1
|
Podobnik M, Singh AP, Fu Z, Dooley CM, Frohnhöfer HG, Firlej M, Stednitz SJ, Elhabashy H, Weyand S, Weir JR, Lu J, Nüsslein-Volhard C, Irion U. kcnj13 regulates pigment cell shapes in zebrafish and has diverged by cis-regulatory evolution between Danio species. Development 2023; 150:dev201627. [PMID: 37530080 PMCID: PMC10482006 DOI: 10.1242/dev.201627] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 07/21/2023] [Indexed: 08/03/2023]
Abstract
Teleost fish of the genus Danio are excellent models to study the genetic and cellular bases of pigment pattern variation in vertebrates. The two sister species Danio rerio and Danio aesculapii show divergent patterns of horizontal stripes and vertical bars that are partly caused by the divergence of the potassium channel gene kcnj13. Here, we show that kcnj13 is required only in melanophores for interactions with xanthophores and iridophores, which cause location-specific pigment cell shapes and thereby influence colour pattern and contrast in D. rerio. Cis-regulatory rather than protein coding changes underlie kcnj13 divergence between the two Danio species. Our results suggest that homotypic and heterotypic interactions between the pigment cells and their shapes diverged between species by quantitative changes in kcnj13 expression during pigment pattern diversification.
Collapse
Affiliation(s)
- Marco Podobnik
- Max Planck Institute for Biology, 72076 Tübingen, Germany
| | - Ajeet P. Singh
- Chemical Biology and Therapeutics, Novartis Institutes for BioMedical Research, Cambridge, MA 02139, USA
| | - Zhenqiang Fu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Christopher M. Dooley
- Department of Genetics, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | | | - Magdalena Firlej
- Friedrich Miescher Laboratory of the Max Planck Society, 72076 Tübingen, Germany
| | - Sarah J. Stednitz
- Department of Anatomy & Physiology, University of Melbourne, Victoria, 3010, Melbourne, Australia
| | - Hadeer Elhabashy
- Department of Protein Evolution, Max Planck Institute for Biology, 72076 Tübingen, Germany
- Institute for Bioinformatics and Medical Informatics, University of Tübingen, 72076 Tübingen, Germany
- Department of Computer Science, University of Tübingen, 72076 Tübingen, Germany
| | - Simone Weyand
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - John R. Weir
- Friedrich Miescher Laboratory of the Max Planck Society, 72076 Tübingen, Germany
| | - Jianguo Lu
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | | | - Uwe Irion
- Max Planck Institute for Biology, 72076 Tübingen, Germany
| |
Collapse
|
2
|
Dawes JHP, Kelsh RN. Cell Fate Decisions in the Neural Crest, from Pigment Cell to Neural Development. Int J Mol Sci 2021; 22:13531. [PMID: 34948326 PMCID: PMC8706606 DOI: 10.3390/ijms222413531] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 11/17/2022] Open
Abstract
The neural crest shows an astonishing multipotency, generating multiple neural derivatives, but also pigment cells, skeletogenic and other cell types. The question of how this process is controlled has been the subject of an ongoing debate for more than 35 years. Based upon new observations of zebrafish pigment cell development, we have recently proposed a novel, dynamic model that we believe goes some way to resolving the controversy. Here, we will firstly summarize the traditional models and the conflicts between them, before outlining our novel model. We will also examine our recent dynamic modelling studies, looking at how these reveal behaviors compatible with the biology proposed. We will then outline some of the implications of our model, looking at how it might modify our views of the processes of fate specification, differentiation, and commitment.
Collapse
Affiliation(s)
- Jonathan H. P. Dawes
- Centre for Networks and Collective Behaviour, University of Bath, Bath BA2 7AY, UK;
- Department of Mathematical Sciences, University of Bath, Bath BA2 7AY, UK
| | - Robert N. Kelsh
- Centre for Mathematical Biology, University of Bath, Bath BA2 7AY, UK
- Department of Biology & Biochemistry, University of Bath, Bath BA2 7AY, UK
| |
Collapse
|
3
|
Huang D, Lewis VM, Foster TN, Toomey MB, Corbo JC, Parichy DM. Development and genetics of red coloration in the zebrafish relative Danio albolineatus. eLife 2021; 10:70253. [PMID: 34435950 PMCID: PMC8416024 DOI: 10.7554/elife.70253] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 08/25/2021] [Indexed: 12/11/2022] Open
Abstract
Animal pigment patterns play important roles in behavior and, in many species, red coloration serves as an honest signal of individual quality in mate choice. Among Danio fishes, some species develop erythrophores, pigment cells that contain red ketocarotenoids, whereas other species, like zebrafish (D. rerio) only have yellow xanthophores. Here, we use pearl danio (D. albolineatus) to assess the developmental origin of erythrophores and their mechanisms of differentiation. We show that erythrophores in the fin of D. albolineatus share a common progenitor with xanthophores and maintain plasticity in cell fate even after differentiation. We further identify the predominant ketocarotenoids that confer red coloration to erythrophores and use reverse genetics to pinpoint genes required for the differentiation and maintenance of these cells. Our analyses are a first step toward defining the mechanisms underlying the development of erythrophore-mediated red coloration in Danio and reveal striking parallels with the mechanism of red coloration in birds.
Collapse
Affiliation(s)
- Delai Huang
- Department of Biology, University of Virginia, Charlottesville, United States
| | - Victor M Lewis
- Department of Biology, University of Virginia, Charlottesville, United States
| | - Tarah N Foster
- Department of Biological Science, University of Tulsa, Tulsa, United States
| | - Matthew B Toomey
- Department of Biological Science, University of Tulsa, Tulsa, United States.,Department of Pathology and Immunology, Washington University School of Medicine, St Louis, United States
| | - Joseph C Corbo
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, United States
| | - David M Parichy
- Department of Biology, University of Virginia, Charlottesville, United States.,Department of Cell Biology, University of Virginia, Charlottesville, United States
| |
Collapse
|
4
|
Abstract
Pterins are one of the major sources of bright coloration in animals. They are produced endogenously, participate in vital physiological processes and serve a variety of signalling functions. Despite their ubiquity in nature, pterin-based pigmentation has received little attention when compared to other major pigment classes. Here, we summarize major aspects relating to pterin pigmentation in animals, from its long history of research to recent genomic studies on the molecular mechanisms underlying its evolution. We argue that pterins have intermediate characteristics (endogenously produced, typically bright) between two well-studied pigment types, melanins (endogenously produced, typically cryptic) and carotenoids (dietary uptake, typically bright), providing unique opportunities to address general questions about the biology of coloration, from the mechanisms that determine how different types of pigmentation evolve to discussions on honest signalling hypotheses. Crucial gaps persist in our knowledge on the molecular basis underlying the production and deposition of pterins. We thus highlight the need for functional studies on systems amenable for laboratory manipulation, but also on systems that exhibit natural variation in pterin pigmentation. The wealth of potential model species, coupled with recent technological and analytical advances, make this a promising time to advance research on pterin-based pigmentation in animals.
Collapse
Affiliation(s)
- Pedro Andrade
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
| | - Miguel Carneiro
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
| |
Collapse
|
5
|
Gray RS, Gonzalez R, Ackerman SD, Minowa R, Griest JF, Bayrak MN, Troutwine B, Canter S, Monk KR, Sepich DS, Solnica-Krezel L. Postembryonic screen for mutations affecting spine development in zebrafish. Dev Biol 2021; 471:18-33. [PMID: 33290818 PMCID: PMC10785604 DOI: 10.1016/j.ydbio.2020.11.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [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: 08/17/2020] [Revised: 11/21/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023]
Abstract
The spine gives structural support for the adult body, protects the spinal cord, and provides muscle attachment for moving through the environment. The development and maturation of the spine and its physiology involve the integration of multiple musculoskeletal tissues including bone, cartilage, and fibrocartilaginous joints, as well as innervation and control by the nervous system. One of the most common disorders of the spine in human is adolescent idiopathic scoliosis (AIS), which is characterized by the onset of an abnormal lateral curvature of the spine of <10° around adolescence, in otherwise healthy children. The genetic basis of AIS is largely unknown. Systematic genome-wide mutagenesis screens for embryonic phenotypes in zebrafish have been instrumental in the understanding of early patterning of embryonic tissues necessary to build and pattern the embryonic spine. However, the mechanisms required for postembryonic maturation and homeostasis of the spine remain poorly understood. Here we report the results from a small-scale forward genetic screen for adult-viable recessive and dominant zebrafish mutations, leading to overt morphological abnormalities of the adult spine. Germline mutations induced with N-ethyl N-nitrosourea (ENU) were transmitted and screened for dominant phenotypes in 1229 F1 animals, and subsequently bred to homozygosity in F3 families; from these, 314 haploid genomes were screened for adult-viable recessive phenotypes affecting general body shape. We cumulatively found 40 adult-viable (3 dominant and 37 recessive) mutations each leading to a defect in the morphogenesis of the spine. The largest phenotypic group displayed larval onset axial curvatures, leading to whole-body scoliosis without vertebral dysplasia in adult fish. Pairwise complementation testing of 16 mutant lines within this phenotypic group revealed at least 9 independent mutant loci. Using massively-parallel whole genome or whole exome sequencing and meiotic mapping we defined the molecular identity of several loci for larval onset whole-body scoliosis in zebrafish. We identified a new mutation in the skolios/kinesin family member 6 (kif6) gene, causing neurodevelopmental and ependymal cilia defects in mouse and zebrafish. We also report multiple recessive alleles of the scospondin and a disintegrin and metalloproteinase with thrombospondin motifs 9 (adamts9) genes, which all display defects in spine morphogenesis. Our results provide evidence of monogenic traits that are essential for normal spine development in zebrafish, that may help to establish new candidate risk loci for spine disorders in humans.
