Quantitative analyses of synaptic proteins were made with eight paranoid schizophrenia patients and a pool of eight healthy controls free of mental diseases. Label-free and iTRAQ labeling identified a total of 2018 protein groups. Statistical analyses revealed 12 and 55 significantly dysregulated proteins by iTRAQ and label-free, respectively. Quantitative proteome analyses showed an imbalance in the calcium signaling pathway and proteins such as reticulon-1 and cytochrome c, related to endoplasmic reticulum stress and programmed cell death. Also, it was found that there is a significant increase in limbic-system-associated membrane protein and α-calcium/calmodulin-dependent protein kinase II, associated with the regulation of human behavior. Our data contribute to a better understanding about apoptosis as a possible pathophysiological mechanism of this disease as well as neural systems supporting social behavior in schizophrenia. This study also is a joint effort of the Chr 15 C-HPP team and the Human Brain Proteome Project of B/D-HPP. All MS proteomics data are deposited in the ProteomeXchange Repository under PXD006798.
Collapse
Affiliation(s)
- Erika Velásquez
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro , Rio de Janeiro, 21941-909 Rio de Janeiro, Brazil
| | - Fabio C S Nogueira
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro , Rio de Janeiro, 21941-909 Rio de Janeiro, Brazil.,Laboratory of Proteomics, LADETEC, Institute of Chemistry, Federal University of Rio de Janeiro , Rio de Janeiro, 21941-598 Rio de Janeiro, Brazil
| | | | - Andrea Schmitt
- Department of Psychiatry and Psychotherapy, Ludwig Maximilian University of Munich (LMU) , 80336 Munich, Germany
| | - Peter Falkai
- Department of Psychiatry and Psychotherapy, Ludwig Maximilian University of Munich (LMU) , 80336 Munich, Germany
| | - Gilberto B Domont
- Proteomics Unit, Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro , Rio de Janeiro, 21941-909 Rio de Janeiro, Brazil
| | - Daniel Martins-de-Souza
- Laboratory of Neuroproteomics, Department of Biochemistry, Institute of Biology, University of Campinas (UNICAMP) , Campinas, 13083-862 São Paulo, Brazil.,UNICAMP's Neurobiology Center , Campinas, 13083-888 São Paulo, Brazil.,Instituto Nacional de Biomarcadores em Neuropsiquiatria (INBION), Conselho Nacional de Desenvolvimento Cientifico e Tecnologico , São Paulo, 01060-970 São Paulo, Brazil
| |
Collapse
|
12
|
Funk AJ, Mielnik CA, Koene R, Newburn E, Ramsey AJ, Lipska BK, McCullumsmith RE. Postsynaptic Density-95 Isoform Abnormalities in Schizophrenia. Schizophr Bull 2017; 43:891-899. [PMID: 28126896 PMCID: PMC5472126 DOI: 10.1093/schbul/sbw173] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Postsynaptic density-95 (PSD-95) protein expression is dysregulated in schizophrenia in a variety of brain regions. We have designed experiments to examine PSD-95 mRNA splice variant expression in the dorsolateral prefrontal cortex from subjects with schizophrenia. METHODS We performed quantitative PCR and western blot analysis to measure PSD-95 expression in schizophrenia vs control subjects, rodent haloperidol treatment studies, rodent postmortem interval studies, and GluN1 knockdown (KD) mice vs controls. RESULTS We found decreased mRNA expression of beta (t = 4.506, df = 383, P < .0001) and truncated (t = 3.378, df = 383, P = .0008) isoforms of PSD-95, whereas alpha was unchanged. Additionally, we found decreased PSD-95 protein expression in schizophrenia (t = 2.746, df = 71, P = .0076). We found no correlation between PSD-95 protein and alpha, beta, or truncated mRNA isoforms in schizophrenia. PSD-95 beta transcript was increased (t = 3.346, df = 14, P < .05) in the GluN1 KD mouse model of schizophrenia. There was an increase in PSD-95 alpha mRNA expression (t = 2.905, df = 16, P < .05) in rats following long-term haloperidol administration. CONCLUSIONS Our findings describe a unique pathophysiology of specific PSD-95 isoform dysregulation in schizophrenia, chronic neuroleptic treatment, and a genetic lesion mouse model of drastically reduced N-methyl-d-aspartate receptor (NMDAR) complex expression. These data indicate that regulation of PSD-95 is multifaceted, may be isoform specific, and biologically relevant for synaptic signaling function. Specifically, NMDAR-mediated synaptic remodeling, and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor trafficking and interaction may be impaired in schizophrenia by decreased PSD-95 beta and truncated expression (respectively). Further, increased PSD-95 beta transcript in the GluN1 KD mouse model poses a potential compensatory rescue of NMDAR-mediated function via increased postsynaptic throughput of the severely reduced GluN1 signal. Together, these data propose that disruption of excitatory signaling complexes through genetic (GluN1 KD), pharmacologic (antipsychotics), or disease (schizophrenia) mechanisms specifically dysregulates PSD-95 expression.
