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Lin W, Phatarphekar A, Zhong Y, Liu L, Kwon HB, Gerwick WH, Wang Y, Mehta S, Zhang J. Light-gated Integrator for Highlighting Kinase Activity in Living Cells. bioRxiv 2024:2024.03.18.585554. [PMID: 38562887 PMCID: PMC10983958 DOI: 10.1101/2024.03.18.585554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Protein kinases are key signaling nodes that regulate fundamental biological and disease processes. Illuminating kinase signaling from multiple angles can provide deeper insights into disease mechanisms and improve therapeutic targeting. While fluorescent biosensors are powerful tools for visualizing live-cell kinase activity dynamics in real time, new molecular tools are needed that enable recording of transient signaling activities for post hoc analysis and targeted manipulation. Here, we develop a light-gated kinase activity coupled transcriptional integrator (KINACT) that converts dynamic kinase signals into "permanent" fluorescent marks. KINACT enables robust monitoring of kinase activity across scales, accurately recording subcellular PKA activity, highlighting PKA signaling heterogeneity in 3D cultures, and identifying PKA activators and inhibitors in high-throughput screens. We further leverage the ability of KINACT to drive signaling effector expression to allow feedback manipulation of the balance of GαsR201C-induced PKA and ERK activation and dissect the mechanisms of oncogenic G protein signaling.
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Affiliation(s)
- Wei Lin
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
| | | | - Yanghao Zhong
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
| | - Longwei Liu
- Alfred E. Mann Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - William H. Gerwick
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Yingxiao Wang
- Alfred E. Mann Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
| | - Jin Zhang
- Department of Pharmacology, University of California San Diego, La Jolla, CA, USA
- Moores Cancer Center, University of California San Diego, La Jolla, CA, USA
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
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2
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Cui M, Lee S, Ban SH, Ryu JR, Shen M, Yang SH, Kim JY, Choi SK, Han J, Kim Y, Han K, Lee D, Sun W, Kwon HB, Lee D. A single-component, light-assisted uncaging switch for endoproteolytic release. Nat Chem Biol 2024; 20:353-364. [PMID: 37973890 DOI: 10.1038/s41589-023-01480-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 10/12/2023] [Indexed: 11/19/2023]
Abstract
Proteases function as pivotal molecular switches, initiating numerous biological events. Notably, potyviral protease, derived from plant viruses, has emerged as a trusted proteolytic switch in synthetic biological circuits. To harness their capabilities, we have developed a single-component photocleavable switch, termed LAUNCHER (Light-Assisted UNcaging switCH for Endoproteolytic Release), by employing a circularly permutated tobacco etch virus protease and a blue-light-gated substrate, which are connected by fine-tuned intermodular linkers. As a single-component system, LAUNCHER exhibits a superior signal-to-noise ratio compared with multi-component systems, enabling precise and user-controllable release of payloads. This characteristic renders LAUNCHER highly suitable for diverse cellular applications, including transgene expression, tailored subcellular translocation and optochemogenetics. Additionally, the plug-and-play integration of LAUNCHER into existing synthetic circuits facilitates the enhancement of circuit performance. The demonstrated efficacy of LAUNCHER in improving existing circuitry underscores its significant potential for expanding its utilization in various applications.
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Affiliation(s)
- Mingguang Cui
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Seunghwan Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Sung Hwan Ban
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jae Ryun Ryu
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Meiying Shen
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Soo Hyun Yang
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jin Young Kim
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
| | - Seul Ki Choi
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jaemin Han
- Korea University College of Medicine, Seoul, Republic of Korea
| | - Yoonhee Kim
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Kihoon Han
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
- Department of Neuroscience, Korea University College of Medicine, Seoul, Republic of Korea
| | - Donghun Lee
- Department of Physics, Korea University, Seoul, Republic of Korea
| | - Woong Sun
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dongmin Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea.
- BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea.
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3
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Son S, Nagahama K, Lee J, Jung K, Kwak C, Kim J, Noh YW, Kim E, Lee S, Kwon HB, Heo WD. Real-time visualization of structural dynamics of synapses in live cells in vivo. Nat Methods 2024; 21:353-360. [PMID: 38191933 DOI: 10.1038/s41592-023-02122-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 11/01/2023] [Indexed: 01/10/2024]
Abstract
The structural plasticity of synapses is crucial for regulating brain functions. However, currently available methods for studying synapse organization based on split fluorescent proteins (FPs) have been limited in assessing synaptic dynamics in vivo due to the irreversible binding of split FPs. Here, we develop 'SynapShot', a method for visualizing the structural dynamics of intact synapses by combining dimerization-dependent FPs (ddFPs) with engineered synaptic adhesion molecules. SynapShot allows real-time monitoring of reversible and bidirectional changes of synaptic contacts under physiological stimulation. The application of green and red ddFPs in SynapShot enables simultaneous visualization of two distinct populations of synapses. Notably, the red-shifted SynapShot is highly compatible with blue light-based optogenetic techniques, allowing for visualization of synaptic dynamics while precisely controlling specific signaling pathways. Furthermore, we demonstrate that SynapShot enables real-time monitoring of structural changes in synaptic contacts in the mouse brain during both primitive and higher-order behaviors.
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Affiliation(s)
- Seungkyu Son
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Kenichiro Nagahama
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jinsu Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Kanghoon Jung
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
- Allen Institute for Neural Dynamics, Seattle, WA, USA
| | - Chuljung Kwak
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jihoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Young Woo Noh
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Eunjoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, Republic of Korea
| | - Sangkyu Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea.
| | - Hyung-Bae Kwon
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Won Do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
- KAIST Institute for the BioCentury, KAIST, Daejeon, Republic of Korea.
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Roh SE, Xiao M, Delgado A, Kwak C, Savonenko A, Bakker A, Kwon HB, Worley P. Sleep and circadian rhythm disruption by NPTX2 loss of function. bioRxiv 2023:2023.09.26.559408. [PMID: 37808783 PMCID: PMC10557648 DOI: 10.1101/2023.09.26.559408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Sleep and circadian rhythm disruption (SCRD) is commonly observed in aging, especially in individuals who experience progressive cognitive decline to mild cognitive impairment (MCI) and Alzheimer's disease (AD). However, precise molecular mechanisms underlying the association between SCRD and aging are not fully understood. Orexin A is a well-characterized "sleep neuropeptide" that is expressed in hypothalamic neurons and evokes wake behavior. The importance of Orexin is exemplified in narcolepsy where it is profoundly down-regulated. Interestingly, the synaptic immediate early gene NPTX2 is co-expressed in Orexin neurons and is similarly reduced in narcolepsy. NPTX2 is also down-regulated in CSF of some cognitively normal older individuals and predicts the time of transition from normal cognition to MCI. The association between Orexin and NPTX2 is further evinced here where we observe that Orexin A and NPTX2 are highly correlated in CSF of cognitively normal aged individuals and raises the question of whether SCRD that are typically attributed to Orexin A loss of function may be modified by concomitant NPTX2 down-regulation. Is NPTX2 an effector of sleep or simply a reporter of orexin-dependent SCRD? To address this question, we examined NPTX2 KO mice and found they retain Orexin expression in the brain and so provide an opportunity to examine the specific contribution of NPTX2 to SCRD. Our results reveal that NPTX2 KO mice exhibit a disrupted circadian onset time, coupled with increased activity during the sleep phase, suggesting difficulties in maintaining states. Sleep EEG indicates distinct temporal allocation shifts across vigilance states, characterized by reduced wake and increased NREM time. Evident sleep fragmentation manifests through alterations of event occurrences during Wake and NREM, notably during light transition periods, in conjunction with an increased frequency of sleep transitions in NPTX2 KO mice, particularly between Wake and NREM. EEG spectral analysis indicated significant shifts in power across various frequency bands in the wake, NREM, and REM states, suggestive of disrupted neuronal synchronicity. An intriguing observation is the diminished occurrence of sleep spindles, one of the earliest measures of human sleep disruption, in NPTX2 KO mice. These findings highlight the effector role of NPTX2 loss of function as an instigator of SCRD and a potential mediator of sleep disruption in aging.
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Affiliation(s)
- Seung-Eon Roh
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Meifang Xiao
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ana Delgado
- Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chuljung Kwak
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Alena Savonenko
- Department of Neuroanatomy, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Arnold Bakker
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Paul Worley
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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5
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Valtcheva S, Issa HA, Bair-Marshall CJ, Martin KA, Jung K, Zhang Y, Kwon HB, Froemke RC. Neural circuitry for maternal oxytocin release induced by infant cries. Nature 2023; 621:788-795. [PMID: 37730989 PMCID: PMC10639004 DOI: 10.1038/s41586-023-06540-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 08/15/2023] [Indexed: 09/22/2023]
Abstract
Oxytocin is a neuropeptide that is important for maternal physiology and childcare, including parturition and milk ejection during nursing1-6. Suckling triggers the release of oxytocin, but other sensory cues-specifically, infant cries-can increase the levels of oxytocin in new human mothers7, which indicates that cries can activate hypothalamic oxytocin neurons. Here we describe a neural circuit that routes auditory information about infant vocalizations to mouse oxytocin neurons. We performed in vivo electrophysiological recordings and photometry from identified oxytocin neurons in awake maternal mice that were presented with pup calls. We found that oxytocin neurons responded to pup vocalizations, but not to pure tones, through input from the posterior intralaminar thalamus, and that repetitive thalamic stimulation induced lasting disinhibition of oxytocin neurons. This circuit gates central oxytocin release and maternal behaviour in response to calls, providing a mechanism for the integration of sensory cues from the offspring in maternal endocrine networks to ensure modulation of brain state for efficient parenting.
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Affiliation(s)
- Silvana Valtcheva
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA.
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
| | - Habon A Issa
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Chloe J Bair-Marshall
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Kathleen A Martin
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA
- Center for Neural Science, New York University, New York, NY, USA
| | - Kanghoon Jung
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yiyao Zhang
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert C Froemke
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York, NY, USA.
- Neuroscience Institute, New York University School of Medicine, New York, NY, USA.
- Department of Otolaryngology, New York University School of Medicine, New York, NY, USA.
- Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
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6
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Jung K, Chang M, Steinecke A, Burke B, Choi Y, Oisi Y, Fitzpatrick D, Taniguchi H, Kwon HB. An adaptive behavioral control motif mediated by cortical axo-axonic inhibition. Nat Neurosci 2023; 26:1379-1393. [PMID: 37474640 PMCID: PMC10400431 DOI: 10.1038/s41593-023-01380-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 06/13/2023] [Indexed: 07/22/2023]
Abstract
Genetically defined subgroups of inhibitory interneurons are thought to play distinct roles in learning, but heterogeneity within these subgroups has limited our understanding of the scope and nature of their specific contributions. Here we reveal that the chandelier cell (ChC), an interneuron type that specializes in inhibiting the axon-initial segment (AIS) of pyramidal neurons, establishes cortical microcircuits for organizing neural coding through selective axo-axonic synaptic plasticity. We found that organized motor control is mediated by enhanced population coding of direction-tuned premotor neurons, with tuning refined through suppression of irrelevant neuronal activity. ChCs contribute to learning-dependent refinements by providing selective inhibitory control over individual pyramidal neurons rather than global suppression. Quantitative analysis of structural plasticity across axo-axonic synapses revealed that ChCs redistributed inhibitory weights to individual pyramidal neurons during learning. These results demonstrate an adaptive logic of the inhibitory circuit motif responsible for organizing distributed neural representations. Thus, ChCs permit efficient cortical computation in a targeted cell-specific manner.