Collapse
Affiliation(s)
- Ryan S Gray
- Department of Nutritional Sciences, Dell Pediatric Research Institute, University of Texas at Austin, Austin, TX, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
| | - Roberto Gonzalez
- Department of Nutritional Sciences, Dell Pediatric Research Institute, University of Texas at Austin, Austin, TX, USA
| | - Sarah D Ackerman
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ryoko Minowa
- Department of Nutritional Sciences, Dell Pediatric Research Institute, University of Texas at Austin, Austin, TX, USA
| | - Johanna F Griest
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Melisa N Bayrak
- Department of Nutritional Sciences, Dell Pediatric Research Institute, University of Texas at Austin, Austin, TX, USA
| | - Benjamin Troutwine
- Department of Nutritional Sciences, Dell Pediatric Research Institute, University of Texas at Austin, Austin, TX, USA
| | - Stephen Canter
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kelly R Monk
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA; Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR, 97239, USA.
| | - Diane S Sepich
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
| |
Collapse
|
6
|
Podobnik M, Frohnhöfer HG, Dooley CM, Eskova A, Nüsslein-Volhard C, Irion U. Evolution of the potassium channel gene Kcnj13 underlies colour pattern diversification in Danio fish. Nat Commun 2020; 11:6230. [PMID: 33277491 PMCID: PMC7718271 DOI: 10.1038/s41467-020-20021-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 06/10/2020] [Accepted: 11/06/2020] [Indexed: 12/20/2022] Open
Abstract
The genetic basis of morphological variation provides a major topic in evolutionary developmental biology. Fish of the genus Danio display colour patterns ranging from horizontal stripes, to vertical bars or spots. Stripe formation in zebrafish, Danio rerio, is a self-organizing process based on cell-contact mediated interactions between three types of chromatophores with a leading role of iridophores. Here we investigate genes known to regulate chromatophore interactions in zebrafish that might have evolved to produce a pattern of vertical bars in its sibling species, Danio aesculapii. Mutant D. aesculapii indicate a lower complexity in chromatophore interactions and a minor role of iridophores in patterning. Reciprocal hemizygosity tests identify the potassium channel gene obelix/Kcnj13 as evolved between the two species. Complementation tests suggest evolutionary change through divergence in Kcnj13 function in two additional Danio species. Thus, our results point towards repeated and independent evolution of this gene during colour pattern diversification.
Collapse
Affiliation(s)
- Marco Podobnik
- Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076, Tübingen, Germany
| | - Hans Georg Frohnhöfer
- Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076, Tübingen, Germany
| | - Christopher M Dooley
- Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076, Tübingen, Germany
- Max Planck Institute for Heart and Lung Research, Ludwigstrasse 43, 61231, Bad Nauheim, Germany
| | - Anastasia Eskova
- Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076, Tübingen, Germany
- IBM Research and Development, Schönaicher Straße 220, 71032, Böblingen, Germany
| | | | - Uwe Irion
- Max Planck Institute for Developmental Biology, Max-Planck-Ring 5, 72076, Tübingen, Germany.
| |
Collapse
|
7
|
|
8
|
Caetano-Lopes J, Henke K, Urso K, Duryea J, Charles JF, Warman ML, Harris MP. Unique and non-redundant function of csf1r paralogues in regulation and evolution of post-embryonic development of the zebrafish. Development 2020; 147:dev.181834. [PMID: 31932352 DOI: 10.1242/dev.181834] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [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: 06/21/2019] [Accepted: 12/19/2019] [Indexed: 01/26/2023]
Abstract
Evolution is replete with reuse of genes in different contexts, leading to multifunctional roles of signaling factors during development. Here, we explore osteoclast regulation during skeletal development through analysis of colony-stimulating factor 1 receptor (csf1r) function in the zebrafish. A primary role of Csf1r signaling is to regulate the proliferation, differentiation and function of myelomonocytic cells, including osteoclasts. We demonstrate the retention of two functional paralogues of csf1r in zebrafish. Mutant analysis indicates that the paralogues have shared, non-redundant roles in regulating osteoclast activity during the formation of the adult skeleton. csf1ra, however, has adopted unique roles in pigment cell patterning not seen in the second paralogue. We identify a unique noncoding element within csf1ra of fishes that is sufficient for controlling gene expression in pigment cells during development. As a role for Csf1r signaling in pigmentation is not observed in mammals or birds, it is likely that the overlapping roles of the two paralogues released functional constraints on csf1ra, allowing the signaling capacity of Csf1r to serve a novel function in the evolution of pigment pattern in fishes.
Collapse
Affiliation(s)
- Joana Caetano-Lopes
- Orthopaedic Research Laboratories, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Katrin Henke
- Orthopaedic Research Laboratories, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Katia Urso
- Departments of Orthopaedics and Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Jeffrey Duryea
- Department of Radiology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Julia F Charles
- Departments of Orthopaedics and Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Matthew L Warman
- Orthopaedic Research Laboratories, Boston Children's Hospital, Boston, MA 02115, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Matthew P Harris
- Orthopaedic Research Laboratories, Boston Children's Hospital, Boston, MA 02115, USA .,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
9
|
Eskova A, Frohnhöfer HG, Nüsslein-Volhard C, Irion U. Galanin Signaling in the Brain Regulates Color Pattern Formation in Zebrafish. Curr Biol 2020; 30:298-303.e3. [PMID: 31902721 PMCID: PMC6971688 DOI: 10.1016/j.cub.2019.11.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 10/02/2019] [Accepted: 11/11/2019] [Indexed: 12/29/2022]
Abstract
Color patterns are prominent features of many animals and are of high evolutionary relevance. In basal vertebrates, color patterns are composed of specialized pigment cells that arrange in multilayered mosaics in the skin. Zebrafish (Danio rerio), the preeminent model system for vertebrate color pattern formation, allows genetic screens as powerful approaches to identify novel functions in a complex biological system. Adult zebrafish display a series of blue and golden horizontal stripes, composed of black melanophores, silvery or blue iridophores, and yellow xanthophores. This stereotyped pattern is generated by self-organization involving direct cell contacts between all three types of pigment cells mediated by integral membrane proteins [1, 2, 3, 4, 5]. Here, we show that neuropeptide signaling impairs the striped pattern in a global manner. Mutations in the genes coding either for galanin receptor 1A (npm/galr1A) or for its ligand galanin (galn) result in fewer stripes, a pale appearance, and the mixing of cell types, thus resembling mutants with thyroid hypertrophy [6]. Zebrafish chimeras obtained by transplantations of npm/galr1A mutant blastula cells indicate that mutant pigment cells of all three types can contribute to a normal striped pattern in the appropriate host. However, loss of galr1A expression in a specific region of the brain is sufficient to cause the mutant phenotype in an otherwise wild-type fish. Increased thyroid hormone levels in mutant fish suggest that galanin signaling through Galr1A in the pituitary is an upstream regulator of the thyroid hormone pathway, which in turn promotes precise interactions of pigment cells during color pattern formation. Zebrafish stripes are generated by three types of self-organizing pigment cells Galanin signaling through Galr1A impairs zebrafish stripe formation globally Galr1A function in a specific brain region is required for pigment cell interactions Galanin signaling functions to downregulate thyroid hormone levels
Collapse
Affiliation(s)
- Anastasia Eskova
- Max-Planck-Institute for Developmental Biology, Department ECNV, Max-Planck-Ring 5, 72076 Tübingen, Germany
| | - Hans Georg Frohnhöfer
- Max-Planck-Institute for Developmental Biology, Department ECNV, Max-Planck-Ring 5, 72076 Tübingen, Germany
| | | | - Uwe Irion
- Max-Planck-Institute for Developmental Biology, Department ECNV, Max-Planck-Ring 5, 72076 Tübingen, Germany.
| |
Collapse
|
10
|
Saunders LM, Mishra AK, Aman AJ, Lewis VM, Toomey MB, Packer JS, Qiu X, McFaline-Figueroa JL, Corbo JC, Trapnell C, Parichy DM. Thyroid hormone regulates distinct paths to maturation in pigment cell lineages. eLife 2019; 8:e45181. [PMID: 31140974 PMCID: PMC6588384 DOI: 10.7554/elife.45181] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [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: 01/18/2019] [Accepted: 05/24/2019] [Indexed: 12/11/2022] Open
Abstract
Thyroid hormone (TH) regulates diverse developmental events and can drive disparate cellular outcomes. In zebrafish, TH has opposite effects on neural crest derived pigment cells of the adult stripe pattern, limiting melanophore population expansion, yet increasing yellow/orange xanthophore numbers. To learn how TH elicits seemingly opposite responses in cells having a common embryological origin, we analyzed individual transcriptomes from thousands of neural crest-derived cells, reconstructed developmental trajectories, identified pigment cell-lineage specific responses to TH, and assessed roles for TH receptors. We show that TH promotes maturation of both cell types but in distinct ways. In melanophores, TH drives terminal differentiation, limiting final cell numbers. In xanthophores, TH promotes accumulation of orange carotenoids, making the cells visible. TH receptors act primarily to repress these programs when TH is limiting. Our findings show how a single endocrine factor integrates very different cellular activities during the generation of adult form.
Collapse
Affiliation(s)
- Lauren M Saunders
- Department of Genome SciencesUniversity of WashingtonSeattleUnited States
- Department of BiologyUniversity of VirginiaCharlottesvilleUnited States
- Department of Cell BiologyUniversity of VirginiaCharlottesvilleUnited States
| | - Abhishek K Mishra
- Department of BiologyUniversity of VirginiaCharlottesvilleUnited States
- Department of Cell BiologyUniversity of VirginiaCharlottesvilleUnited States
| | - Andrew J Aman
- Department of BiologyUniversity of VirginiaCharlottesvilleUnited States
- Department of Cell BiologyUniversity of VirginiaCharlottesvilleUnited States
| | - Victor M Lewis
- Department of Genome SciencesUniversity of WashingtonSeattleUnited States
- Department of BiologyUniversity of VirginiaCharlottesvilleUnited States
- Department of Cell BiologyUniversity of VirginiaCharlottesvilleUnited States
| | - Matthew B Toomey
- Department of Pathology and ImmunologyWashington University School of MedicineSt. LouisUnited States
| | - Jonathan S Packer
- Department of Genome SciencesUniversity of WashingtonSeattleUnited States
| | - Xiaojie Qiu
- Department of Genome SciencesUniversity of WashingtonSeattleUnited States
| | | | - Joseph C Corbo
- Department of Pathology and ImmunologyWashington University School of MedicineSt. LouisUnited States
| | - Cole Trapnell
- Department of Genome SciencesUniversity of WashingtonSeattleUnited States
| | - David M Parichy
- Department of BiologyUniversity of VirginiaCharlottesvilleUnited States
- Department of Cell BiologyUniversity of VirginiaCharlottesvilleUnited States
| |
Collapse
|
11
|
Lister JA. Larval but not adult xanthophore pigmentation in zebrafish requires GTP cyclohydrolase 2 (gch2) function. Pigment Cell Melanoma Res 2019; 32:724-727. [PMID: 30896066 DOI: 10.1111/pcmr.12783] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [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: 12/28/2018] [Revised: 02/18/2019] [Accepted: 03/13/2019] [Indexed: 11/28/2022]
Abstract
Although xanthophores are found widely among poikilothermic species, the developmental and biochemical pathways underlying differentiation of these pteridine- and carotenoid-containing cells remain murky. I have identified a recessive zebrafish mutant, camembert (cmm), which displays defective xanthophore pigmentation during embryonic and larval stages with cells appearing grayish rather than yellow, but as an adult appears to have normally pigmented xanthophores and wild-type stripe pattern. Examination of molecular markers reveals that xanthophores are present in typical numbers and position in cmm embryos; however, the localization of transcripts for the gene GTP cyclohydrolase 2 (gch2), encoding a critical protein in the pteridine biosynthetic pathway, is strikingly altered. RT-PCR analysis indicates that gch2 transcripts in mutant embryos skip an exon or retain the intron upstream and that no correctly spliced mRNA is made. Sequencing of genomic DNA reveals that the skipped exon is intact, but the retained intron contains a deletion of approximately 180 base pairs, just upstream of the splice acceptor. Microinjection of a gch2 BAC clone rescues yellow pigmentation in camembert larvae, confirming that the pigmentation defect is due to mutation of gch2.
