1
|
Ikenaga T, Nakamura T, Tajiri T, Tsuji M, Kato DI, Ineno T, Kobayashi Y, Tsutsui N, Kiyohara S. Diversity and evolution of serotonergic cells in taste buds of elasmobranchs and ancestral actinopterygian fish. Cell Tissue Res 2023; 394:431-439. [PMID: 37851111 DOI: 10.1007/s00441-023-03837-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Accepted: 10/05/2023] [Indexed: 10/19/2023]
Abstract
A subset of gustatory cells are serotonin immunoreactive (ir) in the mammalian taste bud. In the taste bud of lamprey, elongated gustatory-like cells are also serotonin-ir. In contrast, flattened serotonin-ir cells are located only in the basal region of the taste buds in the teleosts and amphibians. These serotonin-ir cells are termed as basal cells. To evaluate the evolution and diversity of serotonergic cells in the taste bud of amniote animals, we explored the distribution and morphology of serotonin-ir cells in the taste buds of ancestral actinopterygian fish (spotted gar, sturgeon, Polypterus senegalus) and elasmobranch (stingray). In all examined animals, the taste buds contained serotonin-ir cells in their basal part. The number of serotonin-ir basal cells in each taste bud was different between these fish species. They were highest in the stingray and decreased in the order of the Polypterus, sturgeon, and gar. While serotonin immunoreactivity was observed only in the basal cells in the taste buds of the ancestral actinopterygian fish, some elongated cells were also serotonin-ir in addition to the basal cells in the stingray taste buds. mRNA of tryptophan hydroxylase 1 (tph1), a rate-limiting enzyme of the serotonin synthesis, is expressed in both the elongated and basal cells of stingray taste buds, indicating that these cells synthesize the serotonin by themselves. These results suggest that the serotonin-ir basal cells arose from the ancestor of the cartilaginous fish, and serotonin-ir cells in the elasmobranch taste bud exhibit an intermediate aspect between the lamprey and actinopterygian fish.
Collapse
Affiliation(s)
- Takanori Ikenaga
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan.
| | - Tastufumi Nakamura
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan
| | - Tatsushi Tajiri
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan
| | - Minaki Tsuji
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan
| | - Dai-Ichiro Kato
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan
| | - Toshinao Ineno
- Aquaculture Research Institute, Shingu Station, Kindai University, Wakayama, Japan
| | - Yasuhisa Kobayashi
- Department of Fisheries, Faculty of Agriculture, Kindai University, Nara, 631-0052, Japan
- Faculty of Science, Ushimado Marine Institute (UMI), Okayama University, Okayama, 701-4303, Japan
| | - Naoaki Tsutsui
- Department of Life Sciences, Graduate School of Bioresources, Mie University, Mie, 514-8507, Japan
- Faculty of Science, Ushimado Marine Institute (UMI), Okayama University, Okayama, 701-4303, Japan
| | - Sadao Kiyohara
- Graduate School of Science and Engineering, Kagoshima University, Kagoshima, 890-0065, Japan
| |
Collapse
|
2
|
Expressing acetylcholine receptors after innervation suppresses spontaneous vesicle release and causes muscle fatigue. Sci Rep 2017; 7:1674. [PMID: 28490756 PMCID: PMC5431962 DOI: 10.1038/s41598-017-01900-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 04/04/2017] [Indexed: 02/04/2023] Open
Abstract
The formation and function of synapses are tightly orchestrated by the precise timing of expression of specific molecules during development. In this study, we determined how manipulating the timing of expression of postsynaptic acetylcholine receptors (AChRs) impacts presynaptic release by establishing a genetically engineered zebrafish line in which we can freely control the timing of AChR expression in an AChR-less fish background. With the delayed induction of AChR expression after an extensive period of AChR-less development, paralyzed fish displayed a remarkable level of recovery, exhibiting a robust escape response following developmental delay. Despite their apparent behavioral rescue, synapse formation in these fish was significantly altered as a result of delayed AChR expression. Motor neuron innervation determined the sites for AChR clustering, a complete reversal of normal neuromuscular junction (NMJ) development where AChR clustering precedes innervation. Most importantly, among the three modes of presynaptic vesicle release, only the spontaneous release machinery was strongly suppressed in these fish, while evoked vesicle release remained relatively unaffected. Such a specific presynaptic change, which may constitute a part of the compensatory mechanism in response to the absence of postsynaptic AChRs, may underlie symptoms of neuromuscular diseases characterized by reduced AChRs, such as myasthenia gravis.