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Affiliation(s)
- Kanghoon Jung
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
- Allen Institute for Neural Dynamics, Seattle, WA, USA
| | - Minhyeok Chang
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - André Steinecke
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
| | - Benjamin Burke
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Youngjin Choi
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yasuhiro Oisi
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
| | | | - Hiroki Taniguchi
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
- Department of Pathology, Chronic Brain Injury program, Ohio State University, Columbus, OH, USA
| | - Hyung-Bae Kwon
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA.
- Max Planck Institute of Neurobiology, Martinsried, Germany.
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Krüssel S, Deb I, Son S, Ewall G, Chang M, Lee HK, do Heo W, Kwon HB. Exuberant de novo dendritic spine growth in mature neurons. bioRxiv 2023:2023.07.21.550095. [PMID: 37546796 PMCID: PMC10401948 DOI: 10.1101/2023.07.21.550095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Dendritic spines are structural correlates of excitatory synapses maintaining stable synaptic communications. However, this strong spine-synapse relationship was mainly characterized in excitatory pyramidal neurons (PyNs), raising a possibility that inferring synaptic density from dendritic spine number may not be universally applied to all neuronal types. Here we found that the ectopic expression of H-Ras increased dendritic spine numbers regardless of cortical cell types such as layer 2/3 pyramidal neurons (PyNs), parvalbumin (PV)- and vasoactive intestinal peptide (VIP)-positive interneurons (INs) in the primary motor cortex (M1). The probability of detecting dendritic spines was positively correlated with the magnitude of H-Ras activity, suggesting elevated local H-Ras activity is involved in the process of dendritic spine formation. H-Ras overexpression caused high spine turnover rate via adding more spines rather than eliminating them. Two-photon photolysis of glutamate triggered de novo dendritic spine formation in mature neurons, suggesting H-Ras induced spine formation is not restricted to the early development. In PyNs and PV-INs, but not VIP-INs, we observed a shift in average spine neck length towards longer filopodia-like phenotypes. The portion of dendritic spines lacking key excitatory synaptic proteins were significantly increased in H-Ras transfected neurons, suggesting that these increased spines have other distinct functions. High spine density caused by H-Ras did not result in change in the frequency or the amplitude of miniature excitatory postsynaptic currents (mEPSCs). Thus, our results propose that dendritic spines possess more multifaceted functions beyond the morphological proxy of excitatory synapse.
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Affiliation(s)
- Sarah Krüssel
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ishana Deb
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Seungkyu Son
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Gabrielle Ewall
- Solomon H. Snyder Department of Neuroscience, Zanvyl-Krieger Mind/Brain Institute, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Minhyeok Chang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hey-Kyoung Lee
- Solomon H. Snyder Department of Neuroscience, Zanvyl-Krieger Mind/Brain Institute, Johns Hopkins School of Medicine, Baltimore, MD, United States
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, United States
| | - Won do Heo
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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8
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Jung K, Chang M, Steinecke A, Berke B, Choi Y, Oisi Y, Fitzpatrick D, Taniguchi H, Kwon HB. An adaptive behavioral control motif mediated by cortical axo-axonic inhibition. bioRxiv 2023:2023.03.10.531767. [PMID: 36945592 PMCID: PMC10029003 DOI: 10.1101/2023.03.10.531767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Neural circuits are reorganized with specificity during learning. Genetically-defined subgroups of inhibitory interneurons are thought to play distinct roles in learning, but heterogeneity within these subgroups has limited our understanding of the scope and nature of their specific contributions to learning. Here we reveal that the chandelier cell (ChC), an interneuron type that specializes in inhibiting the axon-initial segment (AIS) of pyramidal neurons, establishes cortical microcircuits for organizing neural coding through selective axo-axonic synaptic plasticity. We find that organized motor control is mediated by enhanced population coding of direction-tuned premotor neurons, whose tuning is refined through suppression of irrelevant neuronal activity. ChCs are required for learning-dependent refinements via providing selective inhibitory control over pyramidal neurons rather than global suppression. Quantitative analysis on structural plasticity of axo-axonic synapses revealed that ChCs redistributed inhibitory weights to individual pyramidal neurons during learning. These results demonstrate an adaptive logic of the inhibitory circuit motif responsible for organizing distributed neural representations. Thus, ChCs permit efficient cortical computation in a target cell specific manner, which highlights the significance of interneuron diversity.
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9
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Abstract
Cognitive flexibility is a brain's ability to switch between different rules or action plans depending on the context. However, cellular level understanding of cognitive flexibility have been largely unexplored. We probed a specific serotonergic pathway from dorsal raphe nuclei (DRN) to the orbitofrontal cortex (OFC) while animals are performing reversal learning task. We found that serotonin release from DRN to the OFC promotes reversal learning. A long-range connection between these two brain regions was confirmed anatomically and functionally. We further show that spatiotemporally precise serotonergic action directly enhances the excitability of OFC neurons and offers enhanced spike probability of OFC network. Serotonergic action facilitated the induction of synaptic plasticity by enhancing Ca2+ influx at dendritic spines in the OFC. Thus, our findings suggest that a key signature of flexibility is the formation of choice specific ensembles via serotonin-dependent synaptic plasticity.
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Affiliation(s)
- Jung Ho Hyun
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458, USA
- Department of Brain Sciences, DGIST, Daegu, Republic of Korea
| | - Patrick Hannan
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458, USA
| | - Hideki Iwamoto
- Department of Biomedical Science and Brain Institute, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Randy D. Blakely
- Department of Biomedical Science and Brain Institute, Charles E. Schmidt College of Medicine, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458, USA
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10
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Kwon HB. Writing cellular history in protein chains. Nat Biotechnol 2023; 41:617-618. [PMID: 36593409 DOI: 10.1038/s41587-022-01597-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Hyung-Bae Kwon
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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11
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Abstract
Various cortical functions arise from the dynamic interplay of excitation and inhibition. GABAergic interneurons that mediate synaptic inhibition display significant diversity in cell morphology, electrophysiology, plasticity rule, and connectivity. These heterogeneous features are thought to underlie their functional diversity. Emerging attention on specific properties of the various interneuron types has emphasized the crucial role of cell-type specific inhibition in cortical neural processing. However, knowledge is still limited on how each interneuron type forms distinct neural circuits and regulates network activity in health and disease. To dissect interneuron heterogeneity at single cell-type precision, we focus on the chandelier cell (ChC), one of the most distinctive GABAergic interneuron types that exclusively innervate the axon initial segments (AIS) of excitatory pyramidal neurons. Here we review the current understanding of the structural and functional properties of ChCs and their implications in behavioral functions, network activity, and psychiatric disorders. These findings provide insights into the distinctive roles of various single-type interneurons in cortical neural coding and the pathophysiology of cortical dysfunction.
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12
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Chang M, Lee OC, Bu G, Oh J, Yunn NO, Ryu SH, Kwon HB, Kolomeisky AB, Shim SH, Doh J, Jeon JH, Lee JB. Formation of cellular close-ended tunneling nanotubes through mechanical deformation. Sci Adv 2022; 8:eabj3995. [PMID: 35353579 PMCID: PMC8967236 DOI: 10.1126/sciadv.abj3995] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Membrane nanotubes or tunneling nanotubes (TNTs) that connect cells have been recognized as a previously unidentified pathway for intercellular transport between distant cells. However, it is unknown how this delicate structure, which extends over tens of micrometers and remains robust for hours, is formed. Here, we found that a TNT develops from a double filopodial bridge (DFB) created by the physical contact of two filopodia through helical deformation of the DFB. The transition of a DFB to a close-ended TNT is most likely triggered by disruption of the adhesion of two filopodia by mechanical energy accumulated in a twisted DFB when one of the DFB ends is firmly attached through intercellular cadherin-cadherin interactions. These studies pinpoint the mechanistic questions about TNTs and elucidate a formation mechanism.
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Affiliation(s)
- Minhyeok Chang
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - O-chul Lee
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Gayun Bu
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Jaeho Oh
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Na-Oh Yunn
- POSTECH Biotech Center, Pohang 37673, Korea
| | - Sung Ho Ryu
- Department of Life Sciences, POSTECH, Pohang 37673, Korea
| | - Hyung-Bae Kwon
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Sang-Hee Shim
- Department of Chemistry, Korea University, Seoul 02481, Korea
| | - Junsang Doh
- Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Korea
| | - Jae-Hyung Jeon
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
- Asia Pacific Center for Theoretical Physics (APCTP), Pohang 37673, Korea
- Corresponding author. (J.-B.L.); (J.-H.J.)
| | - Jong-Bong Lee
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
- Asia Pacific Center for Theoretical Physics (APCTP), Pohang 37673, Korea
- School of Interdisciplinary Bioscience and Bioengineering, POSTECH, Pohang 37673, Korea
- Corresponding author. (J.-B.L.); (J.-H.J.)
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13
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Lee D, Kwon HB. Current and future techniques for detecting oxytocin: Focusing on genetically-encoded GPCR sensors. J Neurosci Methods 2022; 366:109407. [PMID: 34763021 DOI: 10.1016/j.jneumeth.2021.109407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 10/12/2021] [Accepted: 11/03/2021] [Indexed: 10/19/2022]
Abstract
Oxytocin is a neuropituitary hormone that is involved in a wide range of psychosocial behaviors. Despite its psychophysiological importance as a neuromodulator in the CNS, effective techniques capable of monitoring oxytocin dynamics or testing related behavioral consequences are limited. Along with an explosive advancement in synthetic biology, high-performance genetically-encoded neuromodulator sensors are being developed. Here we comprehensively review the current methodologies available for detecting oxytocin in neuroscience. Their strengths and weaknesses are discussed, and a graphical summary is plotted for better comparison of techniques. We also suggest future directions for next generation oxytocin sensor development and their working principles.
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Affiliation(s)
- Dongmin Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Republic of Korea; BK21 Graduate Program, Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyung-Bae Kwon
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733N Broadway, Baltimore, MD 21205, USA.
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14
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Hayano Y, Ishino Y, Hyun JH, Orozco CG, Steinecke A, Potts E, Oisi Y, Thomas CI, Guerrero-Given D, Kim E, Kwon HB, Kamasawa N, Taniguchi H. IgSF11 homophilic adhesion proteins promote layer-specific synaptic assembly of the cortical interneuron subtype. Sci Adv 2021; 7:eabf1600. [PMID: 34261648 PMCID: PMC8279514 DOI: 10.1126/sciadv.abf1600] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 05/28/2021] [Indexed: 05/16/2023]
Abstract
The most prominent structural hallmark of the mammalian neocortical circuitry is the layer-based organization of specific cell types and synaptic inputs. Accordingly, cortical inhibitory interneurons (INs), which shape local network activity, exhibit subtype-specific laminar specificity of synaptic outputs. However, the underlying molecular mechanisms remain unknown. Here, we demonstrate that Immunoglobulin Superfamily member 11 (IgSF11) homophilic adhesion proteins are preferentially expressed in one of the most distinctive IN subtypes, namely, chandelier cells (ChCs) that specifically innervate axon initial segments of pyramidal neurons (PNs), and their synaptic laminar target. Loss-of-function experiments in either ChCs or postsynaptic cells revealed that IgSF11 is required for ChC synaptic development in the target layer. While overexpression of IgSF11 in ChCs enlarges ChC presynaptic boutons, expressing IgSF11 in nontarget layers induces ectopic ChC synapses. These findings provide evidence that synapse-promoting adhesion proteins, highly localized to synaptic partners, determine the layer-specific synaptic connectivity of the cortical IN subtype.