Collapse
Affiliation(s)
- James A Lister
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| |
Collapse
|
12
|
Breuer M, Guglielmi L, Zielonka M, Hemberger V, Kölker S, Okun JG, Hoffmann GF, Carl M, Sauer SW, Opladen T. QDPR homologues in Danio rerio regulate melanin synthesis, early gliogenesis, and glutamine homeostasis. PLoS One 2019; 14:e0215162. [PMID: 30995231 PMCID: PMC6469847 DOI: 10.1371/journal.pone.0215162] [Citation(s) in RCA: 9] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 03/27/2019] [Indexed: 12/18/2022] Open
Abstract
Dihydropteridine reductase (QDPR) catalyzes the recycling of tetrahydrobiopterin (BH4), a cofactor in dopamine, serotonin, and phenylalanine metabolism. QDPR-deficient patients develop neurological symptoms including hypokinesia, truncal hypotonia, intellectual disability and seizures. The underlying pathomechanisms are poorly understood. We established a zebrafish model for QDPR deficiency and analyzed the expression as well as function of all zebrafish QDPR homologues during embryonic development. The homologues qdpra is essential for pigmentation and phenylalanine metabolism. Qdprb1 is expressed in the proliferative zones of the optic tectum and eye. Knockdown of qdprb1 leads to up-regulation of pro-proliferative genes and increased number of phospho-histone3 positive mitotic cells. Expression of neuronal and astroglial marker genes is concomitantly decreased. Qdprb1 hypomorphic embryos develop microcephaly and reduced eye size indicating a role for qdprb1 in the transition from cell proliferation to differentiation. Glutamine accumulation biochemically accompanies the developmental changes. Our findings provide novel insights into the neuropathogenesis of QDPR deficiency.
Collapse
Affiliation(s)
- Maximilian Breuer
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Luca Guglielmi
- Heidelberg University, Medical Faculty Mannheim, Department of Cell and Molecular Biology, Mannheim, Germany
| | - Matthias Zielonka
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Verena Hemberger
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Stefan Kölker
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Jürgen G. Okun
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Georg F. Hoffmann
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Matthias Carl
- Heidelberg University, Medical Faculty Mannheim, Department of Cell and Molecular Biology, Mannheim, Germany
- University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), Laboratory for Translational Neurogenetics, Trento, Italy
| | - Sven W. Sauer
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
| | - Thomas Opladen
- University Children's Hospital, Division of Child Neurology and Metabolic Diseases, Heidelberg, Germany
- * E-mail:
| |
Collapse
|
13
|
Fuentes R, Letelier J, Tajer B, Valdivia LE, Mullins MC. Fishing forward and reverse: Advances in zebrafish phenomics. Mech Dev 2018; 154:296-308. [PMID: 30130581 PMCID: PMC6289646 DOI: 10.1016/j.mod.2018.08.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [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: 04/04/2018] [Revised: 08/06/2018] [Accepted: 08/17/2018] [Indexed: 12/15/2022]
Abstract
Understanding how the genome instructs the phenotypic characteristics of an organism is one of the major scientific endeavors of our time. Advances in genetics have progressively deciphered the inheritance, identity and biological relevance of genetically encoded information, contributing to the rise of several, complementary omic disciplines. One of them is phenomics, an emergent area of biology dedicated to the systematic multi-scale analysis of phenotypic traits. This discipline provides valuable gene function information to the rapidly evolving field of genetics. Current molecular tools enable genome-wide analyses that link gene sequence to function in multi-cellular organisms, illuminating the genome-phenome relationship. Among vertebrates, zebrafish has emerged as an outstanding model organism for high-throughput phenotyping and modeling of human disorders. Advances in both systematic mutagenesis and phenotypic analyses of embryonic and post-embryonic stages in zebrafish have revealed the function of a valuable collection of genes and the general structure of several complex traits. In this review, we summarize multiple large-scale genetic efforts addressing parental, embryonic, and adult phenotyping in the zebrafish. The genetic and quantitative tools available in the zebrafish model, coupled with the broad spectrum of phenotypes that can be assayed, make it a powerful model for phenomics, well suited for the dissection of genotype-phenotype associations in development, physiology, health and disease.
Collapse
Affiliation(s)
- Ricardo Fuentes
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joaquín Letelier
- Centro Andaluz de Biología del Desarrollo (CSIC/UPO/JA), Seville, Spain; Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Benjamin Tajer
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Leonardo E Valdivia
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile.
| | - Mary C Mullins
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
14
|
Sawada R, Aramaki T, Kondo S. Flexibility of pigment cell behavior permits the robustness of skin pattern formation. Genes Cells 2018; 23:537-545. [PMID: 29797484 DOI: 10.1111/gtc.12596] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [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: 03/09/2018] [Accepted: 04/24/2018] [Indexed: 12/16/2022]
Abstract
The striped pigmentation pattern of zebrafish is determined by the interaction between pigment cells with different colors. Recent studies show the behaviors of pigment cells are substantially different according to the environment. Interestingly, the resulting patterns are almost identical, suggesting a robustness of the patterning mechanism. To know how this robustness originates, we investigated the behavior of melanophores in various environments including different developmental stages, different body positions, and different genetic backgrounds. Normally, when embryonic melanophores are excluded from the yellow stripe region in the body trunk, two different cellular behaviors are observed. Melanophores migrate to join the black stripe or disappear (die) in the position. In environments where melanophore migration was restricted, we observed that most melanophores disappeared in their position, resulting in the complete exclusion of melanophores from the yellow stripe. In environments where melanophore cell death was restricted, most melanophores migrated to join the black stripes, also resulting in complete exclusion. When both migration and cell death were restricted, melanophores remained alive in the yellow stripes. These results show that migration and cell death complement each other to achieve the exclusion of melanophores. This flexibility may be the basis of the mechanistic robustness of skin pattern formation.
Collapse
Affiliation(s)
- Risa Sawada
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Toshihiro Aramaki
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Shigeru Kondo
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| |
Collapse
|
15
|
Abstract
Teleost fish provide some of the most intriguing examples of sexually dimorphic coloration, which is often advantageous for only one of the sexes. Mapping studies demonstrated that the genetic loci underlying such color patterns are frequently in tight linkage to the sex-determining locus of a species, ensuring sex-specific expression of the corresponding trait. Several genes affecting color synthesis and pigment cell development have been previously described, but the color loci on the sex chromosomes have mostly remained elusive as yet. Here, we summarize the current knowledge about the genetics of such color loci in teleosts, mainly from studies on poeciliids and cichlids. Further studies on these color loci will certainly provide important insights into the evolution of sex chromosomes.
Collapse
|
16
|
Silvent J, Akiva A, Brumfeld V, Reznikov N, Rechav K, Yaniv K, Addadi L, Weiner S. Zebrafish skeleton development: High resolution micro-CT and FIB-SEM block surface serial imaging for phenotype identification. PLoS One 2017; 12:e0177731. [PMID: 29220379 DOI: 10.1371/journal.pone.0177731] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 05/02/2017] [Indexed: 12/03/2022] Open
Abstract
Although bone is one of the most studied living materials, many questions about the manner in which bones form remain unresolved, including fine details of the skeletal structure during development. In this study, we monitored skeleton development of zebrafish larvae, using calcein fluorescence, high-resolution micro-CT 3D images and FIB-SEM in the block surface serial imaging mode. We compared calcein staining of the skeletons of the wild type and nacre mutants, which are transparent zebrafish, with micro-CT for the first 30 days post fertilization embryos, and identified significant differences. We quantified the bone volumes and mineral contents of bones, including otoliths, during development, and showed that such developmental differences, including otolith development, could be helpful in identifying phenotypes. In addition, high-resolution imaging revealed the presence of mineralized aggregates in the notochord, before the formation of the first bone in the axial skeleton. These structures might play a role in the storage of the mineral. Our results highlight the potential of these high-resolution 3D approaches to characterize the zebrafish skeleton, which in turn could prove invaluable information for better understanding the development and the characterization of skeletal phenotypes.
Collapse
|
17
|
Roy SD, Williams VC, Pipalia TG, Li K, Hammond CL, Knappe S, Knight RD, Hughes SM. Myotome adaptability confers developmental robustness to somitic myogenesis in response to fibre number alteration. Dev Biol 2017; 431:321-335. [PMID: 28887016 PMCID: PMC5667637 DOI: 10.1016/j.ydbio.2017.08.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/22/2017] [Accepted: 08/26/2017] [Indexed: 12/31/2022]
Abstract
Balancing the number of stem cells and their progeny is crucial for tissue development and repair. Here we examine how cell numbers and overall muscle size are tightly regulated during zebrafish somitic muscle development. Muscle stem/precursor cell (MPCs) expressing Pax7 are initially located in the dermomyotome (DM) external cell layer, adopt a highly stereotypical distribution and thereafter a proportion of MPCs migrate into the myotome. Regional variations in the proliferation and terminal differentiation of MPCs contribute to growth of the myotome. To probe the robustness of muscle size control and spatiotemporal regulation of MPCs, we compared the behaviour of wild type (wt) MPCs with those in mutant zebrafish that lack the muscle regulatory factor Myod. Myodfh261 mutants form one third fewer multinucleate fast muscle fibres than wt and show a significant expansion of the Pax7+ MPC population in the DM. Subsequently, myodfh261 mutant fibres generate more cytoplasm per nucleus, leading to recovery of muscle bulk. In addition, relative to wt siblings, there is an increased number of MPCs in myodfh261 mutants and these migrate prematurely into the myotome, differentiate and contribute to the hypertrophy of existing fibres. Thus, homeostatic reduction of the excess MPCs returns their number to normal levels, but fibre numbers remain low. The GSK3 antagonist BIO prevents MPC migration into the deep myotome, suggesting that canonical Wnt pathway activation maintains the DM in zebrafish, as in amniotes. BIO does not, however, block recovery of the myodfh261 mutant myotome, indicating that homeostasis acts on fibre intrinsic growth to maintain muscle bulk. The findings suggest the existence of a critical window for early fast fibre formation followed by a period in which homeostatic mechanisms regulate myotome growth by controlling fibre size. The feedback controls we reveal in muscle help explain the extremely precise grading of myotome size along the body axis irrespective of fish size, nutrition and genetic variation and may form a paradigm for wider matching of organ size. A critical window for early muscle fibre formation is proposed. Fish lacking MyoD1 form fewer muscle fibres, but have more myogenic stem cells. Stem cell numbers rapidly return to normal during subsequent development. GSK3 activity promotes and MyoD1 delays myoblast migration into the myotome. Compensatory fibre size increase ensures robustness of overall muscle size.
