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Perlee S, Ma Y, Hunter MV, Swanson JB, Ming Z, Xia J, Lionnet T, McGrail M, White RM. Identifying in vivo genetic dependencies of melanocyte and melanoma development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.22.586101. [PMID: 38562693 PMCID: PMC10983904 DOI: 10.1101/2024.03.22.586101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The advent of large-scale sequencing in both development and disease has identified large numbers of candidate genes that may be linked to important phenotypes. Validating the function of these candidates in vivo is challenging, due to low efficiency and low throughput of most model systems. We have developed a rapid, scalable system for assessing the role of candidate genes using zebrafish. We generated transgenic zebrafish in which Cas9 was knocked-in to the endogenous mitfa locus, a master transcription factor of the melanocyte lineage. We used this system to identify both cell-autonomous and non-cell autonomous regulators of normal melanocyte development. We then applied this to the melanoma setting to demonstrate that loss of genes required for melanocyte survival can paradoxically promote more aggressive phenotypes, highlighting that in vitro screens can mask in vivo phenotypes. Our high-efficiency genetic approach offers a versatile tool for exploring developmental processes and disease mechanisms that can readily be applied to other cell lineages.
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Kang DY, Kim HC. Functional relation of agouti signaling proteins (ASIPs) to pigmentation and color change in the starry flounder, Platichthys stellatus. Comp Biochem Physiol A Mol Integr Physiol 2024; 291:111524. [PMID: 37981006 DOI: 10.1016/j.cbpa.2023.111524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/30/2023] [Accepted: 10/01/2023] [Indexed: 11/21/2023]
Abstract
We investigated the involvement of agouti-signaling proteins (ASIPs) in morphological pigmentation and physiological color change in flatfishes. We isolated ASIP1 and 2 mRNAs from the skin of starry flounder (Platichthys stellatus), and compared their amino acid (aa) structures to those of other animals. Then, we examined the mRNA expression levels of two ASIPs (Sf-ASIPs) in the pigmented ocular body and in the unpigmented blind body, as well as in the ordinary skin and in albino skin, in flatfishes. To investigate the role of Sf-ASIPs in physiological color change (color camouflage), we compared the expression of the two genes in two background colors (dark-green and white). Sf-ASIP1 cDNA had a 375-bp open reading frame (ORF) that encoded a protein consisting of 125 aa residues, and Sf-ASIP2 cDNA had a 402-bp ORF that encoded a protein consisting of 132 aa residues. RT-PCR revealed that the strongest Sf-ASIP1 and Sf-ASIP2 expression levels were observed in the eye and blind-skin, respectively. In Sf-ASIP1, the gene expression did not differ between the ocular-side skin and blind-side skin, nor between ordinary skin and abnormal skin of the fish. However, in Sf-ASIP2, the expression level was significantly higher in blind-side skin, compared to ocular-side skin, suggesting that the ASIP2 gene is related to the countershading body pigment pattern of the fish. In addition, the Sf-ASIP2 gene expression level was lower in the pigmented spot regions than in the unpigmented spot regions of the malpigmented pseudo-albino skins on the ocular side, implying that ASIP2 is responsible for the ocular-side pseudo-albino. Additionally, ASIP2 gene expression in the blind-side skin of ordinary fish was enhanced by a white tank, implying that a bright background color could inhibit hypermelanosis in the blind-side skin of cultured flounder by increasing the activity of the Sf-ASIP2 gene. However, we did not find any relationship of ASIPs with camouflage color changes. In conclusion, the ASIP2 gene is related to the morphological pigmentation (countershading and malpigmentation) of the skin in starry flounder, but not with physiological color changes (color camouflage) in the ocular-side skin.
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Affiliation(s)
- Duk-Young Kang
- National Institute of Fisheries Science, West Sea Fisheries Research Institute, 707 Eulwang-dong, Jung-gu, Incheon, Republic of Korea.
| | - Hyo-Chan Kim
- KMS & MC, Molecular research, Haneulbyeolbit-ro, YoungJong-1 dong, Joong-gu, Incheon, Republic of Korea
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3
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Beaulieu MO, Thomas ED, Raible DW. Transdifferentiation is uncoupled from progenitor pool expansion during hair cell regeneration in the zebrafish inner ear. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.09.588777. [PMID: 38645220 PMCID: PMC11030336 DOI: 10.1101/2024.04.09.588777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Death of mechanosensory hair cells in the inner ear is a common cause of auditory and vestibular impairment in mammals, which have a limited ability to regrow these cells after damage. In contrast, non-mammalian vertebrates including zebrafish can robustly regenerate hair cells following severe organ damage. The zebrafish inner ear provides an understudied model system for understanding hair cell regeneration in organs that are highly conserved with their mammalian counterparts. Here we quantitatively examine hair cell addition during growth and regeneration of the larval zebrafish inner ear. We used a genetically encoded ablation method to induce hair cell death and observed gradual regeneration with correct spatial patterning over two weeks following ablation. Supporting cells, which surround and are a source of new hair cells, divide in response to hair cell ablation, expanding the possible progenitor pool. In parallel, nascent hair cells arise from direct transdifferentiation of progenitor pool cells uncoupled from progenitor division. These findings reveal a previously unrecognized mechanism of hair cell regeneration with implications for how hair cells may be encouraged to regenerate in the mammalian ear.
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Affiliation(s)
- Marielle O. Beaulieu
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
| | - Eric D. Thomas
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
| | - David W. Raible
- Molecular and Cellular Biology Graduate Program, Seattle, WA
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology - Head and Neck Surgery, Seattle, WA
- Neuroscience Graduate Program, Seattle, WA
- Department of Biological Structure University of Washington, Seattle, WA
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4
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Wu CLS, Cioanca AV, Gelmi MC, Wen L, Di Girolamo N, Zhu L, Natoli R, Conway RM, Petsoglou C, Jager MJ, McCluskey PJ, Madigan MC. The multifunctional human ocular melanocortin system. Prog Retin Eye Res 2023; 95:101187. [PMID: 37217094 DOI: 10.1016/j.preteyeres.2023.101187] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 05/24/2023]
Abstract
Immune privilege in the eye involves physical barriers, immune regulation and secreted proteins that together limit the damaging effects of intraocular immune responses and inflammation. The neuropeptide alpha-melanocyte stimulating hormone (α-MSH) normally circulates in the aqueous humour of the anterior chamber and the vitreous fluid, secreted by iris and ciliary epithelium, and retinal pigment epithelium (RPE). α-MSH plays an important role in maintaining ocular immune privilege by helping the development of suppressor immune cells and by activating regulatory T-cells. α-MSH functions by binding to and activating melanocortin receptors (MC1R to MC5R) and receptor accessory proteins (MRAPs) that work in concert with antagonists, otherwise known as the melanocortin system. As well as controlling immune responses and inflammation, a broad range of biological functions is increasingly recognised to be orchestrated by the melanocortin system within ocular tissues. This includes maintaining corneal transparency and immune privilege by limiting corneal (lymph)angiogenesis, sustaining corneal epithelial integrity, protecting corneal endothelium and potentially enhancing corneal graft survival, regulating aqueous tear secretion with implications for dry eye disease, facilitating retinal homeostasis via maintaining blood-retinal barriers, providing neuroprotection in the retina, and controlling abnormal new vessel growth in the choroid and retina. The role of melanocortin signalling in uveal melanocyte melanogenesis however remains unclear compared to its established role in skin melanogenesis. The early application of a melanocortin agonist to downregulate systemic inflammation used adrenocorticotropic hormone (ACTH)-based repository cortisone injection (RCI), but adverse side effects including hypertension, edema, and weight gain, related to increased adrenal gland corticosteroid production, impacted clinical uptake. Compared to ACTH, melanocortin peptides that target MC1R, MC3R, MC4R and/or MC5R, but not adrenal gland MC2R, induce minimal corticosteroid production with fewer amdverse systemic effects. Pharmacological advances in synthesising MCR-specific targeted peptides provide further opportunities for treating ocular (and systemic) inflammatory diseases. Following from these observations and a renewed clinical and pharmacological interest in the diverse biological roles of the melanocortin system, this review highlights the physiological and disease-related involvement of this system within human eye tissues. We also review the emerging benefits and versatility of melanocortin receptor targeted peptides as non-steroidal alternatives for inflammatory eye diseases such as non-infectious uveitis and dry eye disease, and translational applications in promoting ocular homeostasis, for example, in corneal transplantation and diabetic retinopathy.