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Affiliation(s)
- Yasufumi Hayano
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Yugo Ishino
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Jung Ho Hyun
- Cellular Basis of Neural Circuit Plasticity, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Carlos G Orozco
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
- Electron Microscopy Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - André Steinecke
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Elizabeth Potts
- Electron Microscopy Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Yasuhiro Oisi
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Connon I Thomas
- Electron Microscopy Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Debbie Guerrero-Given
- Electron Microscopy Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Eunjoon Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science, Daejeon, South Korea
| | - Hyung-Bae Kwon
- Cellular Basis of Neural Circuit Plasticity, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Max Planck Institute for Neurobiology, Martinsried, Munich 82152, Germany
| | - Naomi Kamasawa
- Electron Microscopy Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Hiroki Taniguchi
- Development and Function of Inhibitory Neural Circuits, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA.
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15
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Lituma PJ, Kwon HB, Alviña K, Luján R, Castillo PE. Presynaptic NMDA receptors facilitate short-term plasticity and BDNF release at hippocampal mossy fiber synapses. eLife 2021; 10:e66612. [PMID: 34061025 PMCID: PMC8186907 DOI: 10.7554/elife.66612] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 05/28/2021] [Indexed: 01/12/2023] Open
Abstract
Neurotransmitter release is a highly controlled process by which synapses can critically regulate information transfer within neural circuits. While presynaptic receptors - typically activated by neurotransmitters and modulated by neuromodulators - provide a powerful way of fine-tuning synaptic function, their contribution to activity-dependent changes in transmitter release remains poorly understood. Here, we report that presynaptic NMDA receptors (preNMDARs) at mossy fiber boutons in the rodent hippocampus can be activated by physiologically relevant patterns of activity and selectively enhance short-term synaptic plasticity at mossy fiber inputs onto CA3 pyramidal cells and mossy cells, but not onto inhibitory interneurons. Moreover, preNMDARs facilitate brain-derived neurotrophic factor release and contribute to presynaptic calcium rise. Taken together, our results indicate that by increasing presynaptic calcium, preNMDARs fine-tune mossy fiber neurotransmission and can control information transfer during dentate granule cell burst activity that normally occur in vivo.
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Affiliation(s)
- Pablo J Lituma
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineBronxUnited States
| | - Hyung-Bae Kwon
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineBronxUnited States
| | - Karina Alviña
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineBronxUnited States
| | - Rafael Luján
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Facultad de Medicina, Universidad Castilla-La ManchaAlbaceteSpain
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of MedicineBronxUnited States
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of MedicineBronxUnited States
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16
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Beas BS, Wright BJ, Skirzewski M, Leng Y, Hyun JH, Koita O, Ringelberg N, Kwon HB, Buonanno A, Penzo MA. The locus coeruleus drives disinhibition in the midline thalamus via a dopaminergic mechanism. Nat Neurosci 2018; 21:963-973. [PMID: 29915192 PMCID: PMC6035776 DOI: 10.1038/s41593-018-0167-4] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/25/2018] [Indexed: 12/13/2022]
Abstract
The paraventricular nucleus of the thalamus (PVT) is increasingly being recognized as a critical node linking stress detection to the emergence of adaptive behavioral responses to stress. However, despite growing evidence implicating the PVT in stress processing, the neural mechanisms by which stress impacts PVT neurocircuitry and promotes stressed states remain unknown. Here we show that stress exposure drives a rapid and persistent reduction of inhibitory transmission onto projection neurons of the posterior PVT (pPVT). This stress-induced disinhibition of the pPVT was associated with a locus coeruleus (LC)-mediated rise in the extracellular concentration of dopamine in the midline thalamus, required the function of dopamine D2 receptors on PVT neurons and increased sensitivity to stress. Our findings define the LC as an important modulator of PVT function: by controlling the inhibitory tone of the pPVT, it modulates the excitability of pPVT projection neurons and controls stress responsivity.
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Affiliation(s)
- B Sofia Beas
- National Institute of Mental Health, Bethesda, MD, USA
| | | | - Miguel Skirzewski
- National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Yan Leng
- National Institute of Mental Health, Bethesda, MD, USA
| | - Jung Ho Hyun
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
| | - Omar Koita
- National Institute of Mental Health, Bethesda, MD, USA
| | | | - Hyung-Bae Kwon
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA.,Max Planck Institute of Neurobiology, Martinsried, Germany
| | - Andres Buonanno
- National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Mario A Penzo
- National Institute of Mental Health, Bethesda, MD, USA.
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17
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Lee D, Hyun JH, Jung K, Hannan P, Kwon HB. A calcium- and light-gated switch to induce gene expression in activated neurons. Nat Biotechnol 2017. [DOI: 10.1038/nbt.3902] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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18
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Oh WC, Lutzu S, Castillo PE, Kwon HB. De novo synaptogenesis induced by GABA in the developing mouse cortex. Science 2016; 353:1037-1040. [PMID: 27516412 DOI: 10.1126/science.aaf5206] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 08/03/2016] [Indexed: 12/23/2022]
Abstract
Dendrites of cortical pyramidal neurons contain intermingled excitatory and inhibitory synapses. We studied the local mechanisms that regulate the formation and distribution of synapses. We found that local γ-aminobutyric acid (GABA) release on dendrites of mouse cortical layer 2/3 pyramidal neurons could induce gephyrin puncta and dendritic spine formation via GABA type A receptor activation and voltage-gated calcium channels during early postnatal development. Furthermore, the newly formed inhibitory and excitatory synaptic structures rapidly gained functions. Bidirectional manipulation of GABA release from somatostatin-positive interneurons increased and decreased the number of gephyrin puncta and dendritic spines, respectively. These results highlight a noncanonical function of GABA as a local synaptogenic element shaping the early establishment of neuronal circuitry in mouse cortex.
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Affiliation(s)
- Won Chan Oh
- Max Planck Florida Institute for Neuroscience (MPFI), Jupiter, FL 33458, USA
| | - Stefano Lutzu
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Pablo E Castillo
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Hyung-Bae Kwon
- Max Planck Florida Institute for Neuroscience (MPFI), Jupiter, FL 33458, USA. Max Planck Institute of Neurobiology, Martinsried 82152, Germany.
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19
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Kantevari S, Passlick S, Kwon HB, Richers MT, Sabatini BL, Ellis-Davies GCR. Development of Anionically Decorated Caged Neurotransmitters: In Vitro Comparison of 7-Nitroindolinyl- and 2-(p-Phenyl-o-nitrophenyl)propyl-Based Photochemical Probes. Chembiochem 2016; 17:953-61. [PMID: 26929152 DOI: 10.1002/cbic.201600019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Indexed: 01/26/2023]
Abstract
Neurotransmitter uncaging, especially that of glutamate, has been used to study synaptic function for over 30 years. One limitation of caged glutamate probes is the blockade of γ-aminobutyric acid (GABA)-A receptor function. This problem comes to the fore when the probes are applied at the high concentrations required for effective two-photon photolysis. To mitigate such problems one could improve the photochemical properties of caging chromophores and/or remove receptor blockade. We show that addition of a dicarboxylate unit to the widely used 4-methoxy-7-nitroindolinyl-Glu (MNI-Glu) system reduced the off-target effects by about 50-70 %. When the same strategy was applied to an electron-rich 2-(p-Phenyl-o-nitrophenyl)propyl (PNPP) caging group, the pharmacological improvements were not as significant as in the MNI case. Finally, we used very extensive biological testing of the PNPP-caged Glu (more than 250 uncaging currents at single dendritic spines) to show that nitro-biphenyl caging chromophores have two-photon uncaging efficacies similar to that of MNI-Glu.
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Affiliation(s)
- Srinivas Kantevari
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029, USA) graham.davies at mssm.edu.,Organic Chemistry Division II (CPC Division), CSIR-Indian Institute of Chemical Technology, Hyderabad, 500 007, India
| | - Stefan Passlick
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029, USA) graham.davies at mssm.edu
| | - Hyung-Bae Kwon
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Cambridge, MA, 02115, USA.,Max Planck Florida Institute for Neuroscience, Jupiter, FL, 33458, USA
| | - Matthew T Richers
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029, USA) graham.davies at mssm.edu
| | - Bernardo L Sabatini
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Cambridge, MA, 02115, USA
| | - Graham C R Ellis-Davies
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029, USA) graham.davies at mssm.edu
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20
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Villa KL, Berry KP, Subramanian J, Cha JW, Oh WC, Kwon HB, Kubota Y, So PTC, Nedivi E. Inhibitory Synapses Are Repeatedly Assembled and Removed at Persistent Sites In Vivo. Neuron 2016; 89:756-69. [PMID: 26853302 DOI: 10.1016/j.neuron.2016.01.010] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 06/11/2015] [Accepted: 12/24/2015] [Indexed: 11/24/2022]
Abstract
Older concepts of a hard-wired adult brain have been overturned in recent years by in vivo imaging studies revealing synaptic remodeling, now thought to mediate rearrangements in microcircuit connectivity. Using three-color labeling and spectrally resolved two-photon microscopy, we monitor in parallel the daily structural dynamics (assembly or removal) of excitatory and inhibitory postsynaptic sites on the same neurons in mouse visual cortex in vivo. We find that dynamic inhibitory synapses often disappear and reappear again in the same location. The starkest contrast between excitatory and inhibitory synapse dynamics is on dually innervated spines, where inhibitory synapses frequently recur while excitatory synapses are stable. Monocular deprivation, a model of sensory input-dependent plasticity, shortens inhibitory synapse lifetimes and lengthens intervals to recurrence, resulting in a new dynamic state with reduced inhibitory synaptic presence. Reversible structural dynamics indicate a fundamentally new role for inhibitory synaptic remodeling--flexible, input-specific modulation of stable excitatory connections.
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Affiliation(s)
- Katherine L Villa
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Kalen P Berry
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jaichandar Subramanian
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jae Won Cha
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Won Chan Oh
- Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Hyung-Bae Kwon
- Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA; Max Planck Institute of Neurobiology, Martinsried 82152, Germany
| | - Yoshiyuki Kubota
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki 444-8585, Japan; Department of Physiological Science, Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8585, Japan; JST, CREST, Tokyo 102-0076, Japan
| | - Peter T C So
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Elly Nedivi
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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21
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Gross GG, Junge JA, Mora RJ, Kwon HB, Olson CA, Takahashi TT, Liman ER, Ellis-Davies GCR, McGee AW, Sabatini BL, Roberts RW, Arnold DB. Recombinant probes for visualizing endogenous synaptic proteins in living neurons. Neuron 2013; 78:971-85. [PMID: 23791193 DOI: 10.1016/j.neuron.2013.04.017] [Citation(s) in RCA: 194] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2013] [Indexed: 11/29/2022]
Abstract
The ability to visualize endogenous proteins in living neurons provides a powerful means to interrogate neuronal structure and function. Here we generate recombinant antibody-like proteins, termed Fibronectin intrabodies generated with mRNA display (FingRs), that bind endogenous neuronal proteins PSD-95 and Gephyrin with high affinity and that, when fused to GFP, allow excitatory and inhibitory synapses to be visualized in living neurons. Design of the FingR incorporates a transcriptional regulation system that ties FingR expression to the level of the target and reduces background fluorescence. In dissociated neurons and brain slices, FingRs generated against PSD-95 and Gephyrin did not affect the expression patterns of their endogenous target proteins or the number or strength of synapses. Together, our data indicate that PSD-95 and Gephyrin FingRs can report the localization and amount of endogenous synaptic proteins in living neurons and thus may be used to study changes in synaptic strength in vivo.