Collapse
Affiliation(s)
- Shukolpa D Roy
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Victoria C Williams
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Tapan G Pipalia
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Kuoyu Li
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Christina L Hammond
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Stefanie Knappe
- Division of Craniofacial Development and Stem Cell Biology, Guy's Hospital, King's College London, UK
| | - Robert D Knight
- Division of Craniofacial Development and Stem Cell Biology, Guy's Hospital, King's College London, UK
| | - Simon M Hughes
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London SE1 1UL, UK.
| |
Collapse
|
18
|
van Rooijen E, Fazio M, Zon LI. From fish bowl to bedside: The power of zebrafish to unravel melanoma pathogenesis and discover new therapeutics. Pigment Cell Melanoma Res 2017; 30:402-412. [PMID: 28379616 PMCID: PMC6038924 DOI: 10.1111/pcmr.12592] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [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: 02/03/2017] [Accepted: 03/22/2017] [Indexed: 12/28/2022]
Abstract
Melanoma is the most aggressive and deadliest form of skin cancer. A detailed knowledge of the cellular, molecular, and genetic events underlying melanoma progression is highly relevant to diagnosis, prognosis and risk stratification, and the development of new therapies. In the last decade, zebrafish have emerged as a valuable model system for the study of melanoma. Pathway conservation, coupled with the availability of robust genetic, transgenic, and chemical tools, has made the zebrafish a powerful model for identifying novel disease genes, visualizing cancer initiation, interrogating tumor-microenvironment interactions, and discovering new therapeutics that regulate melanocyte and melanoma development. In this review, we will give an overview of these studies, and highlight recent advancements that will help unravel melanoma pathogenesis and impact human disease.
Collapse
Affiliation(s)
- Ellen van Rooijen
- Stem Cell Program and Division of Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| | - Maurizio Fazio
- Stem Cell Program and Division of Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
- PhD program in Biological and Biomedical Sciences, Harvard University, Boston, MA, USA
| | - Leonard I. Zon
- Stem Cell Program and Division of Hematology/Oncology, Boston Children’s Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
19
|
Eskova A, Chauvigné F, Maischein HM, Ammelburg M, Cerdà J, Nüsslein-Volhard C, Irion U. Gain-of-function mutations in Aqp3a influence zebrafish pigment pattern formation through the tissue environment. Development 2017; 144:2059-2069. [PMID: 28506994 PMCID: PMC5482984 DOI: 10.1242/dev.143495] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 04/24/2017] [Indexed: 01/26/2023]
Abstract
The development of the pigmentation pattern in zebrafish is a tightly regulated process that depends on both the self-organizing properties of pigment cells and extrinsic cues from other tissues. Many of the known mutations that alter the pattern act cell-autonomously in pigment cells, and our knowledge about external regulators is limited. Here, we describe novel zebrafish mau mutants, which encompass several dominant missense mutations in Aquaporin 3a (Aqp3a) that lead to broken stripes and short fins. A loss-of-function aqp3a allele, generated by CRISPR-Cas9, has no phenotypic consequences, demonstrating that Aqp3a is dispensable for normal development. Strikingly, the pigment cells from dominant mau mutants are capable of forming a wild-type pattern when developing in a wild-type environment, but the surrounding tissues in the mutants influence pigment cell behaviour and interfere with the patterning process. The mutated amino acid residues in the dominant alleles line the pore surface of Aqp3a and influence pore permeability. These results demonstrate an important effect of the tissue environment on pigment cell behaviour and, thereby, on pattern formation. Summary: Dominant mutations in the water channel Aquaporin 3a cause defective pigment patterning in zebrafish, due at least in part to an effect of the mutant tissue environment on the pigment cells.
Collapse
Affiliation(s)
- Anastasia Eskova
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Francois Chauvigné
- IRTA-Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), 08003 Barcelona, Spain
| | | | - Moritz Ammelburg
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| | - Joan Cerdà
- IRTA-Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), 08003 Barcelona, Spain
| | | | - Uwe Irion
- Max Planck Institute for Developmental Biology, 72076 Tübingen, Germany
| |
Collapse
|
20
|
Kim DC, Kim S, Hwang KS, Kim CH. p-Coumaric Acid Potently Down-regulates Zebrafish Embryo Pigmentation: Comparison ofin vivoAssay and Computational Molecular Modeling with Phenylthiourea. ACTA ACUST UNITED AC 2017. [DOI: 10.15616/bsl.2017.23.1.8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Dong-Chan Kim
- Department of Biomedical Laboratory Science, Gimcheon University, Gimcheon 39528, Korea
| | - Seonlin Kim
- Department of Novel Drug Design Laboratory, Neuronex, Goryeong 40152, Korea
| | - Kyu-Seok Hwang
- Department of Biology, Chungnam National University, Daejeon 34134, Korea
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon 34134, Korea
| |
Collapse
|
21
|
Pipalia TG, Koth J, Roy SD, Hammond CL, Kawakami K, Hughes SM. Cellular dynamics of regeneration reveals role of two distinct Pax7 stem cell populations in larval zebrafish muscle repair. Dis Model Mech 2016; 9:671-84. [PMID: 27149989 PMCID: PMC4920144 DOI: 10.1242/dmm.022251] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 04/27/2016] [Indexed: 12/25/2022] Open
Abstract
Heterogeneity of stem cells or their niches is likely to influence tissue regeneration. Here we reveal stem/precursor cell diversity during wound repair in larval zebrafish somitic body muscle using time-lapse 3D confocal microscopy on reporter lines. Skeletal muscle with incision wounds rapidly regenerates both slow and fast muscle fibre types. A swift immune response is followed by an increase in cells at the wound site, many of which express the muscle stem cell marker Pax7. Pax7(+) cells proliferate and then undergo terminal differentiation involving Myogenin accumulation and subsequent loss of Pax7 followed by elongation and fusion to repair fast muscle fibres. Analysis of pax7a and pax7b transgenic reporter fish reveals that cells expressing each of the duplicated pax7 genes are distinctly localised in uninjured larvae. Cells marked by pax7a only or by both pax7a and pax7b enter the wound rapidly and contribute to muscle wound repair, but each behaves differently. Low numbers of pax7a-only cells form nascent fibres. Time-lapse microscopy revealed that the more numerous pax7b-marked cells frequently fuse to pre-existing fibres, contributing more strongly than pax7a-only cells to repair of damaged fibres. pax7b-marked cells are more often present in rows of aligned cells that are observed to fuse into a single fibre, but more rarely contribute to nascent regenerated fibres. Ablation of a substantial portion of nitroreductase-expressing pax7b cells with metronidazole prior to wounding triggered rapid pax7a-only cell accumulation, but this neither inhibited nor augmented pax7a-only cell-derived myogenesis and thus altered the cellular repair dynamics during wound healing. Moreover, pax7a-only cells did not regenerate pax7b cells, suggesting a lineage distinction. We propose a modified founder cell and fusion-competent cell model in which pax7a-only cells initiate fibre formation and pax7b cells contribute to fibre growth. This newly discovered cellular complexity in muscle wound repair raises the possibility that distinct populations of myogenic cells contribute differentially to repair in other vertebrates.
Collapse
Affiliation(s)
- Tapan G Pipalia
- Randall Division of Cell and Molecular Biophysics, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Jana Koth
- Randall Division of Cell and Molecular Biophysics, Guy's Campus, King's College London, London SE1 1UL, UK Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford University, Oxford OX3 9DS, UK
| | - Shukolpa D Roy
- Randall Division of Cell and Molecular Biophysics, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Christina L Hammond
- Randall Division of Cell and Molecular Biophysics, Guy's Campus, King's College London, London SE1 1UL, UK
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, and Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, Shizuoka 411-8540, Japan
| | - Simon M Hughes
- Randall Division of Cell and Molecular Biophysics, Guy's Campus, King's College London, London SE1 1UL, UK
| |
Collapse
|
22
|
Nord H, Dennhag N, Muck J, von Hofsten J. Pax7 is required for establishment of the xanthophore lineage in zebrafish embryos. Mol Biol Cell 2016; 27:1853-62. [PMID: 27053658 PMCID: PMC4884075 DOI: 10.1091/mbc.e15-12-0821] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [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: 12/07/2015] [Accepted: 04/01/2016] [Indexed: 11/11/2022] Open
Abstract
A conceptually novel role for Pax7 is found in zebrafish pigment formation. Absence of Pax7 leads to an expansion of the embryonic and larval melanophore lineage and a depletion of xanthophores, suggesting a model in which Pax7 is involved in early chromatophore specification processes. The pigment pattern of many animal species is a result of the arrangement of different types of pigment-producing chromatophores. The zebrafish has three different types of chromatophores: black melanophores, yellow xanthophores, and shimmering iridophores arranged in a characteristic pattern of golden and blue horizontal stripes. In the zebrafish embryo, chromatophores derive from the neural crest cells. Using pax7a and pax7b zebrafish mutants, we identified a previously unknown requirement for Pax7 in xanthophore lineage formation. The absence of Pax7 results in a severe reduction of xanthophore precursor cells and a complete depletion of differentiated xanthophores in embryos as well as in adult zebrafish. In contrast, the melanophore lineage is increased in pax7a/pax7b double-mutant embryos and larvae, whereas juvenile and adult pax7a/pax7b double-mutant zebrafish display a severe decrease in melanophores and a pigment pattern disorganization indicative of a xanthophore- deficient phenotype. In summary, we propose a novel role for Pax7 in the early specification of chromatophore precursor cells.