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Affiliation(s)
- Chieh-Lin Stanley Wu
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, Australia; Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; Department of Optometry, Asia University, Taichung, Taiwan
| | - Adrian V Cioanca
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; John Curtin School of Medical Research, The Australian National University, ACT, Australia; ANU Medical School, The Australian National University, ACT, Australia
| | - Maria C Gelmi
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Li Wen
- New South Wales Organ and Tissue Donation Service, Sydney Hospital and Sydney Eye Hospital, NSW, 2000, Australia
| | - Nick Di Girolamo
- School of Biomedical Sciences, Mechanisms of Disease and Translational Research, University of New South Wales, Sydney, Australia
| | - Ling Zhu
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Riccardo Natoli
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; John Curtin School of Medical Research, The Australian National University, ACT, Australia; ANU Medical School, The Australian National University, ACT, Australia
| | - R Max Conway
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Constantinos Petsoglou
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; New South Wales Organ and Tissue Donation Service, Sydney Hospital and Sydney Eye Hospital, NSW, 2000, Australia
| | - Martine J Jager
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Peter J McCluskey
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Michele C Madigan
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, Australia; Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.
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5
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Sox2 in the dermal papilla regulates hair follicle pigmentation. Cell Rep 2022; 40:111100. [PMID: 35858560 DOI: 10.1016/j.celrep.2022.111100] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 04/15/2022] [Accepted: 06/23/2022] [Indexed: 12/18/2022] Open
Abstract
Within the hair follicle (HF) niche, dermal papilla (DP) cells are well known for the hair induction capacity; however, DP cell signaling also regulates HF pigmentation. Here we describe how Sox2 in the DP is a key regulator of melanocyte signaling. To study the largely unknown regulatory role the DP has on hair pigmentation, we characterize leptin receptor (Lepr) expression in the skin and as a genetic tool to target the DP. Sox2 ablation in the DP results in a phenotypic switch from eumelanin to pheomelanin. Mechanistically, we describe a temporal upregulation of Agouti and downregulation of Corin, directly by Sox2 in the DP. We also show that bone morphogenic protein (BMP) signaling regulation by Sox2 is responsible for downregulating MC1R, Dct, and Tyr in melanocytes of Sox2 cKO mice. Thus, we demonstrate that Sox2 in the DP regulates not only the choice of hair pigment but also the overall HF pigment production.
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Manganelli M, Guida S, Ferretta A, Pellacani G, Porcelli L, Azzariti A, Guida G. Behind the Scene: Exploiting MC1R in Skin Cancer Risk and Prevention. Genes (Basel) 2021; 12:1093. [PMID: 34356109 PMCID: PMC8305013 DOI: 10.3390/genes12071093] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/14/2021] [Accepted: 07/16/2021] [Indexed: 02/06/2023] Open
Abstract
Melanoma and non-melanoma skin cancers (NMSCs) are the most frequent cancers of the skin in white populations. An increased risk in the development of skin cancers has been associated with the combination of several environmental factors (i.e., ultraviolet exposure) and genetic background, including melanocortin-1 receptor (MC1R) status. In the last few years, advances in the diagnosis of skin cancers provided a great impact on clinical practice. Despite these advances, NMSCs are still the most common malignancy in humans and melanoma still shows a rising incidence and a poor prognosis when diagnosed at an advanced stage. Efforts are required to underlie the genetic and clinical heterogeneity of melanoma and NMSCs, leading to an optimization of the management of affected patients. The clinical implications of the impact of germline MC1R variants in melanoma and NMSCs' risk, together with the additional risk conferred by somatic mutations in other peculiar genes, as well as the role of MC1R screening in skin cancers' prevention will be addressed in the current review.
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Affiliation(s)
- Michele Manganelli
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
- DMMT-Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Stefania Guida
- Department of Surgical-Medical-Dental and Morphological Science with Interest Transplant-Oncological and Regenerative Medicine, University of Modena and Reggio Emilia, 41124 Modena, Italy;
| | - Anna Ferretta
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
| | - Giovanni Pellacani
- Department of Clinical Internal, Anesthesiological and Cardiovascular Sciences, Dermatology Clinic, Sapienza University of Rome, 00161 Rome, Italy;
| | - Letizia Porcelli
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori Giovanni Paolo II, 70124 Bari, Italy; (L.P.); (A.A.)
| | - Amalia Azzariti
- Laboratory of Experimental Pharmacology, IRCCS Istituto Tumori Giovanni Paolo II, 70124 Bari, Italy; (L.P.); (A.A.)
| | - Gabriella Guida
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari-“Aldo Moro”, 70125 Bari, Italy; (M.M.); (A.F.)
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Abstract
Metastasis, the dispersal of cancer cells from a primary tumor to secondary sites within the body, is the leading cause of cancer-related death. Animal models have been an indispensable tool to investigate the complex interactions between the cancer cells and the tumor microenvironment during the metastatic cascade. The zebrafish (Danio rerio) has emerged as a powerful vertebrate model for studying metastatic events in vivo. The zebrafish has many attributes including ex-utero development, which facilitates embryonic manipulation, as well as optically transparent tissues, which enables in vivo imaging of fluorescently labeled cells in real time. Here, we summarize the techniques which have been used to study cancer biology and metastasis in the zebrafish model organism, including genetic manipulation and transgenesis, cell transplantation, live imaging, and high-throughput compound screening. Finally, we discuss studies using the zebrafish, which have complemented and benefited metastasis research.
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Affiliation(s)
- Katy R Astell
- The Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
| | - Dirk Sieger
- The Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
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8
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Bruders R, Van Hollebeke H, Osborne EJ, Kronenberg Z, Maclary E, Yandell M, Shapiro MD. A copy number variant is associated with a spectrum of pigmentation patterns in the rock pigeon (Columba livia). PLoS Genet 2020; 16:e1008274. [PMID: 32433666 PMCID: PMC7239393 DOI: 10.1371/journal.pgen.1008274] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 04/09/2020] [Indexed: 12/15/2022] Open
Abstract
Rock pigeons (Columba livia) display an extraordinary array of pigment pattern variation. One such pattern, Almond, is characterized by a variegated patchwork of plumage colors that are distributed in an apparently random manner. Almond is a sex-linked, semi-dominant trait controlled by the classical Stipper (St) locus. Heterozygous males (ZStZ+ sex chromosomes) and hemizygous Almond females (ZStW) are favored by breeders for their attractive plumage. In contrast, homozygous Almond males (ZStZSt) develop severe eye defects and often lack plumage pigmentation, suggesting that higher dosage of the mutant allele is deleterious. To determine the molecular basis of Almond, we compared the genomes of Almond pigeons to non-Almond pigeons and identified a candidate St locus on the Z chromosome. We found a copy number variant (CNV) within the differentiated region that captures complete or partial coding sequences of four genes, including the melanosome maturation gene Mlana. We did not find fixed coding changes in genes within the CNV, but all genes are misexpressed in regenerating feather bud collar cells of Almond birds. Notably, six other alleles at the St locus are associated with depigmentation phenotypes, and all exhibit expansion of the same CNV. Structural variation at St is linked to diversity in plumage pigmentation and gene expression, and thus provides a potential mode of rapid phenotypic evolution in pigeons. The genetic changes responsible for different animal color patterns are poorly understood, due in part to a paucity of research organisms that are both genetically tractable and phenotypically diverse. Domestic pigeons (Columba livia) have been artificially selected for many traits, including an enormous variety of color patterns that are variable both within and among different breeds of this single species. We investigated the genetic basis of a sex-linked color pattern in pigeons called Almond that is characterized by a sprinkled pattern of plumage pigmentation. Pigeons with one copy of the Almond allele have desirable color pattern; however, male pigeons with two copies of the Almond mutation have severely depleted pigmentation and congenital eye defects. By comparing the genomes of Almond and non-Almond pigeons, we discovered that Almond pigeons have extra copies of a chromosome region that contains a gene that is critical for the formation of pigment granules. We also found that different numbers of copies of this region are associated with varying degrees of pigment reduction. The Almond phenotype in pigeons bears a remarkable resemblance to Merle coat color mutants in dogs, and our new results from pigeons suggest that similar genetic mechanisms underlie these traits in both species. Our work highlights the role of gene copy number variation as a potential driver of rapid phenotypic evolution.