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Affiliation(s)
- Garrett G Gross
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
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22
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Olson JP, Kwon HB, Takasaki KT, Chiu CQ, Higley MJ, Sabatini BL, Ellis-Davies GCR. Optically selective two-photon uncaging of glutamate at 900 nm. J Am Chem Soc 2013; 135:5954-7. [PMID: 23577752 DOI: 10.1021/ja4019379] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have synthesized a 7-diethylaminocoumarin (DEAC) derivative that allows wavelength-selective two-photon uncaging at 900 nm versus 720 nm. This new caging chromophore, called DEAC450, has an extended π-electron moiety at the 3-position that shifts the absorption spectrum maximum of DEAC from 375 to 450 nm. Two-photon excitation at 900 nm was more than 60-fold greater than at 720 nm. Two-photon uncaging of DEAC450-Glu at 900 nm at spine heads on pyramidal neurons in acutely isolated brain slices generated postsynaptic responses that were similar to spontaneous postsynaptic excitatory miniature currents, whereas significantly higher energies at 720 nm evoked no currents. Since many nitroaromatic caged compounds are two-photon active at 720 nm, optically selective uncaging of DEAC450-caged biomolecules at 900 nm may allow facile two-color optical interrogation of bimodal signaling pathways in living tissue with high resolution for the first time.
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Affiliation(s)
- Jeremy P Olson
- Department of Neuroscience, Mount Sinai School of Medicine, New York, New York 10029, USA
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23
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Abstract
The purpose of this study was to compare the speech function of low height bulb obturators with that of high height bulb obturators. Thirteen maxillectomy patients, who underwent post-operative prosthodontic rehabilitations, were included. Two obturators of the same design except for different bulb heights were fabricated for each maxillectomy patient. One of the two obturators had high bulb design and the other had low bulb design. After one of the obturators was used for a period of 3 weeks, the patient's speaking functions were evaluated by measuring nasalance scores, formant frequencies, and vowel working space areas. The same procedures were repeated with the second obturator following another 3-week period of usage. In addition, the effect of delivery sequence and anatomic conditions related to maxillectomy were analysed. The results demonstrated that the nasalance scores with the low bulb obturators were significantly higher than those with the high bulb obturators. There were no significant differences in formant frequencies based on the bulb height of the obturators. The vowel working spaces for the two obturators were similar in shape and there were no significant differences between the vowel working space areas created by the two obturators. The delivery sequence affected the results. However, there were no significant differences related to the other anatomical variables. Although low bulb obturators might function similarly with high bulb obturators in terms of the articulation of speech, they would exhibit a difficulty in controlling hypernasality in maxillectomy patients.
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Affiliation(s)
- H B Kwon
- Department of Prosthodontics, School of Dentistry, Seoul, Korea
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24
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Abstract
Presynaptic autoreceptors modulate transmitter release at many synapses. At the mossy fiber to CA3 pyramidal cell (mf-CA3) synapse, two types of glutamatergic autoreceptors have been identified: transmitter release is reportedly suppressed by metabotropic glutamate receptors (mGluRs) and augmented by kainate receptors (KARs). However, the net effect of these autoreceptors when activated by endogenous glutamate is unknown. Here, we show that during low-frequency mossy fiber stimulation, glutamate acting through presynaptic mGluRs substantially suppresses transmitter release. However, using similar recording conditions, we find that presynaptic KARs are insufficient to facilitate transmitter release over a wide range of mossy fiber stimulus frequencies, indicating that the uniquely robust mf-CA3 short-term plasticity is KAR independent. Furthermore, we report that actions generally attributed to presynaptic KARs are likely due to activation of recurrent CA3 network activity. Thus, negative feedback via presynaptic mGluRs is the dominant mode of glutamatergic autoregulation at the mf-CA3 synapse.
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Affiliation(s)
| | - Pablo E. Castillo
- Dominick P. Purpura Department of Neuroscience Albert Einstein College of Medicine Bronx, New York 10461
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25
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Song JA, Oh DY, Moon JS, Geum D, Kwon HB, Seong JY. Involvement of the ser-glu-pro motif in ligand species-dependent desensitisation of the rat gonadotrophin-releasing hormone receptor. J Neuroendocrinol 2006; 18:757-66. [PMID: 16965294 DOI: 10.1111/j.1365-2826.2006.01469.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
There are two forms of gonadotrophin-releasing hormone (GnRH), GnRH-I and GnRH-II, in the vertebrate brain. Both GnRH-I and GnRH-II are thought to interact with the type-I GnRH receptor (GnRHR). The present study attempted to demonstrate whether GnRH-I and GnRH-II induce differential desensitisation of GnRHR and to identify the motif involved. Time course inositol phosphate (IP) accumulation assay reveals that, in cells expressing the wild-type rat GnRHR, GnRH-I induced continuous increase in IP production, whereas GnRH-II-induced IP production rate at later time points (30-120 min after ligand treatment) became attenuated. However, in cells expressing the mutant receptor in which the Ser-Glu-Pro (SEP) motif in extracellular loop 3 was replaced by Pro-Glu-Val (PEV), IP accumulation rates at later time points were more decreased by GnRH-I than GnRH-II. Ca2+ responses to repetitive GnRH applications reveal that GnRH-II desensitised the wild-type receptor faster than GnRH-I, whereas the opposite situation was observed in the PEV mutant. In addition, cell surface loss of GFP-tagged wild-type receptor was more facilitated by GnRH-II than GnRH-I, whereas that of the GFP-tagged PEV mutant receptor was more enhanced by GnRH-I than GnRH-II. The present study indicates that the SEP motif is potentially responsible for ligand species-dependent receptor desensitisation. Together, these results suggest that GnRH-I and GnRH-II may have different effects on mammalian type-I GnRHR via modulation of desensitisation rates.
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Affiliation(s)
- J A Song
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju, Korea
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26
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Li JH, Sicard F, Salam MA, Baek M, LePrince J, Vaudry H, Kim K, Kwon HB, Seong JY. Molecular cloning and functional characterization of a type-I neurotensin receptor (NTR) and a novel NTR from the bullfrog brain. J Mol Endocrinol 2005; 34:793-807. [PMID: 15956348 DOI: 10.1677/jme.1.01709] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Neurotensin (NT) is a tridecapeptide that functions as a neurotransmitter and neuromodulator in the nervous system. To date, three different types of NT receptor (NTR), NTR1, NTR2 and NTR3, have been identified only in mammalian species. In the present study we isolated the cDNAs for an NTR1 and a novel NTR in the bullfrog brain, designated bfNTR1 and bfNTR4 respectively. bfNTR1 and bfNTR4 encode 422- and 399-amino acid residue proteins respectively. bfNTR1 has a 64% amino acid identity with mammalian NTR1, and 34-37% identity with mammalian NTR2. bfNTR4 exhibits 43% and 45-47% identity with mammalian NTR1 and NTR2 respectively. Both receptors are mainly expressed in the brain and pituitary. bfNTR1 triggers both CRE-luc, a protein kinase A (PKA)-specific reporter, and c-fos-luc, a PKC-specific reporter, activities, indicating that bfNTR1 can activate PKA- and PKC-linked signaling pathways. However, bfNTR4 appears to be preferentially coupled to the PKA-linked pathway as it induces a higher CRE-luc activity than c-fos-luc activity. bfNTRs exhibit different pharmacological properties as compared with mammalian NTRs. Mammalian NTR1 but not NTR2 responds to NT, whereas both bfNTR1 and bfNTR4 show a high sensitivity to NT. SR 48692 and SR 142948A, antagonists for mammalian NTR1 but agonists for mammalian NTR2, function as antagonists for both bfNTR1 and bfNTR4. In conclusion, this report provides the first molecular, pharmacological and functional characterization of two NTRs in a non-mammalian vertebrate. These data should help to elucidate the phylogenetic history of the G protein-coupled NTRs in the vertebrate lineage as well as the structural features that determine their pharmacological properties.
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Affiliation(s)
- J H Li
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Republic of Korea
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27
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Makarevich AV, Sirotkin AV, Franek J, Kwon HB, Bulla J. The role of oxytocin, protein kinase A, and ERK-related MAP-kinase in the control of porcine ovarian follicle functions. Exp Clin Endocrinol Diabetes 2004; 112:108-14. [PMID: 15031777 DOI: 10.1055/s-2004-815766] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of our in vitro experiments was to study the role of oxytocin (OT), cAMP/protein kinase A (PKA), and mitogen-activated protein kinase (ERKs MAP-kinase) in the control of ovarian cell functions as well as the role of PKA and MAPK in mediating OT effects on these processes. The whole porcine ovarian follicles were cultured in the presence or absence of OT (1, 10, 100 ng/ml), PKA inhibitor Rp-cAMPS (10 nM), MAP-kinase inhibitor PD98059 (1 microg/ml), or their combination. The release of prostaglandins F (PGF) and E (PGE) were determined by RIA, PKA (alpha-cat subunit), the proliferation-associated peptide PCNA and ERK-1, -2 expression in cell lyzates were analysed by Western-blotting. OT stimulated the release of PGF and PGE, and accumulation of PKA, ERK-1/-2, and PCNA in cell lysate. PD98059 decreased the basal PGF and PGE output, as well as reduced both ERK-1 and ERK-2 accumulation in cell lysates. Rp-cAMPS decreased PKA accumulation in cell lysates. Rp-cAMPS prevented the OT-induced stimulation of PKA, ERK-1, ERK-2, PGF, and PGE, PD98059 did so for PKA, PGF, and PGE. However, PD98059 reduced either basal or OT-induced p-ERK level. OT-stimulated PCNA accumulation was only slightly modified by these blockers. These observations suggest that OT, PKA, and ERKs MAPK can be involved in the control of PGs release and proliferation of ovarian cells. The influence of OT on both PKA and MAPK, and the ability of PKA and MAPK blockers to prevent completely or partially OT effects suggest, that effects of OT on PGF and PGE can be mediated by both PKA and MAPK. The role of MAPK and PKA in mediating the proliferative effects of OT seems to be minor assuming the involvement of other intracellular messengers.
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Affiliation(s)
- A V Makarevich
- Research Institute of Animal Production, Nitra, Slovak Republic.