Collapse
Affiliation(s)
- Hanna Nord
- Umeå Centre for Molecular Medicine, Umeå University, 90187 Umeå, Sweden
| | - Nils Dennhag
- Umeå Centre for Molecular Medicine, Umeå University, 90187 Umeå, Sweden
| | - Joscha Muck
- Umeå Centre for Molecular Medicine, Umeå University, 90187 Umeå, Sweden Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
| | - Jonas von Hofsten
- Umeå Centre for Molecular Medicine, Umeå University, 90187 Umeå, Sweden Department for Integrative Medical Biology, Umeå University, 90187 Umeå, Sweden
| |
Collapse
|
23
|
|
24
|
Giles AC, Opperman KJ, Rankin CH, Grill B. Developmental Function of the PHR Protein RPM-1 Is Required for Learning in Caenorhabditis elegans. G3 (Bethesda) 2015; 5:2745-57. [PMID: 26464359 PMCID: PMC4683646 DOI: 10.1534/g3.115.021410] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [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] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/06/2015] [Indexed: 12/12/2022]
Abstract
The PAM/Highwire/RPM-1 (PHR) proteins are signaling hubs that function as important regulators of neural development. Loss of function in Caenorhabditis elegans rpm-1 and Drosophila Highwire results in failed axon termination, inappropriate axon targeting, and abnormal synapse formation. Despite broad expression in the nervous system and relatively dramatic defects in synapse formation and axon development, very mild abnormalities in behavior have been found in animals lacking PHR protein function. Therefore, we hypothesized that large defects in behavior might only be detected in scenarios in which evoked, prolonged circuit function is required, or in which behavioral plasticity occurs. Using quantitative approaches in C. elegans, we found that rpm-1 loss-of-function mutants have relatively mild abnormalities in exploratory locomotion, but have large defects in evoked responses to harsh touch and learning associated with tap habituation. We explored the nature of the severe habituation defects in rpm-1 mutants further. To address what part of the habituation circuit was impaired in rpm-1 mutants, we performed rescue analysis with promoters for different neurons. Our findings indicate that RPM-1 function in the mechanosensory neurons affects habituation. Transgenic expression of RPM-1 in adult animals failed to rescue habituation defects, consistent with developmental defects in rpm-1 mutants resulting in impaired habituation. Genetic analysis showed that other regulators of neuronal development that function in the rpm-1 pathway (including glo-4, fsn-1, and dlk-1) also affected habituation. Overall, our findings suggest that developmental defects in rpm-1 mutants manifest most prominently in behaviors that require protracted or plastic circuit function, such as learning.
Collapse
Affiliation(s)
- Andrew C Giles
- Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458
| | - Karla J Opperman
- Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458
| | - Catharine H Rankin
- Department of Psychology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada Brain Research Centre, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada
| | - Brock Grill
- Department of Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458
| |
Collapse
|
25
|
Abstract
Colour patterns are prominent features of many animals and have important functions in communication, such as camouflage, kin recognition and mate choice. As targets for natural as well as sexual selection, they are of high evolutionary significance. The molecular mechanisms underlying colour pattern formation in vertebrates are not well understood. Progress in transgenic tools, in vivo imaging and the availability of a large collection of mutants make the zebrafish (Danio rerio) an attractive model to study vertebrate colouration. Zebrafish display golden and blue horizontal stripes that form during metamorphosis as mosaics of yellow xanthophores, silvery or blue iridophores and black melanophores in the hypodermis. Lineage tracing revealed the origin of the adult pigment cells and their individual cellular behaviours during the formation of the striped pattern. Mutant analysis indicated that interactions between all three pigment cell types are required for the formation of the pattern, and a number of cell surface molecules and signalling systems have been identified as mediators of these interactions. The understanding of the mechanisms that underlie colour pattern formation is an important step towards deciphering the genetic basis of variation in evolution.
Collapse
|
26
|
Li XM, Song YN, Xiao GB, Zhu BH, Xu GC, Sun MY, Xiao J, Mahboob S, Al-Ghanim KA, Sun XW, Li JT. Gene Expression Variations of Red-White Skin Coloration in Common Carp (Cyprinus carpio). Int J Mol Sci 2015; 16:21310-29. [PMID: 26370964 PMCID: PMC4613254 DOI: 10.3390/ijms160921310] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/14/2015] [Accepted: 08/25/2015] [Indexed: 01/12/2023] Open
Abstract
Teleosts have more types of chromatophores than other vertebrates and the genetic basis for pigmentation is highly conserved among vertebrates. Therefore, teleosts are important models to study the mechanism of pigmentation. Although functional genes and genetic variations of pigmentation have been studied, the mechanisms of different skin coloration remains poorly understood. The koi strain of common carp has various colors and patterns, making it a good model for studying the genetic basis of pigmentation. We performed RNA-sequencing for red skin and white skin and identified 62 differentially expressed genes (DEGs). Most of them were validated with RT-qPCR. The up-regulated DEGs in red skin were enriched in Kupffer's vesicle development while the up-regulated DEGs in white skin were involved in cytoskeletal protein binding, sarcomere organization and glycogen phosphorylase activity. The distinct enriched activity might be associated with different structures and functions in erythrophores and iridophores. The DNA methylation levels of two selected DEGs inversely correlated with gene expression, indicating the participation of DNA methylation in the coloration. This expression characterization of red-white skin along with the accompanying transcriptome-wide expression data will be a useful resource for further studies of pigment cell biology.
Collapse
Affiliation(s)
- Xiao-Min Li
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
| | - Ying-Nan Song
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
| | - Gui-Bao Xiao
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
| | - Bai-Han Zhu
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
| | - Gui-Cai Xu
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
| | - Ming-Yuan Sun
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
| | - Jun Xiao
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China.
| | - Shahid Mahboob
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Khalid A Al-Ghanim
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Xiao-Wen Sun
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
| | - Jiong-Tang Li
- CAFS Key Laboratory of Aquatic Genomics and Beijing Key Laboratory of Fishery Biotechnology, Centre for Applied Aquatic Genomics, Chinese Academy of Fishery Sciences, Beijing 10014, China.
| |
Collapse
|
27
|
Knappe S, Zammit PS, Knight RD. A population of Pax7-expressing muscle progenitor cells show differential responses to muscle injury dependent on developmental stage and injury extent. Front Aging Neurosci 2015; 7:161. [PMID: 26379543 PMCID: PMC4548158 DOI: 10.3389/fnagi.2015.00161] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 08/06/2015] [Indexed: 02/03/2023] Open
Abstract
Skeletal muscle regeneration in vertebrates occurs by the activation of quiescent progenitor cells that express pax7 to repair and replace damaged myofibers. We have developed a mechanical injury paradigm in zebrafish to determine whether developmental stage and injury size affect the regeneration dynamics of skeletal muscle. We found that both small focal injuries, and large injuries affecting the entire myotome, lead to expression of myf5 and myogenin, which was prolonged in older larvae, indicating a slower process of regeneration. We characterized the endogenous behavior of a population of muscle-resident Pax7-expressing cells using a pax7a:eGFP transgenic line and found that GFP+ cell migration in the myotome dramatically declined between 5 and 7 days post-fertilization (dpf). Following a small single myotome injury, GFP+ cells responded by extending processes, before migrating to the injured myofibers. Furthermore, these cells responded more rapidly to injury in 4 dpf larvae compared to 7 dpf. Interestingly, we did not see GFP+ myofibers after repair of small injuries, indicating that pax7a-expressing cells did not contribute to myofiber formation in this injury context. On the contrary, numerous GFP+ myofibers could be observed after an extensive single myotome injury. Both injury models were accompanied by an increased number of proliferating GFP+ cells, which was more pronounced in larvae injured at 4 dpf than 7 dpf. This indicates intriguing developmental differences, at these early ages. Our data also suggests an interesting disparity in the role that pax7a-expressing muscle progenitor cells play during skeletal muscle regeneration, which may reflect the extent of muscle damage.
Collapse
Affiliation(s)
- Stefanie Knappe
- Department of Craniofacial Development and Stem Cell Biology, Dental Institute, King's College London London, UK
| | - Peter S Zammit
- Randall Division of Cell and Molecular Biophysics, Faculty of Life Sciences and Medicine, King's College London London, UK
| | - Robert D Knight
- Department of Craniofacial Development and Stem Cell Biology, Dental Institute, King's College London London, UK
| |
Collapse
|
28
|
Fadeev A, Krauss J, Frohnhöfer HG, Irion U, Nüsslein-Volhard C. Tight Junction Protein 1a regulates pigment cell organisation during zebrafish colour patterning. eLife 2015; 4. [PMID: 25915619 PMCID: PMC4446668 DOI: 10.7554/elife.06545] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 04/24/2015] [Indexed: 01/21/2023] Open
Abstract
Zebrafish display a prominent pattern of alternating dark and light stripes generated by the precise positioning of pigment cells in the skin. This arrangement is the result of coordinated cell movements, cell shape changes, and the organisation of pigment cells during metamorphosis. Iridophores play a crucial part in this process by switching between the dense form of the light stripes and the loose form of the dark stripes. Adult schachbrett (sbr) mutants exhibit delayed changes in iridophore shape and organisation caused by truncations in Tight Junction Protein 1a (ZO-1a). In sbr mutants, the dark stripes are interrupted by dense iridophores invading as coherent sheets. Immuno-labelling and chimeric analyses indicate that Tjp1a is expressed in dense iridophores but down-regulated in the loose form. Tjp1a is a novel regulator of cell shape changes during colour pattern formation and the first cytoplasmic protein implicated in this process. DOI:http://dx.doi.org/10.7554/eLife.06545.001 The striking horizontal striped pattern of the zebrafish makes it a decorative addition to many home aquariums. The stripes are a result of three different pigment cells interacting with each other, and first begin to emerge when the animal is two to three weeks old. At that time, iridescent cells called iridophores begin to multiply and spread in the skin. In the light-coloured stripes, the iridophores are compact and ‘dense’; in the dark stripes the cells change into a ‘loose’ shape and organisation. Black-pigmented cells fill in the dark stripes, and a third cell type with a yellow hue condenses over the light stripes. How the three types of cell work together to make the striped pattern is not fully understood. Fadeev et al. examined a zebrafish variant with a genetic mutation that disrupts the function of a protein called Tight Junction Protein 1a (or Tjp1a)—a fish variant of a mammalian protein called ZO-1. This protein helps cells to interact with each other. The mutant fish appear spotted rather than striped, because light regions containing sheets of the dense iridophores interrupt the dark stripes. Experiments using fluorescent markers showed that Tjp1a is produced in much lower amounts in the loose iridophores in the dark stripes than in the dense iridophores of the light stripes. This led Fadeev et al. to suggest that the transition from the dense to the loose shape is dependent on the presence of Tjp1a in the cell. Tjp1a is likely to regulate how colour patterns form by controlling how iridophores interact with other types of pigment cell. The Tjp1a mutant fish provides the first glimpse into the machinery inside cells that underlies colour pattern formation, and will help to identify other components and cues responsible for cell interactions. DOI:http://dx.doi.org/10.7554/eLife.06545.002
Collapse
Affiliation(s)
- Andrey Fadeev
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | - Jana Krauss
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | - Uwe Irion
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | |
Collapse
|
29
|
Affiliation(s)
- Verena A. Kottler
- Department of Molecular Biology; Max Planck Institute for Developmental Biology; Tübingen Germany
| | - Axel Künstner
- Department of Molecular Biology; Max Planck Institute for Developmental Biology; Tübingen Germany
- Guest Group Evolutionary Genomics; Max Planck Institute for Evolutionary Biology; Plön Germany
- Lübeck Institute of Experimental Dermatology; University of Lübeck; Lübeck Germany
| | - Manfred Schartl
- Department of Physiological Chemistry, Biocenter; University of Würzburg; Würzburg Germany
- Comprehensive Cancer Center Mainfranken; University Clinic Würzburg; Würzburg Germany
| |
Collapse
|
30
|
Kratochwil CF, Sefton MM, Meyer A. Embryonic and larval development in the Midas cichlid fish species flock (Amphilophus spp.): a new evo-devo model for the investigation of adaptive novelties and species differences. BMC Dev Biol 2015; 15:12. [PMID: 25887993 PMCID: PMC4352272 DOI: 10.1186/s12861-015-0061-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 02/16/2015] [Indexed: 02/07/2023]
Abstract
Background Central American crater lake cichlid fish of the Midas species complex (Amphilophus spp.) are a model system for sympatric speciation and fast ecological diversification and specialization. Midas cichlids have been intensively analyzed from an ecological and morphological perspective. Genomic resources such as transcriptomic and genomic data sets, and a high-quality draft genome are available now. Many ecologically relevant species-specific traits and differences such as pigmentation and cranial morphology arise during development. Detailed descriptions of the early development of the Midas cichlid in particular, will help to investigate the ontogeny of species differences and adaptations. Results We describe the embryonic and larval development of the crater lake cichlid, Amphilophus xiloaensis, until seven days after fertilization. Similar to previous studies on teleost development, we describe six periods of embryogenesis - the zygote, cleavage, blastula, gastrula, segmentation, and post-hatching period. Furthermore, we define homologous stages to well-described teleost models such as medaka and zebrafish, as well as other cichlid species such as the Nile tilapia and the South American cichlid Cichlasoma dimerus. Key morphological differences between the embryos of Midas cichlids and other teleosts are highlighted and discussed, including the presence of adhesive glands and different early chromatophore patterns, as well as variation in developmental timing. Conclusions The developmental staging of the Midas cichlid will aid researchers in the comparative investigation of teleost ontogenies. It will facilitate comparative developmental biological studies of Neotropical and African cichlid fish in particular. In the past, the species flocks of the African Great Lakes have received the most attention from researchers, but some lineages of the 300–400 species of Central American lakes are fascinating model systems for adaptive radiation and rapid phenotypic evolution. The availability of genetic resources, their status as a model system for evolutionary research, and the possibility to perform functional experiments including transgenesis makes the Midas cichlid complex a very attractive model for evolutionary-developmental research.