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Affiliation(s)
- Rebecca Bruders
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Hannah Van Hollebeke
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Edward J. Osborne
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, United States of America
| | - Zev Kronenberg
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, United States of America
| | - Emily Maclary
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
| | - Mark Yandell
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, United States of America
| | - Michael D. Shapiro
- School of Biological Sciences, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
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9
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Morenikeji OB, Ajayi OO, Peters SO, Mujibi FD, De Donato M, Thomas BN, Imumorin IG. RNA-seq profiling of skin in temperate and tropical cattle. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2020; 62:141-158. [PMID: 32292922 PMCID: PMC7142279 DOI: 10.5187/jast.2020.62.2.141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 12/09/2019] [Accepted: 01/03/2020] [Indexed: 11/20/2022]
Abstract
Skin is a major thermoregulatory organ in the body controlling homeothermy, a critical function for climate adaptation. We compared genes expressed between tropical- and temperate-adapted cattle to better understand genes involved in climate adaptation and hence thermoregulation. We profiled the skin of representative tropical and temperate cattle using RNA-seq. A total of 214,754,759 reads were generated and assembled into 72,993,478 reads and were mapped to unique regions in the bovine genome. Gene coverage of unique regions of the reference genome showed that of 24,616 genes, only 13,130 genes (53.34%) displayed more than one count per million reads for at least two libraries and were considered suitable for downstream analyses. Our results revealed that of 255 genes expressed differentially, 98 genes were upregulated in tropically-adapted White Fulani (WF; Bos indicus) and 157 genes were down regulated in WF compared to Angus, AG (Bos taurus). Fifteen pathways were identified from the differential gene sets through gene ontology and pathway analyses. These include the significantly enriched melanin metabolic process, proteinaceous extracellular matrix, inflammatory response, defense response, calcium ion binding and response to wounding. Quantitative PCR was used to validate six representative genes which are associated with skin thermoregulation and epithelia dysfunction (mean correlation 0.92; p < 0.001). Our results contribute to identifying genes and understanding molecular mechanisms of skin thermoregulation that may influence strategic genomic selection in cattle to withstand climate adaptation, microbial invasion and mechanical damage.
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Affiliation(s)
- Olanrewaju B Morenikeji
- Department of Animal Production and Health, Federal University of Technology, Akure, Nigeria.,Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY, USA.,Animal Genetics and Genomics Laboratory, Office of International Programs, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Oyeyemi O Ajayi
- Animal Genetics and Genomics Laboratory, Office of International Programs, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853, USA.,Department of Animal Breeding and Genetics, Federal University of Agriculture, Abeokuta, Nigeria
| | - Sunday O Peters
- Department of Animal Science, Berry College, Mount Berry, GA 30149, USA
| | | | - Marcos De Donato
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Queretaro 76130, Mexico
| | - Bolaji N Thomas
- Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY, USA
| | - Ikhide G Imumorin
- Animal Genetics and Genomics Laboratory, Office of International Programs, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853, USA.,African Institute of Bioscience Research and Training, Ibadan, Nigeria.,Department of Biological Sciences, First Technical University, Ibadan, Nigeria.,School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
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10
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Cal L, Suarez‐Bregua P, Braasch I, Irion U, Kelsh R, Cerdá‐Reverter JM, Rotllant J. Loss‐of‐function mutations in the melanocortin 1 receptor cause disruption of dorso‐ventral countershading in teleost fish. Pigment Cell Melanoma Res 2019; 32:817-828. [DOI: 10.1111/pcmr.12806] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/24/2019] [Accepted: 06/25/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Laura Cal
- Department of Biotechnology & Aquaculture, FishBioTech Lab. Institute of Marine Research (IIM‐CSIC) Vigo Spain
| | - Paula Suarez‐Bregua
- Department of Biotechnology & Aquaculture, FishBioTech Lab. Institute of Marine Research (IIM‐CSIC) Vigo Spain
| | - Ingo Braasch
- Department of Integrative Biology, Program in Ecology, Evolutionary Biology and Behavior Michigan State University East Lansing MI USA
| | - Uwe Irion
- Max‐Planck‐Institute of Developmental Biology Tübingen Germany
| | - Robert Kelsh
- Department of Biology and Biochemistry, Centre for Regenerative Medicine University of Bath Bath UK
| | - Jose Miguel Cerdá‐Reverter
- Department of Fish Physiology and Biotechnology Institute of Aquaculture from Torre la Sal (IATS‐CSIC) Castellon Spain
| | - Josep Rotllant
- Department of Biotechnology & Aquaculture, FishBioTech Lab. Institute of Marine Research (IIM‐CSIC) Vigo Spain
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11
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Targeting MC1R depalmitoylation to prevent melanomagenesis in redheads. Nat Commun 2019; 10:877. [PMID: 30787281 PMCID: PMC6382811 DOI: 10.1038/s41467-019-08691-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/24/2019] [Indexed: 11/23/2022] Open
Abstract
Some genetic melanocortin-1 receptor (MC1R) variants responsible for human red hair color (RHC-variants) are consequently associated with increased melanoma risk. Although MC1R signaling is critically dependent on its palmitoylation primarily mediated by the ZDHHC13 protein-acyl transferase, whether increasing MC1R palmitoylation represents a viable therapeutic target to limit melanomagenesis in redheads is unknown. Here we identify a specific and efficient in vivo strategy to induce MC1R palmitoylation for therapeutic benefit. We validate the importance of ZDHHC13 to MC1R signaling in vivo by targeted expression of ZDHHC13 in C57BL/6J-MC1RRHC mice and subsequently inhibit melanomagenesis. By identifying APT2 as the MC1R depalmitoylation enzyme, we are able to demonstrate that administration of the selective APT2 inhibitor ML349 treatment efficiently increases MC1R signaling and represses UVB-induced melanomagenesis in vitro and in vivo. Targeting APT2, therefore, represents a preventive/therapeutic strategy to reduce melanoma risk, especially in individuals with red hair. Melanocortin-1 receptor is a palmitoylated protein and variants of the receptor are associated with red hair colour and susceptibility to melanoma. Here, the authors describe a method to enhance the palmitoylation of the receptor, which can inhibit melanomagenesis in mice.
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12
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Anello M, Daverio MS, Silbestro MB, Vidal-Rioja L, Di Rocco F. Characterization and expression analysis of KIT and MITF-M genes in llamas and their relation to white coat color. Anim Genet 2019; 50:143-149. [PMID: 30730042 DOI: 10.1111/age.12769] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2018] [Indexed: 11/27/2022]
Abstract
The llama (Lama glama) is a fiber-producing species that presents a wide range of coat colors, among which white is one of the most important for the textile industry. However, there is little information about the molecular mechanisms that control the white phenotype in this species. In domestic mammals, a white coat is usually produced by mutations in the KIT proto-oncogene receptor tyrosine kinase (KIT) and microphthalmia-associated transcription factor (MITF) genes. In this work we have sequenced and described the coding regions of KIT and MITF-M, the melanocyte-specific isoform, and the two transcriptional variants MITF-M(-) and MITF-M(+). Moreover, we studied the expression of these genes in the skin of white and colored llamas. Although no variants were revealed to be associated with white coat color, significant differences between phenotypes were observed in the expression levels of KIT and MITF-M. Interestingly, white llamas expressed less MITF-M(+) than did colored ones, which is consistent with a consequent reduction in the synthesis of melanin. Even though our results indicate that downregulation of KIT and MITF-M expression is involved in white phenotype production in llamas, the causative gene of white coat color remains unknown.