Collapse
|
3
|
Zebrafish mutants of the neuromuscular junction: swimming in the gene pool. J Physiol Sci 2015; 65:217-21. [PMID: 25782439 PMCID: PMC4408355 DOI: 10.1007/s12576-015-0372-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 02/28/2015] [Indexed: 01/07/2023]
Abstract
This review provides an overview of zebrafish mutants with dysfunctional acetylcholine receptors or related proteins at the neuromuscular junction (NMJ). The NMJ, which has served as the classical model of the chemical synapse, uses acetylcholine as the neurotransmitter, and mutations of proteins involved in the signaling cascade lead to a variety of behavioral phenotypes. Mutants isolated after random chemical mutagenesis screening are summarized, and advances in the field resulting from these mutants are discussed.
Collapse
|
4
|
A single mutation in the acetylcholine receptor δ-subunit causes distinct effects in two types of neuromuscular synapses. J Neurosci 2014; 34:10211-8. [PMID: 25080583 DOI: 10.1523/jneurosci.0426-14.2014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mutations in AChR subunits, expressed as pentamers in neuromuscular junctions (NMJs), cause various types of congenital myasthenic syndromes. In AChR pentamers, the adult ε subunit gradually replaces the embryonic γ subunit as the animal develops. Because of this switch in subunit composition, mutations in specific subunits result in synaptic phenotypes that change with developmental age. However, a mutation in any AChR subunit is considered to affect the NMJs of all muscle fibers equally. Here, we report a zebrafish mutant of the AChR δ subunit that exhibits two distinct NMJ phenotypes specific to two muscle fiber types: slow or fast. Homozygous fish harboring a point mutation in the δ subunit form functional AChRs in slow muscles, whereas receptors in fast muscles are nonfunctional. To test the hypothesis that different subunit compositions in slow and fast muscles underlie distinct phenotypes, we examined the presence of ε/γ subunits in NMJs using specific antibodies. Both wild-type and mutant larvae lacked ε/γ subunits in slow muscle synapses. These findings in zebrafish suggest that some mutations in human congenital myasthenic syndromes may affect slow and fast muscle fibers differently.
Collapse
|
5
|
Crawford BD, Po MD, Saranyan PV, Forsberg D, Schulz R, Pilgrim DB. Mmp25β facilitates elongation of sensory neurons during zebrafish development. Genesis 2014; 52:833-48. [PMID: 25074687 DOI: 10.1002/dvg.22803] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 07/23/2014] [Accepted: 07/25/2014] [Indexed: 02/04/2023]
Abstract
Matrix metalloproteinases (MMPs) are a large and complex family of zinc-dependent endoproteinases widely recognized for their roles in remodeling the extracellular matrix (ECM) during embryonic development, wound healing, and tissue homeostasis. Their misregulation is central to many pathologies, and they have therefore been the focus of biomedical research for decades. These proteases have also recently emerged as mediators of neural development and synaptic plasticity in vertebrates, however, understanding of the mechanistic basis of these roles and the molecular identities of the MMPs involved remains far from complete. We have identified a zebrafish orthologue of mmp25 (a.k.a. leukolysin; MT6-MMP), a membrane-type, furin-activated MMP associated with leukocytes and invasive carcinomas, but which we find is expressed by a subset of the sensory neurons during normal embryonic development. We detect high levels of Mmp25β expression in the trigeminal, craniofacial, and posterior lateral line ganglia in the hindbrain, and in Rohon-Beard cells in the dorsal neural tube during the first 48 h of embryonic development. Knockdown of Mmp25β expression with morpholino oligonucleotides results in larvae that are uncoordinated and insensitive to touch, and which exhibit defects in the development of sensory neural structures. Using in vivo zymography, we observe that Mmp25β morphant embryos show reduced Type IV collagen degradation in regions of the head traversed by elongating axons emanating from the trigeminal ganglion, suggesting that Mmp25β may play a pivotal role in mediating ECM remodeling in the vicinity of these elongating axons.