Collapse
Affiliation(s)
- Claudius F Kratochwil
- Zoology and Evolutionary Biology, Department of Biology, University of Konstanz, Konstanz, Germany. .,Zukunftskolleg, University of Konstanz, Konstanz, Germany.
| | - Maggie M Sefton
- Zoology and Evolutionary Biology, Department of Biology, University of Konstanz, Konstanz, Germany. .,International Max Planck Research School for Organismal Biology, University of Konstanz, Konstanz, Germany.
| | - Axel Meyer
- Zoology and Evolutionary Biology, Department of Biology, University of Konstanz, Konstanz, Germany. .,International Max Planck Research School for Organismal Biology, University of Konstanz, Konstanz, Germany.
| |
Collapse
|
31
|
Watanabe M, Kondo S. Is pigment patterning in fish skin determined by the Turing mechanism? Trends Genet 2015; 31:88-96. [DOI: 10.1016/j.tig.2014.11.005] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 11/14/2014] [Accepted: 11/17/2014] [Indexed: 11/18/2022]
|
32
|
Irion U, Frohnhöfer HG, Krauss J, Çolak Champollion T, Maischein HM, Geiger-Rudolph S, Weiler C, Nüsslein-Volhard C. Gap junctions composed of connexins 41.8 and 39.4 are essential for colour pattern formation in zebrafish. eLife 2014; 3:e05125. [PMID: 25535837 PMCID: PMC4296512 DOI: 10.7554/elife.05125] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 12/22/2014] [Indexed: 11/20/2022] Open
Abstract
Interactions between all three pigment cell types are required to form the stripe pattern of adult zebrafish (Danio rerio), but their molecular nature is poorly understood. Mutations in leopard (leo), encoding Connexin 41.8 (Cx41.8), a gap junction subunit, cause a phenotypic series of spotted patterns. A new dominant allele, leotK3, leads to a complete loss of the pattern, suggesting a dominant negative impact on another component of gap junctions. In a genetic screen, we identified this component as Cx39.4 (luchs). Loss-of-function alleles demonstrate that luchs is required for stripe formation in zebrafish; however, the fins are almost not affected. Double mutants and chimeras, which show that leo and luchs are only required in xanthophores and melanophores, but not in iridophores, suggest that both connexins form heteromeric gap junctions. The phenotypes indicate that these promote homotypic interactions between melanophores and xanthophores, respectively, and those cells instruct the patterning of the iridophores. DOI:http://dx.doi.org/10.7554/eLife.05125.001 The colour patterns that mark an animal's skin, hair, or feathers—called the pigmentation pattern—can be very important for its survival and fitness, helping it to hide from predators or to attract a mate. As a result, there is considerable interest in understanding how genes, proteins, and cells work together to produce the many different pigmentation patterns that exist in the animal world. Adult zebrafish have a characteristic pigmentation pattern of horizontal dark and light stripes on their bodies and fins. There are three types of pigment cell that create this pattern. Xanthophores and iridophores are found all over the body, and the dark stripes also contain melanophore cells. The silvery, reflective iridophores are the first of the cells to populate the skin, giving rise to the first light stripe. They then form a dense network of cells that breaks up to form the darker stripes. However, iridophores are not required to form stripes in the fins, suggesting that patterning occurs differently in the fins and the body. Mutations to a gene called leopard, or leo for short, cause spots to form on the skin of the zebrafish in place of the usual stripes. This gene encodes a member of the connexin family of proteins, which form channels in the membranes that surround cells. These channels—known as gap junctions—allow neighbouring cells to communicate with each other. Each gap junction is made up of two half channels, with one half coming from each neighbouring cells. If the two half channels are identical, the gap junction is known as ‘homomeric’; ‘heteromeric’ gap junctions are made from two different half channels, each consisting of a different connexin protein. The connexin encoded by leo is required for both types of gap junction to form between melanophores and xanthophores. Irion et al. discovered a new mutation to the leo gene that completely disrupts the patterning of the zebrafish. A technique called a genetic screen revealed that the same patterning defects are also seen in the body of zebrafish with mutations to another gene called luchs, which encodes a different connexin protein to the one produced by leo. However, the fins of zebrafish with mutant versions of luchs remain striped. The findings of Irion et al. suggest that heteromeric gap junctions formed from the connexins produced by leo and luchs are important for xanthophores and melanophores to communicate with each other and so form the stripy patterning seen on the body of the zebrafish. The signals transmitted through the gap junctions may also make the iridophores adopt the looser arrangement that is required for the dark stripes to form. As a next step, it will be important to identify the signals that pass through these gap junctions that allow the cells to communicate with their neighbours and establish the pigmentation pattern. DOI:http://dx.doi.org/10.7554/eLife.05125.002
Collapse
Affiliation(s)
- Uwe Irion
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | - Jana Krauss
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | | | | | | - Christian Weiler
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| | | |
Collapse
|
33
|
Parichy DM, Spiewak JE. Origins of adult pigmentation: diversity in pigment stem cell lineages and implications for pattern evolution. Pigment Cell Melanoma Res 2014; 28:31-50. [PMID: 25421288 DOI: 10.1111/pcmr.12332] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [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: 09/24/2014] [Accepted: 11/20/2014] [Indexed: 12/25/2022]
Abstract
Teleosts comprise about half of all vertebrate species and exhibit an extraordinary diversity of adult pigment patterns that function in shoaling, camouflage, and mate choice and have played important roles in speciation. Here, we review studies that have identified several distinct neural crest lineages, with distinct genetic requirements, that give rise to adult pigment cells in fishes. These lineages include post-embryonic, peripheral nerve-associated stem cells that generate black melanophores and iridescent iridophores, cells derived directly from embryonic neural crest cells that generate yellow-orange xanthophores, and bipotent stem cells that generate both melanophores and xanthophores. This complexity in adult chromatophore lineages has implications for our understanding of adult traits, melanoma, and the evolutionary diversification of pigment cell lineages and patterns.
Collapse
Affiliation(s)
- David M Parichy
- Department of Biology, University of Washington, Seattle, WA, USA
| | | |
Collapse
|
34
|
|
35
|
Mahalwar P, Walderich B, Singh AP, Nusslein-Volhard C. Local reorganization of xanthophores fine-tunes and colors the striped pattern of zebrafish. Science 2014; 345:1362-4. [DOI: 10.1126/science.1254837] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
36
|
Singh AP, Schach U, Nüsslein-Volhard C. Proliferation, dispersal and patterned aggregation of iridophores in the skin prefigure striped colouration of zebrafish. Nat Cell Biol 2014; 16:607-14. [DOI: 10.1038/ncb2955] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 03/20/2014] [Indexed: 12/20/2022]
|
37
|
Nagao Y, Suzuki T, Shimizu A, Kimura T, Seki R, Adachi T, Inoue C, Omae Y, Kamei Y, Hara I, Taniguchi Y, Naruse K, Wakamatsu Y, Kelsh RN, Hibi M, Hashimoto H. Sox5 functions as a fate switch in medaka pigment cell development. PLoS Genet 2014; 10:e1004246. [PMID: 24699463 PMCID: PMC3974636 DOI: 10.1371/journal.pgen.1004246] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 02/02/2014] [Indexed: 11/30/2022] Open
Abstract
Mechanisms generating diverse cell types from multipotent progenitors are crucial for normal development. Neural crest cells (NCCs) are multipotent stem cells that give rise to numerous cell-types, including pigment cells. Medaka has four types of NCC-derived pigment cells (xanthophores, leucophores, melanophores and iridophores), making medaka pigment cell development an excellent model for studying the mechanisms controlling specification of distinct cell types from a multipotent progenitor. Medaka many leucophores-3 (ml-3) mutant embryos exhibit a unique phenotype characterized by excessive formation of leucophores and absence of xanthophores. We show that ml-3 encodes sox5, which is expressed in premigratory NCCs and differentiating xanthophores. Cell transplantation studies reveal a cell-autonomous role of sox5 in the xanthophore lineage. pax7a is expressed in NCCs and required for both xanthophore and leucophore lineages; we demonstrate that Sox5 functions downstream of Pax7a. We propose a model in which multipotent NCCs first give rise to pax7a-positive partially fate-restricted intermediate progenitors for xanthophores and leucophores; some of these progenitors then express sox5, and as a result of Sox5 action develop into xanthophores. Our results provide the first demonstration that Sox5 can function as a molecular switch driving specification of a specific cell-fate (xanthophore) from a partially-restricted, but still multipotent, progenitor (the shared xanthophore-leucophore progenitor). How individual cell fates are specified from multipotent progenitor cells is a fundamental question in developmental and stem cell biology. Accumulating evidence indicates that stem cells develop into each of their final, diverse cell-types after progression through one or more partially-restricted intermediates, but the molecular mechanisms underlying final fate choice are largely unknown. Neural crest cells (NCCs) give rise to diverse cell-types including multiple pigment cells and thus are a favored model for understanding the mechanism of fate specification. We have investigated how a specific fate choice is made from partially-restricted pigment cell progenitors in medaka. We show that Sry-related transcription factor Sox5 is required for fate determination between yellow xanthophore and white leucophore, and its loss causes excessive formation of leucophores and absence of xanthophores. We demonstrate that Sox5 functions cell-autonomously in the xanthophore lineage in medaka. Furthermore, pax7a is expressed in the partially-restricted progenitor cells shared with xanthophore and leucophore lineages, and Sox5 acts in some of these cells to promote xanthophore lineage. Our work reveals the role of Sox5 as a molecular switch determining xanthophore versus leucophore fate choice from the shared progenitor, and identifies an important mechanism regulating pigment cell fate choice from NCCs.