Collapse
Affiliation(s)
- Adam J. Funk
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Catharine A. Mielnik
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Rachael Koene
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH
| | | | - Amy J. Ramsey
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Barbara K. Lipska
- Human Brain Collection Core, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Bethesda, MD,Co-senior authors
| | - Robert E. McCullumsmith
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, OH;,Co-senior authors
| |
Collapse
|
13
|
Abstract
Schizophrenia is a severe psychiatric disorder that is characterized by a wide array of symptoms and a complex neuropathology. A well-characterized neurobiological feature of schizophrenia is abnormal synaptic plasticity, although the mechanisms underlying this are not fully understood. Numerous studies have demonstrated a link between proper functioning of the cytoskeleton and synaptic plasticity. The actin-related protein-2/3 (Arp2/3) complex is responsible for the nucleation of new actin filaments and elongation of existing actin filaments and is thus crucial to cytoskeletal dynamics, especially actin polymerization and organization. To determine whether the Arp2/3 complex is abnormally expressed in schizophrenia, we measured the protein expression of Arp2 and Arp3, as well as Arp2/3 complex binding partners and associated proteins including cortactin, neuronal-Wiskott-Aldrich syndrome protein (WASP), WASP-family verprolin homologous protein 1 (WAVE1), and Abelson interactor 1 (Abi1) in the superior temporal gyrus of paired schizophrenia and comparison participants. No changes were found in Arp2, Arp3, neuronal-WASP, WAVE1, or Abi1. However, all three isoforms of cortactin were decreased in schizophrenia. Specifically, the 62 kDa isoform was decreased by 43%; the 71 kDa isoform was decreased by 32%; and the 58 kDa isoform was decreased by 35%. Cortactin regulates branching of filamentous actin through its binding and activation of the Arp2/3 complex, and it is thus critical to the formation of stable actin networks. These findings contribute to a growing body of evidence implicating altered cytoskeletal dynamics in schizophrenia.
Collapse
|
14
|
Mubarik A, Tohid H. Frontal lobe alterations in schizophrenia: a review. TRENDS IN PSYCHIATRY AND PSYCHOTHERAPY 2016; 38:198-206. [DOI: 10.1590/2237-6089-2015-0088] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 05/20/2016] [Indexed: 12/16/2022]
Abstract
Abstract Objective: To highlight the changes in the frontal lobe of the human brain in people with schizophrenia. Methods: This was a qualitative review of the literature. Results: Many schizophrenic patients exhibit functional, structural, and metabolic abnormalities in the frontal lobe. Some patients have few or no alterations, while some have more functional and structural changes than others. Magnetic resonance imaging (MRI) shows structural and functional changes in volume, gray matter, white matter, and functional activity in the frontal lobe, but the mechanisms underlying these changes are not yet fully understood. Conclusion: When schizophrenia is studied as an essential topic in the field of neuropsychiatry, neuroscientists find that the frontal lobe is the most commonly involved area of the human brain. A clear picture of how this lobe is affected in schizophrenia is still lacking. We therefore recommend that further research be conducted to improve understanding of the pathophysiology of this psychiatric dilemma.