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Affiliation(s)
- M Anello
- Laboratorio de Genética Molecular, Instituto Multidisciplinario de Biología Celular (IMBICE), CONICET-UNLP-CIC, Calle 526 e/10 y 11, La Plata, 1900, Buenos Aires, Argentina
| | - M S Daverio
- Laboratorio de Genética Molecular, Instituto Multidisciplinario de Biología Celular (IMBICE), CONICET-UNLP-CIC, Calle 526 e/10 y 11, La Plata, 1900, Buenos Aires, Argentina
| | - M B Silbestro
- Laboratorio de Genética Molecular, Instituto Multidisciplinario de Biología Celular (IMBICE), CONICET-UNLP-CIC, Calle 526 e/10 y 11, La Plata, 1900, Buenos Aires, Argentina
| | - L Vidal-Rioja
- Laboratorio de Genética Molecular, Instituto Multidisciplinario de Biología Celular (IMBICE), CONICET-UNLP-CIC, Calle 526 e/10 y 11, La Plata, 1900, Buenos Aires, Argentina
| | - F Di Rocco
- Laboratorio de Genética Molecular, Instituto Multidisciplinario de Biología Celular (IMBICE), CONICET-UNLP-CIC, Calle 526 e/10 y 11, La Plata, 1900, Buenos Aires, Argentina
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Masselink W, Reumann D, Murawala P, Pasierbek P, Taniguchi Y, Bonnay F, Meixner K, Knoblich JA, Tanaka EM. Broad applicability of a streamlined ethyl cinnamate-based clearing procedure. Development 2019; 146:dev.166884. [PMID: 30665888 DOI: 10.1242/dev.166884] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 01/09/2019] [Indexed: 12/21/2022]
Abstract
Turbidity and opaqueness are inherent properties of tissues that limit the capacity to acquire microscopic images through large tissues. Creating a uniform refractive index, known as tissue clearing, overcomes most of these issues. These methods have enabled researchers to image large and complex 3D structures with unprecedented depth and resolution. However, tissue clearing has been adopted to a limited extent due to a combination of cost, time, complexity of existing methods and potential negative impact on fluorescence signal. Here, we describe 2Eci (2nd generation ethyl cinnamate-based clearing), which can be used to clear a wide range of tissues in several species, including human organoids, Drosophila melanogaster, zebrafish, axolotl and Xenopus laevis, in as little as 1-5 days, while preserving a broad range of fluorescent proteins, including GFP, mCherry, Brainbow and Alexa-conjugated fluorophores. Ethyl cinnamate is non-toxic and can easily be used in multi-user microscope facilities. This method opens up tissue clearing to a much broader group of researchers due to its ease of use, the non-toxic nature of ethyl cinnamate and broad applicability.
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Affiliation(s)
- Wouter Masselink
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-BioCenter 1, 1030 Vienna, Austria
| | - Daniel Reumann
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Prayag Murawala
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-BioCenter 1, 1030 Vienna, Austria
| | - Pawel Pasierbek
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Yuka Taniguchi
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-BioCenter 1, 1030 Vienna, Austria
| | - François Bonnay
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Katharina Meixner
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Jürgen A Knoblich
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Elly M Tanaka
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-BioCenter 1, 1030 Vienna, Austria
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14
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Wolf Horrell EM, Jarrett SG, Carter KM, D'Orazio JA. Divergence of cAMP signalling pathways mediating augmented nucleotide excision repair and pigment induction in melanocytes. Exp Dermatol 2017; 26:577-584. [PMID: 28094871 DOI: 10.1111/exd.13291] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2017] [Indexed: 12/14/2022]
Abstract
Loss-of-function melanocortin 1 receptor (MC1R) polymorphisms are common in UV-sensitive fair-skinned individuals and are associated with blunted cAMP second messenger signalling and higher lifetime risk of melanoma because of diminished ability of melanocytes to cope with UV damage. cAMP signalling positions melanocytes to resist UV injury by upregulating synthesis of UV-blocking eumelanin pigment and by enhancing the repair of UV-induced DNA damage. cAMP enhances melanocyte nucleotide excision repair (NER), the genome maintenance pathway responsible for the removal of mutagenic UV photolesions, through cAMP-activated protein kinase (protein kinase A)-mediated phosphorylation of the ataxia telangiectasia-mutated and Rad3-related (ATR) protein on the S435 residue. We investigated the interdependence of cAMP-mediated melanin upregulation and cAMP-enhanced DNA repair in primary human melanocytes and a melanoma cell line. We observed that the ATR-dependent molecular pathway linking cAMP signalling to the NER pathway is independent of MITF activation. Similarly, cAMP-mediated upregulation of pigment synthesis is independent of ATR, suggesting that the key molecular events driving MC1R-mediated enhancement of genome maintenance (eg PKA-mediated phosphorylation of ATR) and MC1R-induced pigment induction (eg MITF activation) are distinct.
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Affiliation(s)
- Erin M Wolf Horrell
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Stuart G Jarrett
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Katharine M Carter
- Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA
| | - John A D'Orazio
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, USA.,Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY, USA
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15
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Wolf Horrell EM, Boulanger MC, D’Orazio JA. Melanocortin 1 Receptor: Structure, Function, and Regulation. Front Genet 2016; 7:95. [PMID: 27303435 PMCID: PMC4885833 DOI: 10.3389/fgene.2016.00095] [Citation(s) in RCA: 134] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/13/2016] [Indexed: 01/04/2023] Open
Abstract
The melanocortin 1 receptor (MC1R) is a melanocytic Gs protein coupled receptor that regulates skin pigmentation, UV responses, and melanoma risk. It is a highly polymorphic gene, and loss of function correlates with a fair, UV-sensitive, and melanoma-prone phenotype due to defective epidermal melanization and sub-optimal DNA repair. MC1R signaling, achieved through adenylyl cyclase activation and generation of the second messenger cAMP, is hormonally controlled by the positive agonist melanocortin, the negative agonist agouti signaling protein, and the neutral antagonist β-defensin 3. Activation of cAMP signaling up-regulates melanin production and deposition in the epidermis which functions to limit UV penetration into the skin and enhances nucleotide excision repair (NER), the genomic stability pathway responsible for clearing UV photolesions from DNA to avoid mutagenesis. Herein we review MC1R structure and function and summarize our laboratory's findings on the molecular mechanisms by which MC1R signaling impacts NER.
