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FASEB Journal : Official Publication of... Dec 1999
Review
Topics: Animals; Melanophores; Microtubules
PubMed: 10619131
DOI: 10.1096/fasebj.13.9002.s221 -
Development, Growth & Differentiation Sep 2018In zebrafish, apart from mononuclear melanophores, bi- and trinuclear melanophores are frequently observed; however, the manner in which multinucleation of these cells...
In zebrafish, apart from mononuclear melanophores, bi- and trinuclear melanophores are frequently observed; however, the manner in which multinucleation of these cells occurs during fish development remains unknown. Here, we analyzed the processes underlying multinucleation of zebrafish melanophores. Transgenic zebrafish in which melanophore nuclei were labeled with a histone H2B-red fluorescent reporter protein were used to evaluate the distribution of mono-, bi-, and trinuclear melanophores in both the trunk and fin. Half of the melanophores examined were binuclear and approximately 1% were trinuclear. We compared cell size, cell motility, and survival rate between mono- and binuclear melanophores grown in a culture dish, and we found that cell size and survival rate were significantly larger in binuclear melanophores. We then analyzed the behavior of melanoblasts and melanophores from transgenic zebrafish using in vivo and in vitro live-cell imaging. We detected division and differentiation of melanoblasts, as well as melanoblast nuclear division without subsequent cellular division. In addition, we observed cellular and nuclear division in melanophores, although these events were very infrequent in vitro. On the basis of our findings, we present a scheme for melanophore multinucleation in zebrafish.
Topics: Animals; Cells, Cultured; Melanophores; Zebrafish
PubMed: 30088265
DOI: 10.1111/dgd.12564 -
Microscopy Research and Technique Sep 2002Melanophore melanosomes organelles can be regulated to move and locate correspondingly to many other different organelle types. Comparing lessons from analysis of a... (Review)
Review
Melanophore melanosomes organelles can be regulated to move and locate correspondingly to many other different organelle types. Comparing lessons from analysis of a specific melanosome distribution can, therefore, contribute to the understanding of distribution of other organelles, and vice versa. From such data, it is now generally accepted that microtubules provide directed long-distance movement, while cell peripheral movements include microfilaments. In fish melanophores, both actin and dynein exhibit counter-forces to the kinesin-like protein in maintaining the evenly dispersed state, while actin and kinesin exhibit counter-forces to dynein in many other systems. Lessons from elevating cAMP levels indicate the presence of a peripheral feedback regulatory system involved in maintaining the evenly dispersed state. Studies from dynein inhibition suggest that the kinesin-like protein involved in fish melanosome dispersal is regulated in contrast to many other systems. One would further expect melanosome transport to be regulated also on actin/myosin, in order to prevent actin-dependent capture of melanosomes during the microtubule-dependent aggregation and dispersion. General findings will be discussed in comparison with positioning and movement of other organelle types in cells. Finally, recent data on melanosome-dependent organising of microtubules show that dynein is involved in nucleating microtubules extending from melanosome aggregates in melanophore fragments.
Topics: Animals; Biological Transport; Cytoskeleton; Fishes; Melanophores; Melanosomes; Microscopy, Electron
PubMed: 12242703
DOI: 10.1002/jemt.10164 -
Developmental Biology Aug 2009We describe a mechanistic model whereby Foxd3, a forkhead transcription factor, prevents neural crest-derived precursors from acquiring a melanophore fate. Foxd3...
We describe a mechanistic model whereby Foxd3, a forkhead transcription factor, prevents neural crest-derived precursors from acquiring a melanophore fate. Foxd3 regulates this fate choice by repressing the mitfa promoter in a subset of neural crest cells. mitfa is only expressed in a Foxd3-negative subset of neural crest cells, and foxd3 mutants show an increase in the spatial domain of mitfa expression, thereby suggesting that Foxd3 limits the mitfa domain. Furthermore, foxd3:gfp transgenic zebrafish reveal foxd3 expression in xanthophore precursors and iridophores, but not in terminally differentiated melanophores. Luciferase experiments and embryo mRNA injections indicate Foxd3 acts directly on the mitfa promoter to negatively regulate mitfa expression. Taken together, our data suggests the presence of Foxd3 in a subset of precursors leads to mitfa repression and suppression of melanophore fate. MITF, the human mitfa ortholog, has recently been described as an oncogene and implicated in various forms of melanoma. Understanding the mechanisms that regulate mitfa and melanophore development could prove informative in the treatment and prevention of these human diseases.