Collapse
Affiliation(s)
- Yusuke Nagao
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Takao Suzuki
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Atsushi Shimizu
- Division of Biomedical Information Analysis, Iwate Tohoku Medical Megabank Organization, Iwate Medical University, Yahaba-cho, Shiwa-gun, Iwate, Japan
| | - Tetsuaki Kimura
- National Institute for Basic Biology, Interuniversity Bio-Backup Project Center, Okazaki, Aichi, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Myodaiji, Okazaki, Aichi, Japan
| | - Ryoko Seki
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Tomoko Adachi
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
- Centre for Regenerative Medicine and Department of Biology and Biochemistry, University of Bath, Bath, Claverton Down, United Kingdom
| | - Chikako Inoue
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Yoshihiro Omae
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Yasuhiro Kamei
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Myodaiji, Okazaki, Aichi, Japan
- Spectrography and Bioimaging Facility, National Institute for Basic Biology, Myodaiji, Okazaki, Aichi, Japan
| | - Ikuyo Hara
- Laboratory of Bioresources, National Institute for Basic Biology, Myodaiji, Okazaki, Aichi, Japan
| | - Yoshihito Taniguchi
- Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Shinjuku-ku, Tokyo, Japan
| | - Kiyoshi Naruse
- National Institute for Basic Biology, Interuniversity Bio-Backup Project Center, Okazaki, Aichi, Japan
- Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Myodaiji, Okazaki, Aichi, Japan
- Laboratory of Bioresources, National Institute for Basic Biology, Myodaiji, Okazaki, Aichi, Japan
| | - Yuko Wakamatsu
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Robert N. Kelsh
- Centre for Regenerative Medicine and Department of Biology and Biochemistry, University of Bath, Bath, Claverton Down, United Kingdom
| | - Masahiko Hibi
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
| | - Hisashi Hashimoto
- Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
- Bioscience and Biotechnology Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan
- * E-mail:
| |
Collapse
|
38
|
Hamada H, Watanabe M, Lau HE, Nishida T, Hasegawa T, Parichy DM, Kondo S. Involvement of Delta/Notch signaling in zebrafish adult pigment stripe patterning. Development 2013; 141:318-24. [PMID: 24306107 PMCID: PMC3879813 DOI: 10.1242/dev.099804] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The skin pigment pattern of zebrafish is a good model system in which to study the mechanism of biological pattern formation. Although it is known that interactions between melanophores and xanthophores play a key role in the formation of adult pigment stripes, molecular mechanisms for these interactions remain largely unknown. Here, we show that Delta/Notch signaling contributes to these interactions. Ablation of xanthophores in yellow stripes induced the death of melanophores in black stripes, suggesting that melanophores require a survival signal from distant xanthophores. We found that deltaC and notch1a were expressed by xanthophores and melanophores, respectively. Moreover, inhibition of Delta/Notch signaling killed melanophores, whereas activation of Delta/Notch signaling ectopically in melanophores rescued the survival of these cells, both in the context of pharmacological inhibition of Delta/Notch signaling and after ablation of xanthophores. Finally, we showed by in vivo imaging of cell membranes that melanophores extend long projections towards xanthophores in the yellow stripes. These data suggest that Delta/Notch signaling is responsible for a survival signal provided by xanthophores to melanophores. As cellular projections can enable long-range interaction between membrane-bound ligands and their receptors, we propose that such projections, combined with direct cell-cell contacts, can substitute for the effect of a diffusible factor that would be expected by the conventional reaction-diffusion (Turing) model.
Collapse
Affiliation(s)
- Hiroki Hamada
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | | | | | | | | | | | | |
Collapse
|
39
|
van der Velden YU, Wang L, Querol Cano L, Haramis AP. The polycomb group protein ring1b/rnf2 is specifically required for craniofacial development. PLoS One 2013; 8:e73997. [PMID: 24040141 DOI: 10.1371/journal.pone.0073997] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Accepted: 07/29/2013] [Indexed: 01/24/2023] Open
Abstract
Polycomb group (PcG) genes are chromatin modifiers that mediate epigenetic silencing of target genes. PcG-mediated epigenetic silencing is implicated in embryonic development, stem cell plasticity, cell fate maintenance, cellular differentiation and cancer. However, analysis of the roles of PcG proteins in maintaining differentiation programs during vertebrate embryogenesis has been hampered due to the early embryonic lethality of several PcG knock-outs in the mouse. Here, we show that zebrafish Ring1b/Rnf2, the single E3 ubiquitin ligase in the Polycomb Repressive Complex 1, critically regulates the developmental program of craniofacial cell lineages. Zebrafish ring1b mutants display a severe craniofacial phenotype, which includes an almost complete absence of all cranial cartilage, bone and musculature. We show that Cranial Neural Crest (CNC)-derived cartilage precursors migrate correctly into the pharyngeal arches, but fail to differentiate into chondrocytes. This phenotype is specific for cartilage precursors, since other neural crest-derived cell lineages, including glia, neurons and chromatophores, are formed normally in ring1b mutants. Our results therefore reveal a critical and specific role for Ring1b in promoting the differentiation of cranial neural crest cells into chondrocytes. The molecular mechanisms underlying the pathogenesis of craniofacial abnormalities, which are among the most common genetic birth defects in humans, remain poorly understood. The zebrafish ring1b mutant provides a molecular model for investigating these mechanisms and may lead to the discovery of new treatments or preventions of craniofacial abnormalities.
Collapse
|
40
|
Huang CJ, Wilson V, Pennings S, MacRae CA, Mullins J. Sequential effects of spadetail, one-eyed pinhead and no tail on midline convergence of nephric primordia during zebrafish embryogenesis. Dev Biol 2013; 384:290-300. [PMID: 23860396 DOI: 10.1016/j.ydbio.2013.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 06/12/2013] [Accepted: 07/05/2013] [Indexed: 12/16/2022]
Abstract
Midline convergence of organ primordia is an important mechanism that shapes the vertebrate body plan. Here, we focus on the morphogenetic movements of pronephric glomerular primordia (PGP) occurring during zebrafish embryonic kidney development. To characterize the process of PGP midline convergence, we used Wilms' tumour 1a (wt1a) as a marker to label kidney primordia, and performed quantitative analyses of the migration of the bilateral PGP. The PGP initially are approximately 350 μm apart in a wild type embryo at 10h post fertilization (hpf). The inter-PGP distance decreases exponentially between 10 and 48 hpf, while the anterior-posterior (A-P) dimension of each PGP increases linearly between 10 and 12 hpf, then decreases substantially between 12 and 24 hpf. Using mutants in the Nodal receptor cofactor one-eyed pinhead (oep) and the T-box transcription factors spadetail (spt) and no tail (ntl), we were able to define distinctive regulation underlying these sequential phases of PGP midline migration. Zygotic oep mutants (Zoep(-/-)) exhibited defects in midline convergence after 16 hpf. Spt is necessary for PGP convergence from 10 hpf, whereas ntl's effect on convergence does not begin until 24 hpf. Notably, we observed normal cardiac convergence in spt(-/-) and ntl(-/-) embryos implying that these novel roles of spt and ntl in PGP migration cannot be explained simply by generalised effects on midline convergence. These findings demonstrate that quantitative approaches to developmental migration allow the parsing of early patterning events, and in this instance suggest that the zebrafish may offer insights into midline urogenital migration anomalies in humans.
Collapse
|
41
|
Frohnhöfer HG, Krauss J, Maischein HM, Nüsslein-Volhard C. Iridophores and their interactions with other chromatophores are required for stripe formation in zebrafish. Development 2013; 140:2997-3007. [PMID: 23821036 PMCID: PMC3912879 DOI: 10.1242/dev.096719] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/10/2013] [Indexed: 11/21/2022]
Abstract
Colour patterns of adult fish are produced by several types of pigment cells that distribute in the dermis during juvenile development. The zebrafish, Danio rerio, displays a striking pattern of dark stripes of melanophores interspersed by light stripes of xanthophores. Mutants lacking either cell type do not form proper stripes, indicating that interactions between these two chromatophore types are required for stripe formation. A third cell type, silvery iridophores, participates to render a shiny appearance to the pattern, but its role in stripe formation has been unclear. Mutations in rose (rse) or shady (shd) cause a lack or strong reduction of iridophores in adult fish; in addition, the melanophore number is drastically reduced and stripes are broken up into spots. We show that rse and shd are autonomously required in iridophores, as mutant melanophores form normal sized stripes when confronted with wild-type iridophores in chimeric animals. We describe stripe formation in mutants missing one or two of the three chromatophore types. None of the chromatophore types alone is able to create a pattern but residual stripe formation occurs with two cell types. Our analysis shows that iridophores promote and sustain melanophores. Furthermore, iridophores attract xanthophores, whereas xanthophores repel melanophores. We present a model for the interactions between the three chromatophore types underlying stripe formation. Stripe formation is initiated by iridophores appearing at the horizontal myoseptum, which serves as a morphological landmark for stripe orientation, but is subsequently a self-organising process.