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Affiliation(s)
- Erin M. Wolf Horrell
- Department of Physiology, University of Kentucky College of MedicineLexington, KY, USA
| | - Mary C. Boulanger
- Markey Cancer Center, University of Kentucky College of MedicineLexington, KY, USA
| | - John A. D’Orazio
- Department of Physiology, University of Kentucky College of MedicineLexington, KY, USA
- Markey Cancer Center, University of Kentucky College of MedicineLexington, KY, USA
- Departments of Pediatrics, Toxicology and Cancer Biology, Physiology, and Pharmacology and Nutritional Sciences, University of Kentucky College of MedicineLexington, KY, USA
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Shi Z, Ji K, Yang S, Zhang J, Yao J, Dong C, Fan R. Biological characteristics of mouse skin melanocytes. Tissue Cell 2016; 48:114-20. [DOI: 10.1016/j.tice.2016.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 01/04/2016] [Indexed: 01/28/2023]
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17
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Jang MH, Ahn TW. Inhibitory effects of Taraxacum mongolicum with phreatic water on melanin synthesis. Integr Med Res 2015; 4:76-93. [PMID: 28664113 PMCID: PMC5481772 DOI: 10.1016/j.imr.2014.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 08/19/2014] [Accepted: 08/25/2014] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Recently, people have begun showing heightened interest in skin whitening. Melanin is an important factor that determines skin color. The purpose of this study is to investigate the inhibitory effect of Taraxacum mongolicum (TAM) with phreatic water (PW) from Dogo Hot Springs on melanin synthesis. METHODS We assessed the inhibitory effects of TAM on melanin synthesis in B16F10 mouse melanoma cells. The mRNA levels of tyrosinase related protein (TRP)-1, TRP-2, tyrosinase, MITF, ERK, and PKA protein were analyzed with reverse transcription polymerase chain reaction and Western blot analysis. We also assessed the inhibitory effects of TAM with PW on melanin synthesis in HRM-2 melanin-possessing hairless mice. After UVB irradiation, differences in melanin were analyzed with an image analysis software between the left dorsal skin (untreated part) and the right dorsal skin (treated part). The mRNA levels of TRP-1, TRP-2, and matrix metalloproteinase (MMP)-9 were analyzed with real-time quantitative polymerase chain reaction. The dorsal skins were analyzed with histological test by hematoxylin and eosin staining. RESULTS TAM inhibited the TRP-1, TRP-2, tyrosinase, MITF mRNA gene expression, and PKA protein expression on the concentration-dependent B16F10 cell. Moreover, TAM increased the ERK mRNA gene expression in the B16F10 cell. After UVB irradiation, TAM with PW increased the differences in melanin between the left dorsal skin (untreated part) and the right dorsal skin (treated part) in HRM-2 mice. TAM with PW inhibited the TRP-1, TRP-2, and MMP-9 mRNA gene expression in HRM-2 mice. TAM with PW decreased the epidermal thickness, around the cell deformation, keratinization, and infiltration in HRM-2 mice. CONCLUSION These results indicate that TAM with PW has the inhibitory effect of decreasing the melanin synthesis.
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Affiliation(s)
- Moon-Hee Jang
- Department of Sasang Constitutional Medicine, Cheonan Oriental Hospital of Daejeon University, Cheonan, Korea
- Hot Spring Medicine Laboratory, Daejeon University, Cheonan, Korea
| | - Taek-Won Ahn
- Department of Sasang Constitutional Medicine, Cheonan Oriental Hospital of Daejeon University, Cheonan, Korea
- Hot Spring Medicine Laboratory, Daejeon University, Cheonan, Korea
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18
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Fulgione D, Lega C, Trapanese M, Buglione M. Genetic factors implied in melanin‐based coloration of the Italian wall lizard. J Zool (1987) 2015. [DOI: 10.1111/jzo.12242] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- D. Fulgione
- Department of Biology University of Naples ‘Federico II’ Napoli Italy
| | - C. Lega
- Department of Biology University of Naples ‘Federico II’ Napoli Italy
- Department of Earth Science University of Pisa Pisa Italy
| | - M. Trapanese
- Department of Biology University of Naples ‘Federico II’ Napoli Italy
| | - M. Buglione
- Department of Biology University of Naples ‘Federico II’ Napoli Italy
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19
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Ceinos RM, Guillot R, Kelsh RN, Cerdá-Reverter JM, Rotllant J. Pigment patterns in adult fish result from superimposition of two largely independent pigmentation mechanisms. Pigment Cell Melanoma Res 2014; 28:196-209. [PMID: 25469713 DOI: 10.1111/pcmr.12335] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 11/25/2014] [Indexed: 12/22/2022]
Abstract
Dorso-ventral pigment pattern differences are the most widespread pigmentary adaptations in vertebrates. In mammals, this pattern is controlled by regulating melanin chemistry in melanocytes using a protein, agouti-signalling peptide (ASIP). In fish, studies of pigment patterning have focused on stripe formation, identifying a core striping mechanism dependent upon interactions between different pigment cell types. In contrast, mechanisms driving the dorso-ventral countershading pattern have been overlooked. Here, we demonstrate that, in fact, zebrafish utilize two distinct adult pigment patterning mechanisms - an ancient dorso-ventral patterning mechanism, and a more recent striping mechanism based on cell-cell interactions; remarkably, the dorso-ventral patterning mechanism also utilizes ASIP. These two mechanisms function largely independently, with resultant patterns superimposed to give the full pattern.
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Affiliation(s)
- Rosa M Ceinos
- Aquatic Molecular Pathobiology Group, Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Cientificas (CSIC), Vigo, Spain
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20
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Nasti TH, Timares L. MC1R, eumelanin and pheomelanin: their role in determining the susceptibility to skin cancer. Photochem Photobiol 2014; 91:188-200. [PMID: 25155575 DOI: 10.1111/php.12335] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Accepted: 08/17/2014] [Indexed: 12/16/2022]
Abstract
Skin pigmentation is due to the accumulation of two types of melanin granules in the keratinocytes. Besides being the most potent blocker of ultraviolet radiation, the role of melanin in photoprotection is complex. This is because one type of melanin called eumelanin is UV absorbent, whereas the other, pheomelanin, is photounstable and may even promote carcinogenesis. Skin hyperpigmentation may be caused by stress or exposure to sunlight, which stimulates the release of α-melanocyte stimulating hormone (α-MSH) from damaged keratinocytes. Melanocortin 1 receptor (MC1R) is a key signaling molecule on melanocytes that responds to α-MSH by inducing expression of enzymes responsible for eumelanin synthesis. Persons with red hair have mutations in the MC1R causing its inactivation; this leads to a paucity of eumelanin production and makes red-heads more susceptible to skin cancer. Apart from its effects on melanin production, the α-MSH/MC1R signaling is also a potent anti-inflammatory pathway and has been shown to promote antimelanoma immunity. This review will focus on the role of MC1R in terms of its regulation of melanogenesis and influence on the immune system with respect to skin cancer susceptibility.
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Affiliation(s)
- Tahseen H Nasti
- The Department of Dermatology, University of Alabama at Birmingham School of Medicine, Birmingham, AL
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21
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García-Borrón JC, Abdel-Malek Z, Jiménez-Cervantes C. MC1R, the cAMP pathway, and the response to solar UV: extending the horizon beyond pigmentation. Pigment Cell Melanoma Res 2014; 27:699-720. [PMID: 24807163 DOI: 10.1111/pcmr.12257] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 05/01/2014] [Indexed: 12/20/2022]
Abstract
The melanocortin 1 receptor (MC1R) is a G protein-coupled receptor crucial for the regulation of melanocyte proliferation and function. Upon binding melanocortins, MC1R activates several signaling cascades, notably the cAMP pathway leading to synthesis of photoprotective eumelanin. Polymorphisms in the MC1R gene are a major source of normal variation of human hair color and skin pigmentation, response to ultraviolet radiation (UVR), and skin cancer susceptibility. The identification of a surprisingly high number of MC1R natural variants strongly associated with pigmentary phenotypes and increased skin cancer risk has prompted research on the functional properties of the wild-type receptor and frequent mutant alleles. We summarize current knowledge on MC1R structural and functional properties, as well as on its intracellular trafficking and signaling. We also review the current knowledge about the function of MC1R as a skin cancer, particularly melanoma, susceptibility gene and how it modulates the response of melanocytes to UVR.