Collapse
Affiliation(s)
- Bryan D Crawford
- Department of Biology, University of New Brunswick, New Brunswick, Canada; Department of Biological Sciences, University of Alberta, Alberta, Canada; Department of Pharmacology, University of Alberta, Alberta, Canada
| | | | | | | | | | | |
Collapse
|
6
|
Abstract
BACKGROUND Zebrafish is an amenable vertebrate model useful for the study of development and genetics. Small molecule screenings in zebrafish have successfully identified several drugs that affect developmental process. OBJECTIVE This review covers the basics of zebrafish muscle system such as muscle development and muscle defects. It also reviews the potential use of zebrafish for chemical screening with regards to muscle disorders. CONCLUSION During embryogenesis, zebrafish start to coil their body by contracting trunk muscles 17 h postfertilization, indicating that a motor circuit and skeletal muscle are functionally developed at early stages. Mutagenesis screens in zebrafish have identified many motility mutants that display morphological or functional defects in the CNS, clustering defects of acetylcholine receptors at the neuromuscular junctions or pathological defects of muscles. Most of the muscular mutants are useful as animal models of human muscle disease such as muscle dystrophy. As zebrafish live in water, pharmacological drugs are easily assayable during development, and thus zebrafish may be used to determine novel drugs that mitigate muscle disease.
Collapse
Affiliation(s)
- Hiromi Hirata
- Nagoya University, Graduate School of Science, Proof to Hiromi Hirata Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan +81 52 789 2980 ; +81 52 789 2979 ;
| |
Collapse
|
7
|
Acetylcholine receptors enable the transport of rapsyn from the Golgi complex to the plasma membrane. J Neurosci 2012; 32:7356-63. [PMID: 22623681 DOI: 10.1523/jneurosci.0397-12.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The accumulation of acetylcholine receptors (AChRs) at nerve terminals is critical for signal transmission at the neuromuscular junction, and rapsyn is essential for this process. Previous studies suggest that AChRs might direct rapsyn self-clusters to the synapse. In vivo experiments with fluorescently tagged AChR or rapsyn in zebrafish larvae revealed that rapsyn self-clusters separate from AChRs did not exist before synapse formation. Examination of rapsyn in the AChR-less mutant sofa potato revealed that rapsyn in the absence of AChR was localized in the Golgi complex. Expression of muscle-type AChR in sofa potato restored synaptic clustering of rapsyn, while neuronal type AChR had no effect. To determine whether this requirement of protein interaction is reciprocal, we examined the mutant twitch once, which has a missense mutation in rapsyn. While the AChRs distributed nonsynaptically on the plasma membrane in twitch once, mutant rapsyn was retained in the Golgi complex. We conclude that AChRs enable the transport of rapsyn from the Golgi complex to the plasma membrane through a molecule-specific interaction.