Topics: Animals; Animals, Genetically Modified; Cells, Cultured; Forkhead Transcription Factors; Gene Expression Regulation, Developmental; Humans; Melanophores; Mice; Microphthalmia-Associated Transcription Factor; NIH 3T3 Cells; Neural Crest; Promoter Regions, Genetic; Recombinant Fusion Proteins; Zebrafish; Zebrafish Proteins
PubMed: 19527705
DOI: 10.1016/j.ydbio.2009.06.010 -
Pigment Cell Research Feb 2002Red tilapia has aroused interest in many countries for its commercial potential. This tilapia strain combines a desirable coloration and appearance with other...
Red tilapia has aroused interest in many countries for its commercial potential. This tilapia strain combines a desirable coloration and appearance with other advantageous farming characteristics. To study the early appearance of melanophore pigmentation in tilapia, a red tilapia strain originating from Thailand and a wild type coloration of Oreochromis niloticus were used as broodstock to produce artificially wild x wild and red x red progenies. The larvae were assessed periodically up to the first feeding and were recorded. Wild type fish showed a regular appearance of stellate melanophores. In the red strain, the pattern of chromatophores varies from total absence of black spotting to different degrees of macromelanophore distribution. Comparison between red and wild types showed that these two tilapia can be easily scored at day 7. Further, we present indications that the pigmentation over the body develops independently of the initial degree of pigmentation.
Topics: Animals; Female; Male; Melanophores; Pigmentation; Tilapia
PubMed: 11837457
DOI: 10.1034/j.1600-0749.2002.00058.x -
Scientific Reports Jan 2023With disease progression, individual differences appear, even in an animal disease model with genetic homogeneity. Therefore, non-invasive long term observation and...
With disease progression, individual differences appear, even in an animal disease model with genetic homogeneity. Therefore, non-invasive long term observation and individual identification is desirable for late-onset diseases. To this end, the natural markings used in ecological studies are preferable to the external invasive markings used in animal husbandry and fisheries management. Here, we propose using the distribution pattern of melanophore spots on the head of an inbred strain of medaka, a small fish model organism with monotonous pigmentation, as biometric identifier. Long term and variation analyses show different patterns whose characteristics can be attributed to individual animals. These findings were also valid in a non-inbred medaka strain and will help individual follow-up of late-onset disease medaka models for the elucidation of the pathogenesis and drug discovery.
Topics: Animals; Oryzias; Pigmentation; Melanophores
PubMed: 36635463
DOI: 10.1038/s41598-023-27386-w -
Frontiers in Endocrinology 2022Koi carp, an ornamental fish derived from the common carp (CC), is characterized by beautiful skin color patterns. However, the mechanism that gives rise to the...
INTRODUCTION
Koi carp, an ornamental fish derived from the common carp (CC), is characterized by beautiful skin color patterns. However, the mechanism that gives rise to the characteristic vivid skin coloration of koi carp has not been clarified. The skin coloration of many teleosts changes in response to differences in the background color. This change in skin coloration is caused by diffusion or aggregation of pigment granules in chromatophores and is regulated mainly by sympathetic nerves and hormones. We hypothesized that there would be some abnormality in the mechanism of skin color regulation in koi carp, which impairs skin color fading in response to background color.
METHODS
We compared the function of melanin-concentrating hormone (MCH), noradrenaline, and adrenaline in CC and (TS), a variety of tri-colored koi.
RESULTS AND DISCUSSION
In CC acclimated to a white background, the skin color became paler and pigment granules aggregated in melanophores in the scales compared to that in black-acclimated CC. There were no clear differences in skin color or pigment granule aggregation in white- or black-acclimated TS. The expression of mRNA in the brain was higher in the white-acclimated CC than that in the black-acclimated CC. However, the expression of mRNA in the brain in the TS did not change in response to the background color. Additionally, plasma MCH levels did not differ between white- and black-acclimated fish in either CC or TS. experiments showed that noradrenaline induced pigment aggregation in scale melanophores in both CC and TS, whereas adrenaline induced pigment aggregation in the CC but not in the TS. administration of MCH induced pigment granule aggregation in the CC but not in the TS. However, intraperitoneal injection of MCH resulted in pigment granule aggregation in both CC and TS. Collectively, these results suggest that the weak sensitivity of scale melanophores to MCH and adrenaline might be responsible for the lack of skin color change in response to background color in the TS.