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Affiliation(s)
- Jose C García-Borrón
- Department of Biochemistry and Molecular Biology, School of Medicine, University of Murcia, Murcia, Spain; Instituto Murciano de Investigación Biomédica (IMIB), El Palmar, Murcia, Spain
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22
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Haase B, Signer-Hasler H, Binns MM, Obexer-Ruff G, Hauswirth R, Bellone RR, Burger D, Rieder S, Wade CM, Leeb T. Accumulating mutations in series of haplotypes at the KIT and MITF loci are major determinants of white markings in Franches-Montagnes horses. PLoS One 2013; 8:e75071. [PMID: 24098679 PMCID: PMC3787084 DOI: 10.1371/journal.pone.0075071] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 07/24/2013] [Indexed: 11/18/2022] Open
Abstract
Coat color and pattern variations in domestic animals are frequently inherited as simple monogenic traits, but a number are known to have a complex genetic basis. While the analysis of complex trait data remains a challenge in all species, we can use the reduced haplotypic diversity in domestic animal populations to gain insight into the genomic interactions underlying complex phenotypes. White face and leg markings are examples of complex traits in horses where little is known of the underlying genetics. In this study, Franches-Montagnes (FM) horses were scored for the occurrence of white facial and leg markings using a standardized scoring system. A genome-wide association study (GWAS) was performed for several white patterning traits in 1,077 FM horses. Seven quantitative trait loci (QTL) affecting the white marking score with p-values p≤10(-4) were identified. Three loci, MC1R and the known white spotting genes, KIT and MITF, were identified as the major loci underlying the extent of white patterning in this breed. Together, the seven loci explain 54% of the genetic variance in total white marking score, while MITF and KIT alone account for 26%. Although MITF and KIT are the major loci controlling white patterning, their influence varies according to the basic coat color of the horse and the specific body location of the white patterning. Fine mapping across the MITF and KIT loci was used to characterize haplotypes present. Phylogenetic relationships among haplotypes were calculated to assess their selective and evolutionary influences on the extent of white patterning. This novel approach shows that KIT and MITF act in an additive manner and that accumulating mutations at these loci progressively increase the extent of white markings.
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Affiliation(s)
- Bianca Haase
- Faculty of Veterinary Science, University of Sydney, Sydney, New South Wales, Australia
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- * E-mail:
| | - Heidi Signer-Hasler
- Department of Agriculture, Forestry, Food Science and Management, Bern University of Applied Science, Zollikofen, Switzerland
| | | | | | - Regula Hauswirth
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Rebecca R. Bellone
- Department of Biology, University of Tampa, Tampa, Florida, United States of America
| | - Dominik Burger
- Swiss Institute of Equine Medicine, ALP-Haras and University of Bern, Avenches, Switzerland
| | - Stefan Rieder
- Agroscope ALP-Haras Research Station, Swiss National Stud Farm, Avenches, Switzerland
| | - Claire M. Wade
- Faculty of Veterinary Science, University of Sydney, Sydney, New South Wales, Australia
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- DermFocus, University of Bern, Bern, Switzerland
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Lin S, Foley J, Jiang T, Yeh C, Wu P, Foley A, Yen C, Huang Y, Cheng H, Chen C, Reeder B, Jee S, Widelitz R, Chuong C. Topology of feather melanocyte progenitor niche allows complex pigment patterns to emerge. Science 2013; 340:1442-5. [PMID: 23618762 PMCID: PMC4144997 DOI: 10.1126/science.1230374] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Color patterns of bird plumage affect animal behavior and speciation. Diverse patterns are present in different species and within the individual. Here, we study the cellular and molecular basis of feather pigment pattern formation. Melanocyte progenitors are distributed as a horizontal ring in the proximal follicle, sending melanocytes vertically up into the epithelial cylinder, which gradually emerges as feathers grow. Different pigment patterns form by modulating the presence, arrangement, or differentiation of melanocytes. A layer of peripheral pulp further regulates pigmentation via patterned agouti expression. Lifetime feather cyclic regeneration resets pigment patterns for physiological needs. Thus, the evolution of stem cell niche topology allows complex pigment patterning through combinatorial co-option of simple regulatory mechanisms.
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Affiliation(s)
- S.J. Lin
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei, Taiwan
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Genomes and Systems Biology Program and Center for Systems Biology, National Taiwan University, Taipei, Taiwan
| | - J. Foley
- Department of Medical Sciences, Indiana University School of Medicine, Bloomington, Indiana, USA
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - T.X. Jiang
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - C.Y. Yeh
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - P. Wu
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - A. Foley
- Foley Family Farm, Unionville, Indiana, USA
| | - C.M. Yen
- Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei, Taiwan
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - Y.C. Huang
- Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, Taipei, Taiwan
| | - H.C. Cheng
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan
- Center for the Integrative and Evolutionary Galliformes Genomics, iEGG Center, National Chung Hsing University, Taichung, Taiwan
| | - C.F. Chen
- Center for the Integrative and Evolutionary Galliformes Genomics, iEGG Center, National Chung Hsing University, Taichung, Taiwan
- Department of Animal Science, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung, Taiwan
| | - B. Reeder
- Independent researcher and author, London, Kentucky, USA
| | - S.H. Jee
- Department of Dermatology, National Taiwan University Hospital and College of Medicine, Taipei, Taiwan
| | - R.B. Widelitz
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - C.M. Chuong
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Center for the Integrative and Evolutionary Galliformes Genomics, iEGG Center, National Chung Hsing University, Taichung, Taiwan
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Guillot R, Ceinos RM, Cal R, Rotllant J, Cerdá-Reverter JM. Transient ectopic overexpression of agouti-signalling protein 1 (asip1) induces pigment anomalies in flatfish. PLoS One 2012; 7:e48526. [PMID: 23251332 PMCID: PMC3519472 DOI: 10.1371/journal.pone.0048526] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 10/01/2012] [Indexed: 12/23/2022] Open
Abstract
While flatfish in the wild exhibit a pronounced countershading of the dorso-ventral pigment pattern, malpigmentation is commonly observed in reared animals. In fish, the dorso-ventral pigment polarity is achieved because a melanization inhibition factor (MIF) inhibits melanoblast differentiation and encourages iridophore proliferation in the ventrum. A previous work of our group suggested that asip1 is the uncharacterized MIF concerned. In order to further support this hypothesis, we have characterized asip1 mRNAs in both turbot and sole and used deduced peptide alignments to analyze the evolutionary history of the agouti-family of peptides. The putative asip precursors have the characteristics of a secreted protein, displaying a putative hydrophobic signal. Processing of the potential signal peptide produces mature proteins that include an N-terminal region, a basic central domain with a high proportion of lysine residues as well as a proline-rich region that immediately precedes the C-terminal poly-cysteine domain. The expression of asip1 mRNA in the ventral area was significantly higher than in the dorsal region. Similarly, the expression of asip1 within the unpigmented patches in the dorsal skin of pseudoalbino fish was higher than in the pigmented dorsal regions but similar to those levels observed in the ventral skin. In addition, the injection/electroporation of asip1 capped mRNA in both species induced long term dorsal skin paling, suggesting the inhibition of the melanogenic pathways. The data suggest that fish asip1 is involved in the dorsal-ventral pigment patterning in adult fish, where it induces the regulatory asymmetry involved in precursor differentiation into mature chromatophore. Adult dorsal pseudoalbinism seems to be the consequence of the expression of normal developmental pathways in an inaccurate position that results in unbalanced asip1 production levels. This, in turn, generates a ventral-like differentiation environment in dorsal regions.