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Chandra S, Fornai F, Kwon HB, Yazdani U, Atasoy D, Liu X, Hammer RE, Battaglia G, German DC, Castillo PE, Südhof TC. Double-knockout mice for alpha- and beta-synucleins: effect on synaptic functions. Proc Natl Acad Sci U S A 2004; 101:14966-71. [PMID: 15465911 PMCID: PMC522043 DOI: 10.1073/pnas.0406283101] [Citation(s) in RCA: 326] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
An abundant presynaptic protein, alpha-synuclein, is centrally involved in the pathogenesis of Parkinson's disease. However, conflicting data exist about the normal function of alpha-synuclein, possibly because alpha-synuclein is redundant with the very similar beta-synuclein. To investigate the functions of synucleins systematically, we have now generated single- and double-knockout (KO) mice that lack alpha- and/or beta-synuclein. We find that deletion of synucleins in mice does not impair basic brain functions or survival. We detected no significant changes in the ultrastructure of synuclein-deficient synapses, in short- or long-term synaptic plasticity, or in the pool size or replenishment of recycling synaptic vesicles. However, protein quantitations revealed that KO of synucleins caused selective changes in two small synaptic signaling proteins, complexins and 14-3-3 proteins. Moreover, we found that dopamine levels in the brains of double-KO but not single-KO mice were decreased by approximately 20%. In contrast, serotonin levels were unchanged, and dopamine uptake and release from isolated nerve terminals were normal. These results show that synucleins are not essential components of the basic machinery for neurotransmitter release but may contribute to the long-term regulation and/or maintenance of presynaptic function.
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Affiliation(s)
- Sreeganga Chandra
- Center for Basic Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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29
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Acharjee S, Do-Rego JL, Oh DY, Moon JS, Ahn RS, Lee K, Bai DG, Vaudry H, Kwon HB, Seong JY. Molecular cloning, pharmacological characterization, and histochemical distribution of frog vasotocin and mesotocin receptors. J Mol Endocrinol 2004; 33:293-313. [PMID: 15291760 DOI: 10.1677/jme.0.0330293] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The neurohypophysial nonapeptides vasotocin (VT) and mesotocin (MT) are the amphibian counterparts of arginine vasopressin (AVP) and oxytocin (OT). We have here reported the cloning and functional characterization of the receptors for vasotocin (VTR) and mesotocin (MTR) in two species of frog, Rana catesbeiana and Rana esculenta. The frog VTR and MTR cDNAs encode proteins of 419 and 384 amino acids respectively. Frog VTR exhibits a high degree of sequence identity with the mammalian AVP-1a (V1a) receptor while the frog MTR possesses a high degree of sequence identity with the mammalian OT receptor. Activation of VTR induced both c-fos promoter- and cAMP-responsive element (CRE)-driven transcriptional activities, while activation of MTR induced c-fos promoter-driven transcriptional activity but failed to evoke CRE-driven transcriptional activity, suggesting differential G protein coupling between VTR and MTR. The VTR exhibited the highest sensitivity for VT followed by OT>AVP approximately MT, whereas the MTR showed preferential ligand sensitivity for MT>OT>VT>AVP. A V1a agonist but not V2 and OT agonists substantially activated both VTR and MTR with a similar sensitivity. V1a, V2 and OT antagonists inhibited MT-induced MTR activation but not VT-induced VTR activation. In the frog brain, VTR and MTR mRNAs were found to be widely expressed in the telencephalon, diencephalon and mesencephalon, and exhibited very similar regional distribution. In the pituitary, VTR and MTR were expressed in the distal and intermediate lobes but were virtually absent in the neural lobe. Taken together, these data indicated that, although the distribution of VTR and MTR largely overlaps in the frog brain and pituitary, VT and MT may play distinct activities owing to the ligand selectivity and different signaling pathways activated by their receptors.
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Affiliation(s)
- S Acharjee
- Hormone Research Center, School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Korea
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Abstract
Growth hormone (GH), prostaglandins F (PGF) and prostaglandins E (PGE) are important regulators of ovarian function. Therefore, interrelationships between GH and these substances and their intracellular mechanisms might be of physiological significance in the ovary. The aims of this study on cultured porcine ovarian granulosa cells were to determine the effect of GH on the secretion of oxytocin (OT), PGF and PGE and whether MAP kinase could be involved in the mediation of GH action. Experiments were carried out with cultured porcine granulosa cells to investigate the effects of exogenous pGH (1-100 ng/ml) on the expression of MAP kinase (ERK-1, -2) and of PGH (1-100 ng/ml) and the MAP kinase blocker PD 98059 (1 microg/ml) on the secretion of PGF, PGE and OT. The cellular content of ERK-1 and -2 was analyzed by Western immunoblotting and immunocytochemistry, whilst PGF, PGE and OT accumulation in the medium was measured by RIA. Addition of GH to culture medium significantly altered the pattern of ovarian ERK MAP kinase on SDS-PA gels: the 44 and 42 kDa bands were reduced and additional 50 and 48 kDa bands appeared. Moreover, there was an increase in the percentage of cells containing ERK MAP kinase. GH stimulated the secretion of PGF (at a concentration of 1 ng GH per ml medium) and OT (100 ng GH per ml), but not PGE. The MAP kinase blocker alone did not affect PGF, PGE and OT secretion but did prevent the stimulatory effects of GH on PGF and induced stimulatory action of GH (10 ng/ml) on PGE. GH-stimulated OT secretion was unaffected. These observations confirm the role of GH in regulating porcine ovarian PGF, PGE and OT secretion and the presence of ERK MAP kinase in porcine granulosa cells. Furthermore, our studies demonstrate that MAP kinase-dependent intracellular mechanisms are dependent on GH, and that these mechanisms are involved in the mediation of GH action on ovarian PGF and PGE but not OT secretion.
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Affiliation(s)
- Alexander V Sirotkin
- Endocrinology Laboratory, Research Institute of Animal Production, Hlohovská 2, 949 92 Nitra, Slovakia.
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Kwon HB, Kim SH, Kim SE, Jang IH, Ahn Y, Lee WJ, Choi KY. Drosophila extracellular signal-regulated kinase involves the insulin-mediated proliferation of Schneider cells. J Biol Chem 2002; 277:14853-8. [PMID: 11834735 DOI: 10.1074/jbc.m110366200] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Drosophila insulin pathway is involved in the control of the proliferation and size of the cell. The stimulation of Schneider cells with human insulin has been observed to activate Drosophila extracellular signal regulated kinase (DERK). However, the role of DERK in the regulation of proliferation is unknown. In this study, we have identified a role of DERK in the proliferation of Drosophila Schneider cells. The inhibition of DERK activity by the overexpression of DMKP-3, an ERK-specific mitogen-activated protein kinase (MAPK) phosphatase, inhibited G(1) to S phase cell cycle progression as well as bromodeoxyuridine (BrdU) incorporation, which were previously increased by human insulin. However, DMKP-3 overexpression did not significantly reduce cell size that was also enlarged by insulin treatment, which suggests the specificity of the ERK pathway in proliferation but not for cell size. G1 to S phase cell cycle progression and BrdU incorporation were also reduced by catalytically inactive DMKP-3 mutant, and they may be acquired by the trapping of DERK into cytosol. The depletion of DERK or DMKP-3 by inhibitory double-stranded RNA decreased and increased BrdU incorporation, respectively. Thus, we propose that DERK is involved in the proliferation of Schneider cells via the insulin pathway.
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Affiliation(s)
- Hyung-Bae Kwon
- Department of Biotechnology, Yonsei University College of Engineering, 134 Shinchon-dong, Seodaemun-gu, Korea
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Kim SH, Kwon HB, Kim YS, Ryu JH, Kim KS, Ahn Y, Lee WJ, Choi KY. Isolation and characterization of a Drosophila homologue of mitogen-activated protein kinase phosphatase-3 which has a high substrate specificity towards extracellular-signal-regulated kinase. Biochem J 2002; 361:143-51. [PMID: 11742539 PMCID: PMC1222289 DOI: 10.1042/bj3610143] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A partial C-terminal cDNA sequence of a novel Drosophila mitogen-activated protein kinase phosphatase (MKP), designated DMKP-3, was identified from an epitope expressed sequence tag database, and the missing N-terminal cDNA fragment was cloned from a Drosophila cDNA library. DMKP-3 is a protein of 411 amino acids, with a calculated molecular mass of 45.8 kDa; the deduced amino acid sequence is most similar to that of mammalian MKP-3. Recombinant DMKP-3 produced in Escherichia coli retained intrinsic tyrosine phosphatase activity. In addition, DMKP-3 specifically inhibited extracellular-signal-regulated kinase (ERK) activity, but was without a significant affect on c-Jun N-terminal kinase (JNK) and p38 activities, when it was overexpressed in Schneider cells. DMKP-3 interacted specifically with Drosophila ERK (DERK) via its N-terminal domain. In addition, DMKP-3 specifically inhibited Elk-1-dependent trans-reporter gene expression in mammalian CV1 cells, and dephosphorylated activated mammalian ERK in vitro. DMKP-3 is uniquely localized in the cytoplasm within Schneider cells, and gene expression is tightly regulated during development. Thus DMKP-3 is a Drosophila homologue of mammalian MKP-3, and may play important roles in the regulation of various developmental processes.
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Affiliation(s)
- Sun-Hong Kim
- Department of Biochemistry and Molecular Biology, Institute of Genetic Science, Yonsei University College of Medicine, Seoul 120-752, South Korea
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33
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Sirotkin AV, Makarevich AV, Kwon HB, Kotwica J, Bulla J, Hetényi L. Do GH, IGF-I and oxytocin interact by regulating the secretory activity of porcine ovarian cells? J Endocrinol 2001; 171:475-80. [PMID: 11739013 DOI: 10.1677/joe.0.1710475] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The aims of this study on porcine ovarian granulosa cells were to examine the effect of GH on oxytocin (OT), IGF-I and IGF-I receptors, IGF-binding protein-3 (IGFBP-3), progesterone and prostaglandin E (PGE), as well as to determine whether IGF-I and/or OT may be mediators of GH action. The cells were cultured either with porcine GH (pGH) (1 ng/ml to 10 microg/ml or 100 ng/ml only), antiserum against IGF-I (0.1%), antiserum against OT (0.1%) or a combination of GH (10 ng/ml) with antiserum against IGF-I or antiserum against OT (0.1%). The secretion of IGF-I, OT, IGFBP-3, progesterone and PGE was determined using RIA/IRMA, whilst the IGF-I binding sites were measured using a radioreceptor assay. It was observed that pGH increased the secretion of IGF-I and the abundance of IGF-I binding sites in granulosa cells. Furthermore, GH inhibited OT release, stimulated progesterone and PGE output, but had no significant effect on IGFBP-3 secretion. Immunoneutralization of IGF-I by antiserum against IGF-I inhibited PGE secretion, but it did not influence progesterone or IGFBP-3 secretion. Binding of OT by antiserum suppressed IGFBP-3, PGE, but not progesterone secretion. Neither immunoneutralization of IGF-I nor OT substantially prevented the effects of GH on progesterone, IGFBP and PGE. These observations demonstrate the involvement of GH, IGF-I and OT in the control of porcine ovarian secretory activity and the ability of GH to regulate IGF-I and OT production and IGF-I reception. Nevertheless, lack of correlation between the effects of GH, antiserum against IGF-I and antiserum against OT, as well as the inability of blockade of IGF-I or OT to prevent the effects of GH, suggests that IGF-I and OT, despite their dependence on GH, do not mediate GH action on ovarian cells.
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Affiliation(s)
- A V Sirotkin
- Research Institute of Animal Production, 949 92 Nitra, Slovakia.