Collapse
Affiliation(s)
- Hans Georg Frohnhöfer
- Max-Planck-Institut für Entwicklungsbiologie, Spemannstr 35, 72076 Tübingen, Germany
| | - Jana Krauss
- Max-Planck-Institut für Entwicklungsbiologie, Spemannstr 35, 72076 Tübingen, Germany
| | - Hans-Martin Maischein
- Max-Planck-Institut für Entwicklungsbiologie, Spemannstr 35, 72076 Tübingen, Germany
| | | |
Collapse
|
42
|
Krauss J, Astrinidis P, Astrinides P, Frohnhöfer HG, Walderich B, Nüsslein-Volhard C. transparent, a gene affecting stripe formation in Zebrafish, encodes the mitochondrial protein Mpv17 that is required for iridophore survival. Biol Open 2013; 2:703-10. [PMID: 23862018 PMCID: PMC3711038 DOI: 10.1242/bio.20135132] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/07/2013] [Indexed: 11/20/2022] Open
Abstract
In the skin of adult zebrafish, three pigment cell types arrange into alternating horizontal stripes, melanophores in dark stripes, xanthophores in light interstripes and iridophores in both stripes and interstripes. The analysis of mutants and regeneration studies revealed that this pattern depends on interactions between melanophores and xanthophores; however, the role of iridophores in this process is less understood. We describe the adult viable and fertile mutant transparent (tra), which shows a loss or strong reduction of iridophores throughout larval and adult stages. In addition, in adults only the number of melanophores is strongly reduced, and stripes break up into spots. Stripes in the fins are normal. By cell transplantations we show that tra acts cell-autonomously in iridophores, whereas the reduction in melanophores in the body occurs secondarily as a consequence of iridophore loss. We conclude that differentiated iridophores are required for the accumulation and maintenance of melanophores during pigment pattern formation. The tra mutant phenotype is caused by a small deletion in mpv17, an ubiquituously expressed gene whose protein product, like its mammalian and yeast homologs, localizes to mitochondria. Iridophore death might be the result of mitochondrial dysfunction, consistent with the mitochondrial DNA depletion syndrome observed in mammalian mpv17 mutants. The specificity of the tra phenotype is most likely due to redundancy after gene multiplication, making this mutant a valuable model to understand the molecular function of Mpv17 in mitochondria.
Collapse
Affiliation(s)
- Jana Krauss
- Max-Planck-Institut für Entwicklungsbiologie , Spemannstrasse 35, 72076 Tübingen , Germany
| | | | | | | | | | | |
Collapse
|
43
|
Hsu CC, Pai WY, Lai CY, Lu MW, Her GM. Genetic characterization and in vivo image analysis of novel zebrafish Danio rerio pigment mutants. J Fish Biol 2013; 82:1671-1683. [PMID: 23639161 DOI: 10.1111/jfb.12109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Accepted: 02/19/2013] [Indexed: 06/02/2023]
Abstract
This study reports the isolation and characterization of a new type of transparent zebrafish Danio rerio mutant called pinky (pk), which has been visually isolated from a spontaneous mutation in a D. rerio colony. The pk larvae possess complex mutations affecting pigmentation because of missing pigment cells or a dramatic reduction in the chromatophore number. The pk displays a totally colourless phenotype and adult body transplant with no other obvious external morphological abnormalities, except for a red retina. The molecular analysis results in several candidate genes, hps1, ap3m2 and rabggta, implicated in the Hermansky-Pudlak syndrome (HPS) genes associated with HPS in pk. To demonstrate its applications of deep-tissue imaging, this study examines green fluorescent protein alone or with other fluorescent proteins to investigate their capability for using multilabelling purposes in live adult pk. In this study, pk is particularly valuable for tissue cell labelling and internal organogenesis studies because of its optical clarity in the adult body.
Collapse
Affiliation(s)
- C C Hsu
- Department of Radiology, Buddhist Tzu Chi General Hospital, Taichung Branch, No. 66, Sec. 1, Fongsing Rd, Tanzih Township, Taichung County 427, Taiwan
| | | | | | | | | |
Collapse
|
44
|
Feula A, Dhillon SS, Byravan R, Sangha M, Ebanks R, Hama Salih MA, Spencer N, Male L, Magyary I, Deng WP, Müller F, Fossey JS. Synthesis of azetidines and pyrrolidines via iodocyclisation of homoallyl amines and exploration of activity in a zebrafish embryo assay. Org Biomol Chem 2013; 11:5083-93. [DOI: 10.1039/c3ob41007b] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
45
|
Abstract
Teleosts are the largest and most diverse group of vertebrates, and many species undergo morphological, physiological, and behavioral transitions, "metamorphoses," as they progress between morphologically divergent life stages. The larval metamorphosis that generally occurs as teleosts mature from larva to juvenile involves the loss of embryo-specific features, the development of new adult features, major remodeling of different organ systems, and changes in physical proportions and overall phenotype. Yet, in contrast to anuran amphibians, for example, teleost metamorphosis can entail morphological change that is either sudden and profound, or relatively gradual and subtle. Here, we review the definition of metamorphosis in teleosts, the diversity of teleost metamorphic strategies and the transitions they involve, and what is known of their underlying endocrine and genetic bases. We suggest that teleost metamorphosis offers an outstanding opportunity for integrating our understanding of endocrine mechanisms, cellular processes of morphogenesis and differentiation, and the evolution of diverse morphologies and life histories.
Collapse
Affiliation(s)
- Sarah K. McMenamin
- Department of Biology, University of Washington, Seattle, Washington, USA
| | - David M. Parichy
- Department of Biology, University of Washington, Seattle, Washington, USA
| |
Collapse
|
46
|
O'Quin CT, Drilea AC, Roberts RB, Kocher TD. A small number of genes underlie male pigmentation traits in Lake Malawi cichlid fishes. J Exp Zool B Mol Dev Evol 2012; 318:199-208. [PMID: 22544717 DOI: 10.1002/jez.b.22006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Pigmentation patterns are one of the most recognizable forms of phenotypic diversity and an important component of organismal fitness. While much progress has been made in understanding the genes controlling pigmentation in model systems, many questions remain about the genetic basis of pigment traits observed in nature. Lake Malawi cichlid fishes are known for their diversity of male pigmentation patterns, which have been shaped by sexual selection. To begin the process of identifying the genes underlying this diversity, we quantified the number of pigment cells on the body and fins of two species of the genus Metriaclima and their hybrids. We then used the Castle-Wright equation to estimate that differences in individual pigmentation traits between these species are controlled by one to four genes each. Different pigmentation traits are highly correlated in the F(2) , suggesting shared developmental pathways and genetic pleiotropy. Melanophore and xanthophore traits fall on opposite ends of the first principal component axis of the F(2) phenotypes, suggesting a tradeoff during the development of these two pigment cell types.
Collapse
Affiliation(s)
- Claire T O'Quin
- Department of Biology, University of Maryland, College Park, Maryland, USA
| | | | | | | |
Collapse
|
47
|
Colanesi S, Taylor KL, Temperley ND, Lundegaard PR, Liu D, North TE, Ishizaki H, Kelsh RN, Patton EE. Small molecule screening identifies targetable zebrafish pigmentation pathways. Pigment Cell Melanoma Res 2012; 25:131-43. [PMID: 22252091 DOI: 10.1111/j.1755-148x.2012.00977.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [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: 01/18/2023]
Abstract
Small molecules complement genetic mutants and can be used to probe pigment cell biology by inhibiting specific proteins or pathways. Here, we present the results of a screen of active compounds for those that affect the processes of melanocyte and iridophore development in zebrafish and investigate the effects of a few of these compounds in further detail. We identified and confirmed 57 compounds that altered pigment cell patterning, number, survival, or differentiation. Additional tissue targets and toxicity of small molecules are also discussed. Given that the majority of cell types, including pigment cells, are conserved between zebrafish and other vertebrates, we present these chemicals as molecular tools to study developmental processes of pigment cells in living animals and emphasize the value of zebrafish as an in vivo system for testing the on- and off-target activities of clinically active drugs.
Collapse
Affiliation(s)
- Sarah Colanesi
- Developmental Biology Programme, Centre for Regenerative Medicine, Department of Biology and Biochemistry, University of Bath, Bath, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Van den Bulck K, Hill A, Mesens N, Diekman H, De Schaepdrijver L, Lammens L. Zebrafish developmental toxicity assay: A fishy solution to reproductive toxicity screening, or just a red herring? Reprod Toxicol 2011; 32:213-9. [DOI: 10.1016/j.reprotox.2011.06.119] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 06/02/2011] [Accepted: 06/14/2011] [Indexed: 10/18/2022]
|
49
|
Gunter HM, Clabaut C, Salzburger W, Meyer A. Identification and characterization of gene expression involved in the coloration of cichlid fish using microarray and qRT-PCR approaches. J Mol Evol 2011; 72:127-37. [PMID: 21267555 DOI: 10.1007/s00239-011-9431-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 01/03/2011] [Indexed: 01/09/2023]
Abstract
It has been suggested that speciation on the basis of sexual selection is an important mechanism for the generation of new species for East African cichlids, where male body coloration is one of the major discriminatory factors used by females in mate choice. To gain insight into the molecular basis of cichlid coloration, we studied the Lake Malawi cichlid Pseudotropheus saulosi, comparing transcription in the bright blue skin of males to the yellow skin of females. Our cDNA microarray experiments identified 46 clones that exhibited expression differences between the two sexes, of which five were confirmed to be differentially expressed by relative quantitative real-time PCR (qRT-PCR). This gene list includes a representative from the endosomal-to-Golgi vesicle trafficking pathway, Coatomer protein complex, subunit zeta-1 (Copz-1), which is known to be a critical determinant of pigmentation in humans and zebrafish. With the support of microscopic images of the skin of these specimens, we interpret the transcriptional differences between the blue males and yellow females. Here, we provide insight into the putative functional diversification of genes involved in the coloration of cichlids and by extension, on the evolution of coloration in teleost fish.
Collapse
Affiliation(s)
- Helen M Gunter
- Lehrstuhl für Zoologie und Evolutionsbiologie, Department of Biology, University of Konstanz, Universitätsstr 10, 78457 Constance, Germany
| | | | | | | |
Collapse
|
50
|
Po MD, Hwang C, Zhen M. PHRs: bridging axon guidance, outgrowth and synapse development. Curr Opin Neurobiol 2010; 20:100-7. [PMID: 20079626 DOI: 10.1016/j.conb.2009.12.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 12/19/2009] [Accepted: 12/22/2009] [Indexed: 10/20/2022]
Abstract
Axon guidance, outgrowth, and synapse formation are interrelated developmental events during the maturation of the nervous system. Establishing proper synaptic connectivity requires precise axon navigation and a coordinated switch between axon outgrowth and synaptogenesis. The PHR (human Pam, mouse Phr1, zebrafish Esrom, DrosophilaHighwire, and C. elegansRPM-1) protein family regulates both axon and synapse development through their biochemical and functional interactions with multiple signaling pathways. Recent studies have begun to elucidate a common underlying mechanism for PHR functions: Consisting of motifs that affect intracellular signaling, selective protein degradation, and cytoskeleton organization, PHR proteins probably mediate the transition between axon outgrowth and synaptogenesis through integrating intracellular signaling and microtubule remodeling.
Collapse
Affiliation(s)
- Michelle D Po
- Department of Molecular Genetics, University of Toronto, Canada; Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Canada
| | | | | |
Collapse
|