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Affiliation(s)
- Raúl Guillot
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre de la Sal, Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
| | - Rosa Maria Ceinos
- Aquatic Molecular Pathobiology Group, Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Científicas (IIM-CSIC), Vigo, Spain
| | - Rosa Cal
- Instituto Español de Oceanografía de Vigo (IEO), Vigo, Spain
| | - Josep Rotllant
- Aquatic Molecular Pathobiology Group, Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Científicas (IIM-CSIC), Vigo, Spain
| | - José Miguel Cerdá-Reverter
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre de la Sal, Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
- * E-mail:
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25
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Park KH, Lee MW. Anti-oxidative, anti-inflammatory and whitening effects of phenolic compounds from Bambusae Caulis in Liquamen. Nat Prod Res 2011; 26:1687-91. [PMID: 21985061 DOI: 10.1080/14786419.2011.593517] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Bambusae Caulis in Liquamen (BCL) is the distilled product of the condensation from the burning of Phyllostachys nigra var. henosis (Gramineae). The activity-guided isolation of BCL yielded four phenolic compounds: 2,6-dimethoxyphenol (1), 1,2-dihydroxybenzene (2), 1,3-dihydroxybenzene (3) and 1,2-dibenzenecarboxylic acid (4). We evaluated the anti-oxidative, anti-inflammatory and whitening effects of these compounds, via assays, of 1,1-diphenyl-2-picrylhydazyl (DPPH) radical scavenging activity and inhibition of nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells as well as inhibition of tyrosinase activity and melanin production in B16F10 melanoma cells. The results showed that 2 and 3 exhibited significant DPPH radical scavenging activity as well as inhibitory effects on NO production, tyrosinase activity and melanin production. These results suggested that BCL and compounds 2 and 3 can be developed as anti-oxidative, anti-inflammatory and whitening ingredients.
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Affiliation(s)
- Kwan Hee Park
- College of Pharmacy, Chung-Ang University, Seoul 156-756, South Korea
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Cerdá-Reverter JM, Agulleiro MJ, R RG, Sánchez E, Ceinos R, Rotllant J. Fish melanocortin system. Eur J Pharmacol 2011; 660:53-60. [DOI: 10.1016/j.ejphar.2010.10.108] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2010] [Revised: 09/30/2010] [Accepted: 10/12/2010] [Indexed: 12/26/2022]
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Nitric oxide enhances melanogenesis of alpaca skin melanocytes in vitro by activating the MITF phosphorylation. Mol Cell Biochem 2011; 352:255-60. [PMID: 21431368 DOI: 10.1007/s11010-011-0761-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Accepted: 02/17/2011] [Indexed: 10/18/2022]
Abstract
Ultraviolet (UV) B radiation can cause skin-tanning via the synthesis of melanin which is synthesized by specific tyrosinase and tyrosinase-related enzymes expressed in melanocytes. It is reported that several melanogenic factors are released from keratinocytes and other cells surrounding melanocytes in the skin following UV radiation. Some of them are reported to up-regulate tyrosinase gene expression through a different pathway, but most regulate tyrosinase via microphthalmia-associated transcription factor (MITF). It is unknown whether an NO-induced pathway regulates melanogenesis via MITF in vitro. In this study, we investigated this problem because it is important for our understanding of how to enhance the coat color of alpaca. We set up three groups for experiments using alpaca melanocytes: the control cultures were allowed a total of 5 days growth; the UV group cultures were also allowed 5 days of growth like the control group, but were then irradiated once everyday with 312 mJ/cm(2) of UVB; the UV + L-NAME group was the same as the UV group, but with the addition of 300 μM L-NAME every 6 h. To determine the NO inhibition effect, NO product was measured. To determine the effect of NO on MITF, the expression levels of the MITF gene and protein were measured by immunofluorescence, quantitative real-time PCR and western immunoblotting. To determine the influence of NO on MITF phosphorylation, phosphorylated MITF protein (p-MITF) was measured by western immunoblotting. To determine the effect of NO on melanogenesis, the melanin content was measured. The results provide exciting new evidence that NO can enhance melanogenesis in alpaca skin melanocytes by stimulating MITF phosphorylation.
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Kondo T, Hearing VJ. Update on the regulation of mammalian melanocyte function and skin pigmentation. EXPERT REVIEW OF DERMATOLOGY 2011; 6:97-108. [PMID: 21572549 PMCID: PMC3093193 DOI: 10.1586/edm.10.70] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Melanogenesis is the unique process of producing pigmented biopolymers that are sequestered within melanosomes, which provides color to the skin, hair and eyes of animals and, in the case of human skin, also protects the underlying tissues from UV damage. We review the current understanding of melanogenesis, focusing on factors important to the biochemistry of pigment synthesis, the biogenesis of melanosomes, signaling pathways and factors that regulate melanogenesis, intramelanosomal pH, transport and transfer of melanosomes, and pigmentary disorders related to the dysfunction of melanosome-related proteins. Although it has been known for some time that many of the factors that affect melanogenesis are derived from keratinocytes, fibroblasts, endothelial cells, hormones, inflammatory cells and nerves, a number of new factors that are involved in that regulation have recently been reported, such as factors that regulate melanosome pH and ion transport.
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Affiliation(s)
- Taisuke Kondo
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Vincent J Hearing
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Lee JE, Kim SY, Jeong YM, Yun HY, Baek KJ, Kwon NS, Park KC, Kim DS. The regulatory mechanism of melanogenesis by FTY720, a sphingolipid analogue. Exp Dermatol 2010; 20:237-41. [DOI: 10.1111/j.1600-0625.2010.01148.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Expression and network analysis of genes related to melanocyte development in the Silky Fowl and White Leghorn embryos. Mol Biol Rep 2010; 38:1433-41. [PMID: 20848220 DOI: 10.1007/s11033-010-0248-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2009] [Accepted: 09/02/2010] [Indexed: 10/19/2022]
Abstract
Silky Fowl is a natural mutant with hyperpigmentation of various internal tissues. Although the mechanism of hyperpigmentation remains unclear, recent studies have shown that the abnormal migration of melanoblast and the absence of environmental barrier molecules are responsible for the hyperpigmentation in Silky Fowl. In this study, 13 genes related to melanocyte development were selected to detect expression changes between Silky Fowl and White Leghorn [including SRY-box 10 (Sox10), paired box (Pax3), stem cell factor (Scf), v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (Kit), endothelin type-B receptor (Ednrb), endothelin 3 (Edn3), microphthalmia-associated transcription factor (Mitf), tyrosinase (Tyr), tyrosinase-related protein-1 (Trp1), tyrosinase-related protein-2 (Trp2), melanocortin-1 receptor (Mc1r), Agouti-related proteins (Agrp), and Proopiomelanocortin (Pomc)]. Transcript expression was detected in 11 stages from 2.5 to 15 days of incubation. In these embryonic periods, Mitf, Kit, Scf, and Agrp expressed earlier in Silky Fowl than in White Leghorn. Sox10, Ednrb, Kit, Mc1r, and Agrp, associating with the proliferation and differentiation of melanoblast, expressed higher (P < 0.05) in Silky Fowl than White Leghorn during 5-6 days of incubation. After day 8 of incubation, Mitf, Tyr, Trp1, Trp2, and Mc1r expressed higher (P < 0.05) in Silky Fowl than White Leghorn, while Agrp expressed higher (P < 0.05) in White Leghorn than Silky Fowl. Moreover, a regulatory network for melanocyte development was constructed based on the expression data. The network predicted novel regulatory relationships and confirmed relationships that have been reported. These results provide biological insight into the molecular mechanism of hyperpigmentation in the Silky Fowl. However, further investigation is needed to confirm these regulatory relationships.
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Eskandani M, Golchai J, Pirooznia N, Hasannia S. Oxidative stress level and tyrosinase activity in vitiligo patients. Indian J Dermatol 2010; 55:15-9. [PMID: 20418970 PMCID: PMC2856366 DOI: 10.4103/0019-5154.60344] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background: Vitiligo is an acquired pigmentary disorder of the skin. Genetic factors, oxidative stress, autoimmunity, and neurochemical agents might be contributing factors for the development of the disease. Aims: To evaluate the oxidative stress level and tyrosinase activity in vitiligo patients and to compare them with healthy volunteers. Materials and Methods: We used Comet assay to evaluate DNA strand breaks in peripheral blood cells of active vitiligo patients. We then extracted total protein from lesional and nonlesional skin of ten selected patients. Tyrosinase activity was found to play a crucial role in melanogenesis. Results: The basal level of systemic oxidative DNA strand breaks in leukocytes increased in vitiligo patients compared to healthy participants. We observed that tyrosinase activity in lesional skin was lower than in nonlesional skin. Conclusion: Our finding suggests that increased levels of oxidative stress might impact tyrosinase activity and eumelanin synthesis via anabolism pathway of melanin synthesis. In sum, we observed a negative correlation between levels of systemic oxidative stress and of tyrosinase activity.