Topics: Animals; Epinephrine; Carps; Melanophores; Norepinephrine; RNA, Messenger
PubMed: 36619537
DOI: 10.3389/fendo.2022.994060 -
PLoS Genetics 2012The zebrafish adult pigment pattern has emerged as a useful model for understanding the development and evolution of adult form as well as pattern-forming mechanisms...
The zebrafish adult pigment pattern has emerged as a useful model for understanding the development and evolution of adult form as well as pattern-forming mechanisms more generally. In this species, a series of horizontal melanophore stripes arises during the larval-to-adult transformation, but the genetic and cellular bases for stripe formation remain largely unknown. Here, we show that the seurat mutant phenotype, consisting of an irregular spotted pattern, arises from lesions in the gene encoding Immunoglobulin superfamily member 11 (Igsf11). We find that Igsf11 is expressed by melanophores and their precursors, and we demonstrate by cell transplantation and genetic rescue that igsf11 functions autonomously to this lineage in promoting adult stripe development. Further analyses of cell behaviors in vitro, in vivo, and in explant cultures ex vivo demonstrate that Igsf11 mediates adhesive interactions and that mutants for igsf11 exhibit defects in both the migration and survival of melanophores and their precursors. These findings identify the first in vivo requirements for igsf11 as well as the first instance of an immunoglobulin superfamily member functioning in pigment cell development and patterning. Our results provide new insights into adult pigment pattern morphogenesis and how cellular interactions mediate pattern formation.
Topics: Animals; Biological Evolution; Body Patterning; Cell Adhesion Molecules; Cell Differentiation; Cell Movement; Cell Survival; Embryo, Nonmammalian; Fish Proteins; Gene Expression Regulation, Developmental; Immunoglobulins; Larva; Melanophores; Mutation; Phenotype; Pigmentation; Zebrafish; Zebrafish Proteins
PubMed: 22916035
DOI: 10.1371/journal.pgen.1002899 -
PloS One 2013Here, we characterize a Danio rerio zebrafish pigment cell mutant (melanophore integrity mutant), which displays a defect in maintenance of melanophore and iridophore...
Here, we characterize a Danio rerio zebrafish pigment cell mutant (melanophore integrity mutant), which displays a defect in maintenance of melanophore and iridophore number. Mapping and candidate gene analysis links the melanophore integrity mutant mutation to the vacuolar protein sorting 11 (vps11(w66)) gene. Quantification of vps11(w66) chromatophores during larval stages suggests a decrease in number as compared to wildtype siblings. TUNEL analysis and treatment with the caspase inhibitor, zVAD-fmk, indicate that vps11(w66) chromatophore death is caspase independent. Western blot analysis of PARP-1 cleavage patterns in mutant lysates suggests that increases in pH dependent cathepsin activity is involved in the premature chromatophore death observed in vps11(w66) mutants. Consistently, treatment with ALLM and Bafilomycin A1 (cathepsin/calpain and vacuolar-type H+-ATPase inhibitors, respectively), restore normal melanophore morphology and number in vps11(w66) mutants. Last, LC3B western blot analysis indicates an increase in autophagosome marker, LC3B II in vps11(w66) mutants as compared to wildtype control, but not in ALLM or Bafilomycin A1 treated mutants. Taken together, these data suggest that vps11 promotes normal melanophore morphology and survival by inhibiting cathepsin release and/or activity.
Topics: Animals; Autophagy; Caspases; Cathepsins; Cell Survival; Chromosome Mapping; Chromosomes; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation; Macrolides; Melanophores; Mutation; Organ Specificity; Vesicular Transport Proteins; Zebrafish; Zebrafish Proteins
PubMed: 23724125
DOI: 10.1371/journal.pone.0065096 -
Current Protocols in Pharmacology Jul 2005The melanophore bioassay is a robust, sensitive, and versatile procedure for screening G protein-coupled receptors in a variety of formats. Because melanophores contain...
The melanophore bioassay is a robust, sensitive, and versatile procedure for screening G protein-coupled receptors in a variety of formats. Because melanophores contain a wide variety of G proteins, they can be employed as a sensitive, real-time response system for studying transfected receptors and for defining equilibria for drug effects. This assay can be run in 96-well microtiter plates or in open-lawn 1536 format, and can yield conventional agonist-antagonist as well as constitutive assays.
Topics: Animals; Cell Line; Drug Evaluation, Preclinical; Melanophores; Receptors, G-Protein-Coupled; Xenopus laevis
PubMed: 21953388
DOI: 10.1002/0471141755.ph1209s29