Collapse
|
15
|
Pinner AL, Tucholski J, Haroutunian V, McCullumsmith RE, Meador-Woodruff JH. Decreased protein S-palmitoylation in dorsolateral prefrontal cortex in schizophrenia. Schizophr Res 2016; 177:78-87. [PMID: 26876311 PMCID: PMC4981568 DOI: 10.1016/j.schres.2016.01.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/25/2016] [Accepted: 01/29/2016] [Indexed: 11/28/2022]
Abstract
Recent reports suggest abnormalities of neurotransmitter receptor trafficking, targeting, dendritic localization, recycling, and degradation in the brain in schizophrenia. We hypothesized that a potential explanation for these findings may be abnormal posttranslational modifications that influence intracellular targeting and trafficking of proteins between subcellular compartments. Dysregulation of protein palmitoylation is a strong candidate for such a process. S-palmitoylation is a reversible thioesterification of palmitoyl-groups to cysteine residues that can regulate trafficking and targeting of intracellular proteins. Using a biotin switch assay to study S-palmitoylation of proteins in human postmortem brain, we identified a pattern of palmitoylated proteins that cluster into 17 bands of discrete molecular masses, including numerous proteins associated with receptor signal transduction. Using mass spectrometry, we identified 219 palmitoylated proteins in human frontal cortex, and individually validated palmitoylation status of a subset of these proteins. Next, we assayed protein palmitoylation in dorsolateral prefrontal cortex from 16 schizophrenia patients and paired comparison subjects. S-palmitoylation was significantly reduced for proteins in most of the 17 schizophrenia bands. In rats chronically treated with haloperidol, the same pattern of palmitoylation was observed but the extent of palmitoylation was unchanged, suggesting that the diminution in protein palmitoylation in schizophrenia is not due to chronic antipsychotic treatment. These results indicate there are changes in the extent of S-palmitoylation of many proteins in the frontal cortex in schizophrenia. Given the roles of this posttranslational modification, these data suggest a potential mechanism reconciling previous observations of abnormal intracellular targeting and trafficking of neurotransmitter receptors in this illness.
Collapse
Affiliation(s)
- Anita L. Pinner
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA
| | - Janusz Tucholski
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA
| | - Vahram Haroutunian
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York, USA
| | - Robert E. McCullumsmith
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH 45219 USA
| | - James H. Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, 35294-0021, USA
| |
Collapse
|
16
|
Brudvig JJ, Weimer JM. X MARCKS the spot: myristoylated alanine-rich C kinase substrate in neuronal function and disease. Front Cell Neurosci 2015; 9:407. [PMID: 26528135 PMCID: PMC4602126 DOI: 10.3389/fncel.2015.00407] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 09/25/2015] [Indexed: 11/18/2022] Open
Abstract
Intracellular protein-protein interactions are dynamic events requiring tightly regulated spatial and temporal checkpoints. But how are these spatial and temporal cues integrated to produce highly specific molecular response patterns? A helpful analogy to this process is that of a cellular map, one based on the fleeting localization and activity of various coordinating proteins that direct a wide array of interactions between key molecules. One such protein, myristoylated alanine-rich C-kinase substrate (MARCKS) has recently emerged as an important component of this cellular map, governing a wide variety of protein interactions in every cell type within the brain. In addition to its well-documented interactions with the actin cytoskeleton, MARCKS has been found to interact with a number of other proteins involved in processes ranging from intracellular signaling to process outgrowth. Here, we will explore these diverse interactions and their role in an array of brain-specific functions that have important implications for many neurological conditions.