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34
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Sirotkin AV, Makarevich AV, Corkins MR, Kotwica J, Kwon HB, Bulla J, Hetényi L. Secretory activity of bovine ovarian granulosa cells transfected with sense and antisense insulin-like growth factor (IGF) binding protein-3 and the response to IGF-I, GH, LH, oxytocin and oestradiol. J Mol Endocrinol 2001; 27:329-38. [PMID: 11719285 DOI: 10.1677/jme.0.0270329] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The aim of our in vitro experiments was to examine if IGF binding protein (IGFBP)-3 is involved in control of bovine ovarian secretory activity. For this purpose we performed the transfection of bovine granulosa cells with cDNA sense and antisense constructs increasing or inhibiting IGFBP-3 synthesis. The release of IGFBP-3, progesterone, oxytocin, IGF-I and prostaglandins F (PGF) and E (PGE) by control and transfected cells was compared. The transfected ovarian cells were cultured with and without bLH (100 ng/ml), bGH (100 ng/ml), IGF-I (10 ng/ml), oxytocin (10 ng/ml) and oestradiol-17beta (100 ng/ml). The concentration of IGFBP-3 produced was assessed using ligand and western blotting and secretion of progesterone, oxytocin, IGF-I, PGF and PGE was evaluated using RIA/IRMA techniques. Transfection of cells with the sense IGFBP-3 cDNA construct resulted in the expected increase in IGFBP-3 release, whereas the antisense IGFBP-3 construct induced the expected reduction in IGFBP-3 output. The granulosa cells transfected to overexpress IGFBP-3 had an increase in IGF-I, PGF and PGE release, and a decrease in basal and hormone- or growth factor-induced accumulation of progesterone and oxytocin. The granulosa cells transfected to have reduced IGFBP-3 expression gave primarily significant opposite findings. The present results suggest the involvement of IGFBP-3 in control of bovine ovarian steroid, peptide hormone, growth factor and prostaglandin release. IGFBP-3 is a physiological stimulator of IGF-I and prostaglandin release and an inhibitor of steroid and peptide hormone output.
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Affiliation(s)
- A V Sirotkin
- Laboratory of Endocrinology, Research Institute of Animal Production, Hlohovská 949 92 Nitra, Slovak Republic.
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35
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Wang L, Oh DY, Bogerd J, Choi HS, Ahn RS, Seong JY, Kwon HB. Inhibitory activity of alternative splice variants of the bullfrog GnRH receptor-3 on wild-type receptor signaling. Endocrinology 2001; 142:4015-25. [PMID: 11517181 DOI: 10.1210/endo.142.9.8383] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recently we characterized three distinct GnRH receptors in the bullfrog (bfGnRHR-1, bfGnRHR-2, and bfGnRHR-3). In the present study, we further investigated the expression and function of splice variants, generated from the primary bfGnRHR-3 transcript by exon skipping (splice variant 1), intron retention (splice variants 2 and 3), and/or transcriptional slippage (splice variant 4), apart from the constitutively spliced form (wild-type). Cellular expression and function of the splice variants were examined using a transient expression system. Immunoblot analysis revealed that the wild-type receptor and all splice variant proteins were expressed in transfected HeLa cells with no significant differences in expression levels. These splice variants showed a very low binding affinity to ligand and did not induce signal transduction in response to GnRH treatment. Interestingly, cotransfection of the wild-type with splice variants 2--4, but not with splice variant 1, significantly inhibited wild-type receptor-mediated signaling. Subcellular localization analysis of green fluorescent protein-tagged wild-type and splice variant proteins revealed that the wild-type receptor protein was mainly localized in the cell membrane, whereas the splice variant 1 protein was exclusively detected in the cytoplasm. The splice variant 2--4 proteins, however, were found in both the cell membrane and cytoplasm. The inhibition of wild-type receptor signaling by splice variants 2--4 and the subcellular localization of splice variants 2-4 suggest a possible physical interaction of splice variants 2--4 with the wild-type receptor protein. In addition, the ratio of mRNA levels of the wild-type to splice variants 2--4 significantly varied from hibernation (wild-type < splice variants 2--4) to the prebreeding season (wild-type > splice variants 2--4). Collectively, these results suggest that alternative splicing of the bfGnRHR-3 primary transcript plays a role in fine-tuning GnRH receptor function in amphibians.
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Affiliation(s)
- L Wang
- Hormone Research Center and Department of Biology, Chonnam National University, Kwangju, 500-757, Republic of Korea
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36
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Wang L, Yoo MS, Kang HM, Im WB, Choi HS, Bogerd J, Kwon HB. Cloning and characterization of cDNAs encoding the GnRH1 and GnRH2 precursors from bullfrog (Rana catesbeiana). J Exp Zool 2001; 289:190-201. [PMID: 11170016 DOI: 10.1002/1097-010x(20010215)289:3<190::aid-jez6>3.0.co;2-e] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have isolated the cDNAs encoding the GnRH1 and GnRH2 precursors, respectively, from bullfrog (Rana catesbeiana) brain. The first cDNA consists of 648 bp and contains an open-reading frame of 270 nucleotides, encoding the bullfrog GnRH1 precursor. The second cDNA consists of 1053 bp and contains an open-reading frame of 255 nucleotides, encoding the bullfrog GnRH2 precursor. Both types of bullfrog GnRH precursor have a similar molecular architecture as observed in other GnRH precursors, consisting of a signal peptide, followed by the GnRH decapeptide, a conserved carboxy-terminal amidation and proteolytical processing site, and a GnRH-associated peptide (GAP). In addition, we have identified a third cDNA, containing 24 additional nucleotides in its GAP-coding region. Genomic PCR and sequence analysis confirmed that this cDNA represents an alternative splice variant of the bullfrog GnRH2-precursor pre-mRNA. The bullfrog GnRH1 precursor exhibits 60% and less than 40% amino acid identity to its Xenopus and mammalian counterparts, respectively, whereas the bullfrog GnRH2 precursor displays 50% to 60% amino acid identity to that of its nonmammalian counterparts, but shares only 25% amino acid identity with its mammalian counterparts. Northern blot analysis revealed a single GnRH1-precursor mRNA species of approximately 0.75 kilobases, expressed in bullfrog forebrain, and a single GnRH2-precursor mRNA species of approximately 1.1 kilobases, expressed in bullfrog midbrain/hindbrain. Furthermore, both bullfrog GnRH-precursor mRNAs exhibited a differential spatiotemporal expression pattern. Genomic Southern blot analysis indicated that both bullfrog GnRH genes are present as single copy genes. This is the first report on the molecular cloning of a GnRH2-precursor cDNA from an amphibian species. In addition, we present data showing that alternative splicing is utilized to generate different GnRH2-precursor mRNAs. J. Exp. Zool. 289:190-201, 2001.
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Affiliation(s)
- L Wang
- Hormone Research Center and Department of Biology, Chonnam National University, Kwangju 500-757, Republic of Korea
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37
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Wang L, Bogerd J, Choi HS, Seong JY, Soh JM, Chun SY, Blomenröhr M, Troskie BE, Millar RP, Yu WH, McCann SM, Kwon HB. Three distinct types of GnRH receptor characterized in the bullfrog. Proc Natl Acad Sci U S A 2001; 98:361-6. [PMID: 11120886 PMCID: PMC14595 DOI: 10.1073/pnas.98.1.361] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
It has been proposed recently that two types of GnRH receptors (GnRHR) exist in a particular species. Here we present data demonstrating that at least three types of GnRHR are expressed in a single diploid species, the bullfrog. Three different cDNAs, encoding distinct types of bullfrog GnRHR (bfGnRHR-1, bfGnRHR-2, and bfGnRHR-3), were isolated from pituitary and hindbrain of the bullfrog. BfGnRHR-1 mRNA was expressed predominantly in pituitary, whereas bfGnRHR-2 and -3 mRNAs were expressed in brain. The bfGnRHR-1, bfGnRHR-2, and bfGnRHR-3 proteins have an amino acid identity of approximately 30% to approximately 35% with mammalian GnRHRs and approximately 40% to approximately 50% with nonmammalian GnRHRs. Interestingly, bfGnRHR-2 has an 85% amino acid homology with Xenopus GnRHR. Less than 53% amino acid identity was observed among the three bfGnRHRs. All isolated cDNAs encode functional receptors because their transient expression in COS-7 cells resulted in a ligand-dependent increase in inositol phosphate production. Notably, all three receptors exhibited a differential ligand selectivity. For all receptors, cGnRH-II has a higher potency than mGnRH. In addition, salmon GnRH also has a strikingly high potency to stimulate all three receptors. In conclusion, we demonstrated the presence of three GnRHRs in the bullfrog. Their expression in pituitary and brain suggests that bfGnRHRs play an important role in the regulation of reproductive functions in the bullfrog.
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MESH Headings
- Amino Acid Sequence
- Animals
- Blotting, Southern
- COS Cells
- Cloning, Molecular
- DNA Primers
- DNA, Complementary/genetics
- Gene Expression Regulation
- Humans
- Inositol Phosphates/metabolism
- Ligands
- Molecular Sequence Data
- Pituitary Gland/chemistry
- Protein Isoforms/chemistry
- Protein Isoforms/classification
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rana catesbeiana/genetics
- Receptors, LHRH/chemistry
- Receptors, LHRH/classification
- Receptors, LHRH/genetics
- Receptors, LHRH/metabolism
- Rhombencephalon/chemistry
- Sequence Alignment
- Sequence Homology, Amino Acid
- Substrate Specificity
- Transfection
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Affiliation(s)
- L Wang
- Hormone Research Center and Department of Biology, Chonnam National University, Kwangju 500-757, Republic of Korea
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Abstract
A 1.2-kb full-length cDNA sequence of a glyceraldehyde-3-phosphate dehydrogenase (GPD) gene was isolated from the mushroom, Pleurotus sajor-caju. The full-length cDNA of the GPD gene consists of 1248 nucleotides, predicted to encode a 36-kDa polypeptide consisting of 335 amino acid residues. Sequence analysis revealed that the GPD gene has more than 72-78% amino acid sequence homology with those of other Basidiomycetes. Expression of the GPD gene increased when P. sajor-caju was treated with various abiotic stresses, such as salt, cold, heat, and drought. There was an eightfold induction by drought treatment. Salt and cold stress induced four- and twofold induction of GPD gene expression, respectively. There was also a fivefold induction by heat stress. The GPD gene exhibits different expression patterns under different stress conditions. It reached its maximum expression level within two hours under cold or heat treatment. The mRNA levels of this gene increased proportionally to increasing treatment time under salt or dry conditions. Because the expression of GPD was significantly increased, we tested whether GPD could confer abiotic stress resistance when it was introduced into yeast cells. For this, a transgenic yeast harboring P. sajor-caju GPD was generated under the control of a constitutively expressed GAL promoter. The results from biofunctional analyses with GPD yeast transformants showed that GPD yeast transformants had significantly higher resistance to cold, salt, heat, and drought stresses.
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Affiliation(s)
- M J Jeong
- Division of Molecular Genetics, National Institute of Agricultural Science and Technology, Suwon, Korea.