Collapse
|
8
|
Papke RL, Ono F, Stokes C, Urban JM, Boyd RT. The nicotinic acetylcholine receptors of zebrafish and an evaluation of pharmacological tools used for their study. Biochem Pharmacol 2012; 84:352-65. [PMID: 22580045 DOI: 10.1016/j.bcp.2012.04.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/27/2012] [Accepted: 04/30/2012] [Indexed: 01/17/2023]
Abstract
Zebrafish (Danio rerio) have been used to study multiple effects of nicotine, for example on cognition, locomotion, and stress responses, relying on the assumption that pharmacological tools will operate similarly upon molecular substrates in the fish and mammalian systems. We have cloned the zebrafish nicotinic acetylcholine receptor (nAChR) subunits and expressed key nAChR subtypes in Xenopus oocytes including neuronal (α4β2, α2β2, α3β4, and α7) and muscle (α1β1(b)ɛδ) nAChR. Consistent with studies of mammalian nAChR, nicotine was relatively inactive on muscle-type receptors, having both low potency and efficacy. It had high efficacy but low potency for α7 receptors, and the best potency and good efficacy for α4β2 receptors. Cytisine, a key lead compound for the development of smoking cessation agents, is a full agonist for both mammalian α7 and α3β4 receptors, but a full agonist only for the fish α7, with surprisingly low efficacy for α3β4. The efficacy of cytisine for α4β2 was somewhat greater than typically reported for mammalian α4β2. The ganglionic blocker mecamylamine was most potent for blocking α3β4 receptors, least potent for α7, and roughly equipotent for the muscle receptors and the β2-containing nAChR. However, the block of β2-containing receptors was slowly reversible, consistent with effective targeting of these CNS-type receptors in vivo. Three prototypical α7-selective agonists, choline, tropane, and 4OH-GTS-21, were tested, and these agents were observed to activate both fish α7 and α4β2 nAChR. Our data therefore indicate that while some pharmacological tools used in zebrafish may function as expected, others will not.
Collapse
Affiliation(s)
- Roger L Papke
- Department of Pharmacology, University of Florida College of Medicine, Gainesville, FL, USA.
| | | | | | | | | |
Collapse
|
9
|
Ikenaga T, Urban JM, Gebhart N, Hatta K, Kawakami K, Ono F. Formation of the spinal network in zebrafish determined by domain-specific pax genes. J Comp Neurol 2011; 519:1562-79. [PMID: 21452218 PMCID: PMC3402917 DOI: 10.1002/cne.22585] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In the formation of the spinal network, various transcription factors interact to develop specific cell types. By using a gene trap technique, we established a stable line of zebrafish in which the red fluorescent protein (RFP) was inserted into the pax8 gene. RFP insertion marked putative pax8-lineage cells with fluorescence and inhibited pax8 expression in homozygous embryos. Pax8 homozygous embryos displayed defects in the otic vesicle, as previously reported in studies with morpholinos. The pax8 homozygous embryos survived to adulthood, in contrast to mammalian counterparts that die prematurely. RFP is expressed in the dorsal spinal cord. Examination of the axon morphology revealed that RFP(+) neurons include commissural bifurcating longitudinal (CoBL) interneurons, but other inhibitory neurons such as commissural local (CoLo) interneurons and circumferential ascending (CiA) interneurons do not express RFP. We examined the effect of inhibiting pax2a/pax8 expression on interneuron development. In pax8 homozygous fish, the RFP(+) cells underwent differentiation similar to that of pax8 heterozygous fish, and the swimming behavior remained intact. In contrast, the RFP(+) cells of pax2a/pax8 double mutants displayed altered cell fates. CoBLs were not observed. Instead, RFP(+) cells exhibited axons descending ipsilaterally, a morphology resembling that of V2a/V2b interneurons.
Collapse
Affiliation(s)
- Takanori Ikenaga
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jason M. Urban
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Nichole Gebhart
- The Whitney Laboratory for Marine Bioscience, University of Florida, St Augustine, FL, 32080, USA
| | - Kohei Hatta
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako-gun, Hyogo 678-1297, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics
- Department of Genetics, The Graduate University for Advanced Studies (SOKENDAI), 1111 Yata, Mishima, Shizuoka 411-8540, Japan
| | - Fumihito Ono
- Laboratory of Molecular Physiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, 20892, USA
| |
Collapse
|
10
|
Cows I, Bolland J, Nunn A, Kerins G, Stein J, Blackburn J, Hart A, Henry C, Britton JR, Coop G, Peeler E. Defining environmental risk assessment criteria for genetically modified fishes to be placed on the EU market. ACTA ACUST UNITED AC 2010. [DOI: 10.2903/sp.efsa.2010.en-69] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- I.G. Cows
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J.D. Bolland
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - A.D. Nunn
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - G. Kerins
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. Stein
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. Blackburn
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - A. Hart
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - C. Henry
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. R. Britton
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - G. Coop
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - E. Peeler
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| |
Collapse
|