Collapse
Affiliation(s)
- Jon J Brudvig
- Children's Health Research Center, Sanford Research Sioux Falls, SD, USA ; Basic Biomedical Sciences, University of South Dakota Vermillion, SD, USA
| | - Jill M Weimer
- Children's Health Research Center, Sanford Research Sioux Falls, SD, USA ; Department of Pediatrics, Sanford School of Medicine, University of South Dakota Vermillion, SD, USA
| |
Collapse
|
17
|
Kippe JM, Mueller TM, Haroutunian V, Meador-Woodruff JH. Abnormal N-acetylglucosaminyltransferase expression in prefrontal cortex in schizophrenia. Schizophr Res 2015; 166:219-24. [PMID: 26104473 PMCID: PMC4512847 DOI: 10.1016/j.schres.2015.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/04/2015] [Accepted: 06/06/2015] [Indexed: 12/22/2022]
Abstract
Changes in the extent of the posttranslational modification glycosylation have been previously reported in several brain regions in schizophrenia. Quality control within the endoplasmic reticulum and Golgi, branching of glycans, intracellular trafficking and targeting, protein-protein interactions, and endocytosis are processes regulated by both N-linked and O-linked glycosylation. Previous studies in schizophrenia have found altered glycan biosynthesis and abnormal glycan levels in cerebrospinal fluid (CSF) and plasma, as well as altered expression in frontal cortex of glycosyltransferase transcripts encoding proteins associated with both N- and O-linked glycosylation. The N-acetylglucosaminyltransferases (GlcNAcTs) are glycosylating enzymes that play a key role in adding N-acetylglucosamine (GlcNAc) to substrates to facilitate their proper trafficking, intracellular targeting, and cellular function. Given previous results indicating abnormal glycosylation in schizophrenia, we hypothesized that these GlcNAcTs may be abnormally expressed in this illness. We measured protein expression of nine distinct GlcNAcTs by Western blot analysis in postmortem samples of dorsolateral prefrontal cortex (DLPFC) from twelve pairs of elderly patients with schizophrenia and comparison subjects. We found decreased protein expression of UDP-GlcNAc:BetaGal Beta-1,3 GlcNAcT 8 (B3GNT8) and mannosyl (alpha-1,3-)-glycoprotein beta-1,4 GlcNAcT (MGAT4A) expression in schizophrenia. These data provide further evidence that glycosylation is dysregulated in schizophrenia, and suggest a potential mechanism associated with alterations in protein function, trafficking, and intracellular targeting in this illness.
Collapse
Affiliation(s)
- Jordyn M Kippe
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA.
| | - Toni M Mueller
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA
| | - Vahram Haroutunian
- Department of Psychiatry, Mount Sinai School of Medicine, New York, NY USA
| | - James H Meador-Woodruff
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL USA
| |
Collapse
|
18
|
Konopaske GT, Subburaju S, Coyle JT, Benes FM. Altered prefrontal cortical MARCKS and PPP1R9A mRNA expression in schizophrenia and bipolar disorder. Schizophr Res 2015; 164:100-8. [PMID: 25757715 PMCID: PMC4409526 DOI: 10.1016/j.schres.2015.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 12/18/2022]
Abstract
BACKGROUND We previously observed dendritic spine loss in the dorsolateral prefrontal cortex (DLPFC) from schizophrenia and bipolar disorder subjects. In the current study, we sought to determine if the mRNA expression of genes known to regulate the actin cytoskeleton and spines correlated with spine loss. METHODS Five candidate genes were identified using previously obtained microarray data from the DLPFC from schizophrenia and control subjects. The relative mRNA expression of the genes linked to dendritic spine growth and function, i.e. IGF1R, MARCKS, PPP1R9A, PTPRF, and ARHGEF2, was assessed using quantitative real-time PCR (qRT-PCR) in the DLPFC from a second cohort including schizophrenia, bipolar disorder, and control subjects. Functional pathway analysis was conducted to determine which actin cytoskeleton-regulatory pathways the genes of interest interact with. RESULTS MARCKS mRNA expression was increased in both schizophrenia and bipolar disorder subjects. PPP1R9A mRNA expression was increased in bipolar disorder subjects. For IGF1R, mRNA expression did not differ significantly among groups; however, it did show a significant, negative correlation with dendrite length. MARCKS and PPP1R9A mRNA expression did not correlate with spine loss, but they interact with NMDA receptor signaling pathways that regulate the actin cytoskeleton and spines. CONCLUSIONS MARCKS and PPP1R9A might contribute to spine loss in schizophrenia and bipolar disorder through their interactions, possibly indirect ones, with NMDA signaling pathways that regulate spine structure and function.
Collapse
Affiliation(s)
- Glenn T. Konopaske
- Mailman Research Center, McLean Hospital, Belmont, MA, USA, Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Sivan Subburaju
- Mailman Research Center, McLean Hospital, Belmont, MA, USA, Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Joseph T. Coyle
- Mailman Research Center, McLean Hospital, Belmont, MA, USA, Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Francine M. Benes
- Mailman Research Center, McLean Hospital, Belmont, MA, USA, Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| |
Collapse
|