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39
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Yeo ET, Kwon HB, Han SE, Lee JT, Ryu JC, Byu MO. Genetic engineering of drought resistant potato plants by introduction of the trehalose-6-phosphate synthase (TPS1) gene from Saccharomyces cerevisiae. Mol Cells 2000; 10:263-8. [PMID: 10901163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
In yeast, trehalose-6-phosphate synthase is a key enzyme for trehalose biosynthesis, encoded by the structural gene TPS1. Trehalose affects sugar metabolism as well as osmoprotection against several environmental stresses, such as heat and desiccation. The TPS1 gene of Saccharomyces cerevisiae was engineered under the control of the CaMV 35S promoter for constitutive expression in transgenic potato plants by Ti-plasmid of Agrobacterium-mediated transformation. The resulting TPS1 transgenic potato plants exhibited various morphological phenotypes in culture tubes, ranging from normal to severely retarded growth, including dwarfish growth, yellowish lancet-shaped leaves, and aberrant root development. However, the plants recovered from these negative growth effects when grown in a soil mixture. The TPS1 transgenic potato plants showed significantly increased drought resistance. These results suggest that the production of trehalose not only affects plant development but also improves drought tolerance.
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Affiliation(s)
- E T Yeo
- Molecular Genetics Division, National Institute of Agricultural Science and Technology, Suwon, Korea
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40
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Yoo MS, Kang HM, Choi HS, Kim JW, Troskie BE, Millar RP, Kwon HB. Molecular cloning, distribution and pharmacological characterization of a novel gonadotropin-releasing hormone ([Trp8] GnRH) in frog brain. Mol Cell Endocrinol 2000; 164:197-204. [PMID: 11026571 DOI: 10.1016/s0303-7207(00)00221-5] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
To date nine structural variants of GnRH have been identified in vertebrates and two additional forms have been isolated from a tunicate. In amphibians only mammalian GnRH ([Arg8] GnRH) and type II GnRH (chicken GnRH II, [His5, Trp7, Tyr8] GnRH) have been identified. In the present study, a full-length cDNA encoding a novel type of GnRH was isolated from pituitary of Rana dybowskii. The GnRH gene encodes a GnRH peptide ([Trp8] GnRH) in which tryptophan is substituted for arginine of mammalian GnRH Northern blot analysis revealed the presence of a single 500 bp transcript for the [Trp8] GnRH precursor in forebrain but its absence in testis, ovary, kidney and liver. Restriction digests of genomic DNA demonstrated a single copy of the gene. The [Trp8] GnRH immunoreactive cells were identified in the preoptic area of the frog brain. Synthetic [Trp8] GnRH was tested for its ability to stimulate inositol phosphate production by COS-1 cells transfected with the cloned Xenopus pituitary GnRH receptor and the cloned human GnRH receptor. [Trp8] GnRH had a potency of about 60% compared with mammalian GnRH ([Arg8] GnRH) for the Xenopus receptor, whereas the potency of [Trp8] GnRH was approximately 5% compared with mammalian GnRH for the human receptor. Both mammalian GnRH and [Trp8] GnRH were 1000-fold less potent than type II GnRH for the Xenopus GnRH receptor. The similar potency of [Arg8] GnRH and the novel [Trp8] GnRH for the Xenopus pituitary receptor indicates that, unlike the human receptor, the Xenopus receptor does not discriminate between these amino acids in position eight thereby allowing substitution of the arginine in the mammalian GnRH.
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Affiliation(s)
- M S Yoo
- Hormone Research Center, Chonnam National University, Kwangju, South Korea
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41
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Ha CM, Kang JH, Choi EJ, Kim MS, Park JW, Kim Y, Choi WS, Chun SY, Kwon HB, Lee BJ. Progesterone increases mRNA levels of pituitary adenylate cyclase-activating polypeptide (PACAP) and type I PACAP receptor (PAC(1)) in the rat hypothalamus. Brain Res Mol Brain Res 2000; 78:59-68. [PMID: 10891585 DOI: 10.1016/s0169-328x(00)00070-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) regulates pituitary hormone biosynthesis and secretion through its cognate receptors. PACAP also plays an important role in the regulation of ovarian steroid biosynthesis. If so, there might be a feedback regulation of hypothalamic PACAP synthesis by the pituitary and by ovarian steroids. In the present study, we used RNase protection assays to determine changes in mRNA levels of PACAP and type I PACAP receptor (PAC(1)) under the conditions of ovariectomy and replacement with ovarian steroids. Progesterone (P) alone or in combination with estradiol (E) induced significant increases in PACAP mRNA level in the medial basal hypothalamus (MBH) and PAC(1) mRNA levels in MBH and the preoptic area (POA). This finding suggests that feedback regulation takes place between the ovary and hypothalamic PACAP neurons. P is known to be a major regulatory feedback factor for hypothalamic luteinizing hormone-releasing hormone (LHRH) neurons, but P receptor is not present in these neurons. Therefore, we examined a possible involvement of PACAP in the feedback regulatory pathway of P to LHRH neurons. After an antisense PAC(1) oligodeoxynucleotide (ODN) was i.c.v.-injected into the third ventricle of E and P-treated rats, LHRH mRNA levels were determined. The ODN markedly decreased the P-induced increase in the LHRH mRNA level. Taken together, the present data suggest that PACAP may play a role as a mediator in the regulation of LHRH synthetic machinery by stimulatory feedback of P.
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MESH Headings
- Animals
- Antisense Elements (Genetics)
- Brain Chemistry/drug effects
- Brain Chemistry/genetics
- Feedback/physiology
- Female
- Gene Expression/drug effects
- Gene Expression/physiology
- Gonadotropin-Releasing Hormone/genetics
- Hypothalamus, Middle/cytology
- Hypothalamus, Middle/physiology
- Injections, Intraventricular
- Neurons/chemistry
- Neurons/physiology
- Neuropeptides/genetics
- Ovariectomy
- Pituitary Adenylate Cyclase-Activating Polypeptide
- Pituitary Gland, Anterior/cytology
- Pituitary Gland, Anterior/physiology
- Preoptic Area/cytology
- Preoptic Area/physiology
- Progesterone/pharmacology
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
- Receptors, Pituitary Hormone/genetics
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Affiliation(s)
- C M Ha
- Department of Biological Sciences, University of Ulsan, Ulsan 680-749, South Korea
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42
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Koh PO, Kwak SD, Kang SS, Cho GJ, Chun SY, Kwon HB, Choi WS. Expression of pituitary adenylate cyclase activating polypeptide (PACAP) and PACAP type I A receptor mRNAs in granulosa cells of preovulatory follicles of the rat ovary. Mol Reprod Dev 2000; 55:379-86. [PMID: 10694744 DOI: 10.1002/(sici)1098-2795(200004)55:4<379::aid-mrd4>3.0.co;2-n] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pituitary adenylate cyclase activating polypeptide (PACAP) was isolated from ovine hypothalamus and known to stimulate the production of cAMP in anterior pituitary cells. In the recent report, the expression of PACAP was detected in preovulatory follicles, and treatment with PACAP stimulated the production of progesterone and prostaglandin E(2) through the action of AC and PLC pathways in the ovary. PACAP binds to three type receptors. Type I A receptor is coupled to adenylate cyclase (AC) and phospholipase C (PLC) pathways, while type I B and type II receptors are only coupled to AC. Thus, the present study aimed to evaluate the temporal expression of PACAP and its type I A receptor mRNAs in the rat ovary after treatment with pregnant mare's serum gonadotropin and human chorionic gonadotropin (hCG). Northern blot analysis showed that PACAP transcripts were transiently expressed from 3-9 hr after hCG treatment, reaching a maximum at 6 hr. During these time points, PACAP mRNAs were specifically and strongly expressed in granulosa cells and cumulus cells of large preovulatory follicles and interstitial glandular cells. Type I A receptor mRNAs were also transiently expressed in granulosa cells of large preovulatory follicles from 3-9 hr after hCG treatment. PACAP and its type I A receptor mRNAs were expressed in the same preovulatory follicles. These results demonstrate that PACAP acts as an autoregulator or pararegulator through type I A receptor in granulosa cells and cumulus cells of large preovulatory follicles. Thus, we suggest that PACAP may have a critical role in granulosa cells of preovulatory follicles for the preparation of ovulation.
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Affiliation(s)
- P O Koh
- Department of Histology, College of Veterinary Medicine, Gyeongsang National University, Chinju, Kyungnam, Korea
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43
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Park JI, Kim WJ, Wang L, Park HJ, Lee J, Park JH, Kwon HB, Tsafriri A, Chun SY. Involvement of progesterone in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide gene expression in pre-ovulatory follicles of rat ovary. Mol Hum Reprod 2000; 6:238-45. [PMID: 10694271 DOI: 10.1093/molehr/6.3.238] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The present study was designed to determine whether progesterone might have a role in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide (Pacap) gene expression in rat ovary. Northern blot analysis revealed that treatment of pregnant mare's serum gonadotrophin (PMSG)-primed immature rats with the progestin antagonist RU486 or an inhibitor of 3beta-hydroxysteroid dehydrogenase epostane, 1 h before HCG, resulted in a dose-dependent inhibition of the HCG-induced Pacap gene expression. In-situ hybridization demonstrated that the number of pre-ovulatory follicles expressing Pacap mRNA in their granulosa cells was greatly reduced in ovaries treated with RU486. Moreover, the suppressive effect of RU486 or epostane on the LH-induced Pacap gene expression in cultured pre-ovulatory follicles was reversed by co-treatment with the synthetic progestin R5020. We further cloned the 5'-flanking region of the rat Pacap gene and identified the presence of a consensus progesterone receptor element. When luciferase fusion genes containing Pacap gene promoter were transiently transfected into granulosa cells of pre-ovulatory follicles, luciferase activity was markedly stimulated by LH. Treatment with RU486 or epostane resulted in partial suppression of LH-stimulated PACAP promoter activity. Taken together, these results indicate that progesterone, acting through progesterone receptors, plays a role in gonadotrophin induction of Pacap gene expression in granulosa cells of pre-ovulatory follicles, and thereby may be involved in the process of ovulation.
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Affiliation(s)
- J I Park
- Hormone Research Center, Chonnam National University, Kwangju 500-757, Republic of Korea
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44
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Bandyopadhyay J, Bandyopadhyay A, Choi HS, Kwon HB, Kang HM. Cloning and characterization of cDNA encoding cdc2 kinase, a component of maturation-promoting factor, in Rana dybowskii. Gen Comp Endocrinol 2000; 117:313-22. [PMID: 10642452 DOI: 10.1006/gcen.1999.7420] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In order to understand the mechanism of oocyte maturation in seasonal-breeding wild frogs, we have cloned and sequenced a cDNA encoding Cdc2 kinase, a component of the maturation-promoting factor (MPF) in Rana dybowskii. About 1.2-kb cDNA was isolated by reverse transcription coupled to polymerase chain reaction (RT-PCR) and cDNA library screening. The cloned Rana Cdc2 cDNA encodes a complete open-reading frame with 302 amino acid residues, which deduce a 34-kDa protein. Homology of more than 80% was found between the deduced amino acid sequence of Rana Cdc2 and that of five phylogenetically distant organisms, and 94% identity was found between Rana and Xenopus. More importantly, the Thr14, Tyr15, and Thr161 residues, the phosphorylation sites for the activation of the enzyme, are highly conserved. In vitro-translated Rana Cdc2 cross-reacted with Xenopus p34(cdc2) antibody as shown by Western blot. Northern blot analysis showed that a 1.7-kb transcript was highly expressed in the gonads compared to other tissues, indicating the important role of Cdc2 kinase in gonads as a component of MPF. The cloned Rana Cdc2 cDNA also exhibited histone H1 kinase activity when expressed in CV-1 cells. In the present study, therefore, we have characterized the Rana Cdc2 kinase in amphibian, which will be helpful in understanding the process of oocyte maturation related to the reproduction cycle of wild frogs.
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Affiliation(s)
- J Bandyopadhyay
- Hormone Research Center, Chonnam National University, Kwangju, 500-757, Republic of Korea
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45
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Park HJ, Lee J, Wang L, Park JH, Kwon HB, Arimura A, Chun SY. Stage-specific expression of pituitary adenylate cyclase-activating polypeptide type I receptor messenger ribonucleic acid during ovarian follicle development in the rat. Endocrinology 2000; 141:702-9. [PMID: 10650952 DOI: 10.1210/endo.141.2.7322] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Expression of pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with considerable homology to vasoactive intestinal peptide, has been shown to be stimulated by gonadotropins in the ovary. The present studies further evaluated the cell-type specific expression and gonadotropin regulation of PACAP type I receptor (PACAPR) messenger RNA in immature rat ovaries and in cultured preovulatory follicles. Northern blot analysis of ovaries obtained from prepubertal rats revealed the increased expression of PACAPR during prepubertal development. The major cell types expressing PACAPR messenger RNA were granulosa cells of large preantral follicles. Treatment of immature rats with PMSG caused a decrease in ovarian PACAPR expression. In contrast, treatment with human (h) CG at 2 days after PMSG treatment stimulated ovarian PACAPR messenger RNA within 3-6 h in granulosa cells of preovulatory follicles. Treatment of cultured preovulatory follicles in vitro with LH further confirmed the time- and dose-dependent stimulation of PACAPR by gonadotropins in granulosa cells of preovulatory follicles. Moreover, RNase protection assay revealed that the short variant of ovarian PACAPR was the predominant form stimulated during prepubertal development and by gonadotropins. These results demonstrate the expression of PACAPR messenger RNA in granulosa cells of growing follicles and of preovulatory follicles stimulated by gonadotropins, and suggest that PACAP may play a role in the growth of developing follicles and in ovulation as an autocrine/paracrine factor.
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Affiliation(s)
- H J Park
- Hormone Research Center, Chonnam National University, Kwangju, Republic of Korea
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46
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Kim MY, Lee HK, Park JS, Park SH, Kwon HB, Soh J. Identification of a zeta-crystallin (quinone reductase)-like 1 gene (CRYZL1) mapped to human chromosome 21q22.1. Genomics 1999; 57:156-9. [PMID: 10191096 DOI: 10.1006/geno.1998.5714] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To identify a new gene(s) located on the yeast artificial chromosome (YAC) clone D142H8 that was mapped to human chromosome 21q22.1, purified YAC DNA from the clone was utilized directly as a probe to screen a human brain cDNA library after the suppression of human repetitive DNA. One cDNA clone hybridizing specifically to the YAC D142H8 DNA was identified. The clone has an insert of 1341 bp and the longest open reading frame of 349 amino acids. A search of GenBank revealed that the clone has a high degree of homology to zeta-crystallin (quinone reductase) at the amino acid level, and its nucleotide sequence represents the expressed sequence from the 50-kb segment of the human chromosome 21q11.1. Thus a new gene was named CRYZL1 (zeta-crystalline-like 1). Genomic Southern blot with total human and yeast DNAs suggests that CRYZL1 might be a single-copy gene. The fluorescence in situ hybridization procedure was applied, and the results showed that the gene mapped to the human chromosome 21q22.1 subband. The CRYZL1 mRNA was expressed in heart, brain, skeletal muscle, kidney, pancreas, liver, and lungs but at different levels in different tissues.
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Affiliation(s)
- M Y Kim
- College of Natural Sciences, Chonnam National University, Kwangju, 500-757 South Korea
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47
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Abstract
The steroidogenic acute regulatory (StAR) protein plays essential roles in the delivery of cytosolic cholesterol into the mitochondrial inner membrane, which is an acute regulated and rate-limiting step for the steroid hormone synthesis. Since retinoic acids (RAs) are known to induce the synthesis of steroid hormones in mouse Leydig cells in vitro, mouse Leydig tumour cells, K28, were used to determine the effect of RAs on the level of StAR mRNA by Northern blot analysis. The level of StAR mRNA reached the maximum in a 4-8 h treatment with all-trans-RA (atRA) or 9-cis-RA (9cRA), and the effects were dose-dependent. The effect of 9cRA on the levels of StAR mRNA was blocked by actinomycin D, which indicates that 9cRA might exert a direct effect on the transcription of the gene. Promoter/reporter constructs containing a 5'-flanking region of the mouse or rat StAR gene were prepared, and luciferase activity was assayed following transient transfection into K28 or adrenal tumour cells, Y1. The result revealed that the luciferase activity was increased by 4-5-fold in response to the treatment of 9cRA, which indicated that 9cRA participates transcriptional activation of the StAR protein gene.
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Affiliation(s)
- H K Lee
- Hormone Research Centre and Department of Biology, College of Natural Sciences, Chonnam National University, Kwangju, South Korea
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48
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Abstract
Studies were carried out to define the hormone-induced signal transduction pathway during maturation of Rana dybowskii oocytes. Rapamycin, a specific inhibitor of S6 kinase, blocked progesterone-induced oocyte germinal vesicle breakdown (GVBD) in a dose-dependent manner indicating that S6 kinase is required for meiotic maturation of Rana oocytes. Addition of rapamycin within 3 h, but not 6 h, of progesterone treatment inhibited GVBD. In contrast, cycloheximide, a general protein synthesis inhibitor, blocked GVBD even when added 9 h after progesterone addition. A twofold increase in S6 kinase activity occurred within 1 h of progesterone stimulation and rapamycin inhibited this activity. Rapamycin also suppressed, in a dose-dependent manner, progesterone-induced protein synthesis during the first 12 h of culture but less effectively later. Histone H1 kinase activity (maturation-promoting factor, MPF) was observed in oocyte extracts at two different times (between 6 and 9 h and at 24 h) following progesterone stimulation. Rapamycin blocked H1 kinase activity between 6 and 9 h of culture but not that observed at 24 h. In contrast, cycloheximide suppressed progesterone-induced H1 kinase activity as well as protein synthesis throughout the course of incubation. Such results indicate that rapamycin and cycloheximide have common and unique effects on oocyte maturation and suggest that progesterone-induced S6 kinase activity is closely associated with induction of protein synthesis and activation of MPF during oocyte maturation. Results in Rana contrast with those obtained in Xenopus where rapamycin inhibited S6 kinase but failed to inhibit GVBD or protein synthesis. Differences in the response of Rana and Xenopus oocytes to rapamycin are discussed in relation to seasonal, biochemical, and species variations.
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Affiliation(s)
- A Bandyopadhyay
- Hormone Research Center and Department of Biology, Chonnam National University, Kwangju, 500757, Republic of Korea
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49
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Lee J, Park HJ, Choi HS, Kwon HB, Arimura A, Lee BJ, Choi WS, Chun SY. Gonadotropin stimulation of pituitary adenylate cyclase-activating polypeptide (PACAP) messenger ribonucleic acid in the rat ovary and the role of PACAP as a follicle survival factor. Endocrinology 1999; 140:818-26. [PMID: 9927311 DOI: 10.1210/endo.140.2.6485] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP), a novel neuropeptide with considerable homology to vasoactive intestinal peptide and GH-releasing hormone, exists in two biologically active forms, PACAP-38 and -27. The presence of PACAP in the ovary has been demonstrated, where it stimulates steroidogenesis and cAMP accumulation in cultured granulosa cells. In the present study, gonadotropin regulation of PACAP gene expression was examined in PMSG/human (h)CG-treated immature rat ovaries and cultured preovulatory follicles. Northern blot analysis of ovaries obtained from PMSG/hCG-treated immature animals revealed the transient induction of PACAP transcripts by hCG, reaching a maximum at 6 h. The major cell types expressing PACAP messenger RNA were granulosa cells of preovulatory follicles and some theca/interstitial cells. In preovulatory follicles cultured in serum-free medium, PACAP transcripts were transiently induced by LH and FSH, reaching a maximum 6-9 h after stimulation in granulosa cells but not in theca cells. Treatment with cycloheximide or alpha-amanitin abolished LH-induced PACAP transcripts, indicating that new protein synthesis and transcription are necessary. Treatment with MDL-12,330A, an inhibitor of adenylate cyclase, inhibited LH-induced PACAP messenger RNA, and forskolin mimicked the LH action, implying the role of adenylate cyclase activation. In contrast, treatment with chelerythrine, an inhibitor of protein kinase C, and 2-O-tetradecanol-phorbol-13-acetate had no effect. We further tested the role of PACAP in follicle apoptosis using apoptotic DNA fragmentation analysis. Treatment with PACAP-38 suppressed follicle apoptosis in a dose-dependent manner. Moreover, the LH suppression of follicle apoptosis was partially blocked by cotreatment with PACAP-38 antagonist, indicating mediation by endogenous PACAP-38. These results suggest that PACAP, transiently induced by the gonadotropin surge, could be a local regulator of a number of events and may act as a follicle survival factor during the periovulatory period.
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Affiliation(s)
- J Lee
- Department of Biology, Chonnam National University, Kwangju, Republic of Korea
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50
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Kang SS, Son GH, Seong JY, Choi D, Kwon HB, Lee CC, Kim K. Noradrenergic neurotoxin suppresses gonadotropin-releasing hormone (GnRH) and GnRH receptor gene expression in ovariectomized and steroid-treated rats. J Neuroendocrinol 1998; 10:911-8. [PMID: 9870748 DOI: 10.1046/j.1365-2826.1998.00278.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study was designed to investigate whether noradrenergic neurotransmission regulates the gene expression of gonadotropin-releasing hormone (GnRH) in the preoptic area and GnRH receptor in the pituitary. To this end, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4, 50 mg/kg), an intraperitoneal (i.p.) injection of selective noradrenergic neurotoxin, was administered 1 h before progesterone (1 mg) treatment in ovariectomized and estradiol-treated prepubertal rats. Treatment with DSP4 effectively blocked the progesterone-induced increase in hypothalamic noradrenaline content, but not dopamine content, indicating that DSP4 selectively inhibits noradrenergic neurotransmission. DSP4 significantly blocked progesterone-induced increase in serum luteinizing hormone (LH) concentrations as well as GnRH release from hypothalamic fragments incubated in vitro. DSP4 concomitantly down-regulated GnRH mRNA levels in the preoptic area, as determined by competitive reverse transcription-polymerase chain reaction. DSP4 also clearly down-regulated progesterone-induced GnRH receptor mRNA levels in the pituitary, whereas it failed to alter LHbeta mRNA levels. In summary, blockade of noradrenergic neurotransmission with DSP4 resulted in profound reductions of hypothalamic GnRH and pituitary GnRH receptor gene expression.
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Affiliation(s)
- S S Kang
- Department of Molecular Biology and Research Centre for Cell Differentiation, College of Natural Sciences, Seoul National University, Korea
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