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Walker WP, Gunn TM. Shades of meaning: the pigment-type switching system as a tool for discovery. Pigment Cell Melanoma Res 2010; 23:485-95. [PMID: 20465596 DOI: 10.1111/j.1755-148x.2010.00721.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The pigment-type switching system, which controls whether melanocytes produce black/brown eumelanin or yellow/red pheomelanin, is responsible for many familiar coat coloration patterns in both domestic and wild mammals. In conjunction with the accessory proteins attractin and mahogunin ring finger 1, endogenous agonists and antagonists modulate signaling by the melanocortin 1 receptor to determine pigment type. Mutations in pigment-type switching genes can cause a variety of pleiotropic phenotypes, and these are often similar between mutants at different loci because the proteins encoded by these genes act together as part of conserved molecular pathways that are deployed in multiple biological contexts. When this is the case, pigment-type switching provides a powerful model system for elucidating the shared molecular mechanisms underlying the pigmentary and non-pigmentary phenotypes. This review outlines the current understanding of the pigment-type switching pathway and discusses the opportunities that exist for exploring the molecular basis of pleiotropic phenotypes using this model system.
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Vachtenheim J, Borovanský J. “Transcription physiology” of pigment formation in melanocytes: central role of MITF. Exp Dermatol 2010; 19:617-27. [PMID: 20201954 DOI: 10.1111/j.1600-0625.2009.01053.x] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Sánchez E, Rubio VC, Cerdá-Reverter JM. Molecular and pharmacological characterization of the melanocortin type 1 receptor in the sea bass. Gen Comp Endocrinol 2010; 165:163-9. [PMID: 19539622 DOI: 10.1016/j.ygcen.2009.06.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 06/04/2009] [Accepted: 06/12/2009] [Indexed: 12/27/2022]
Abstract
Melanocortin 1 receptor (MC1R) plays a key role in the physiology of the vertebrate pigment system. Point mutations producing hyperactive or inactive receptors result in darkening or paling effects, respectively. We report the molecular and pharmacological characterization, as well as the tissue expression pattern, of the sea bass Mc1r. Similar to other MC1Rs, the sea bass gene is highly polymorphic and nine DNA polymorphisms, seven of them involving an amino acid substitution, were detected. SbMc1r is mainly expressed in the testis, fat and liver with moderate levels in the ventral and dorsal skin. The sea bass receptor was activated by all the melanocortins tested, with ACTH showing the lowest efficiency. The acetylation level of the MSH isoforms seems to be critical for the effectively of the agonist. Agouti-related protein (AGRP) drastically inhibited the basal activity of the receptor in vitro, as an inverse agonist does, but only in the presence of phosphodiesterase inhibitors. This observation suggests that sbMc1r is constitutively activated and inversely regulated by AGRP, which is expressed in the skin of different fish species.
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Affiliation(s)
- E Sánchez
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre de la Sal, Ribera de Cabanes, Castellón, Spain
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35
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Hida T, Wakamatsu K, Sviderskaya EV, Donkin AJ, Montoliu L, Lynn Lamoreux M, Yu B, Millhauser GL, Ito S, Barsh GS, Jimbow K, Bennett DC. Agouti protein, mahogunin, and attractin in pheomelanogenesis and melanoblast-like alteration of melanocytes: a cAMP-independent pathway. Pigment Cell Melanoma Res 2009; 22:623-34. [PMID: 19493315 PMCID: PMC2784899 DOI: 10.1111/j.1755-148x.2009.00582.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Melanocortin-1 receptor (MC1R) and its ligands, α-melanocyte stimulating hormone (αMSH) and agouti signaling protein (ASIP), regulate switching between eumelanin and pheomelanin synthesis in melanocytes. Here we investigated biological effects and signaling pathways of ASIP. Melan-a non agouti (a/a) mouse melanocytes produce mainly eumelanin, but ASIP combined with phenylthiourea and extra cysteine could induce over 200-fold increases in the pheomelanin to eumelanin ratio, and a tan-yellow color in pelletted cells. Moreover, ASIP-treated cells showed reduced proliferation and a melanoblast-like appearance, seen also in melanocyte lines from yellow (Ay/a and Mc1re/ Mc1re) mice. However ASIP-YY, a C-terminal fragment of ASIP, induced neither biological nor pigmentary changes. As, like ASIP, ASIP-YY inhibited the cAMP rise induced by αMSH analog NDP-MSH, and reduced cAMP level without added MSH, the morphological changes and depigmentation seemed independent of cAMP signaling. Melanocytes genetically null for ASIP mediators attractin or mahogunin (Atrnmg-3J/mg-3J or Mgrn1md-nc/md-nc) also responded to both ASIP and ASIP-YY in cAMP level, while only ASIP altered their proliferation and (in part) shape. Thus, ASIP–MC1R signaling includes a cAMP-independent pathway through attractin and mahogunin, while the known cAMP-dependent component requires neither attractin nor mahogunin.
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Affiliation(s)
- Tokimasa Hida
- Division of Basic Medical Sciences, St. George's, University of London, Cranmer Terrace, London, UK
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36
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Jo HY, Kim CK, Suh IB, Ryu SW, Ha KS, Kwon YG, Kim YM. Co-localization of inducible nitric oxide synthase and phosphorylated Akt in the lesional skins of patients with melasma. J Dermatol 2009; 36:10-6. [PMID: 19207431 DOI: 10.1111/j.1346-8138.2008.00579.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Activation of the inducible nitric oxide synthase (iNOS)/nitric oxide (NO) pathway in keratinocytes has been reported to be associated with the pathogenesis of melanogenesis. Akt activation plays an important role in the activation of the transcription factor nuclear factor (NF)-kappaB and subsequent elevation of iNOS expression. In the present study, we highly detected both iNOS protein and Akt phosphorylation in keratinocytes of the basal layer of the epidermis at the junction with the dermis of melasma skin biopsy specimens, but not in normal skin tissues, from nine patients using immunohistological analysis. iNOS protein and phosphorylated Akt were co-localized in the lesional skins, and their levels were highly correlated R2= 0.69). Furthermore, iNOS mRNA was also detected in an additional three skin biopsy specimens, but not in normal skin, by reverse transcription polymerase chain reaction. Our results describe that iNOS expression is elevated in human melasma lesions, probably via activation of the Akt/NF-kappaB pathway, indicating that NO production plays an important role in the mechanism of hyperpigmentation in human facial melasma.
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Affiliation(s)
- Ho-Youn Jo
- Department of Dermatology, Kangwon National University, Chunchon, Kangwon-do, Korea
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37
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Le Pape E, Passeron T, Giubellino A, Valencia JC, Wolber R, Hearing VJ. Microarray analysis sheds light on the dedifferentiating role of agouti signal protein in murine melanocytes via the Mc1r. Proc Natl Acad Sci U S A 2009; 106:1802-7. [PMID: 19174519 PMCID: PMC2644118 DOI: 10.1073/pnas.0806753106] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Indexed: 12/27/2022] Open
Abstract
The melanocortin-1 receptor (MC1R) is a key regulator of pigmentation in mammals and is tightly linked to an increased risk of skin cancers, including melanoma, in humans. Physiologically activated by alpha-melanocyte stimulating hormone (alphaMSH), MC1R function can be antagonized by a secreted factor, agouti signal protein (ASP), which is responsible for the lighter phenotypes in mammals (including humans), and is also associated with increased risk of skin cancer. It is therefore of great interest to characterize the molecular effects elicited by those MC1R ligands. In this study, we determined the gene expression profiles of murine melan-a melanocytes treated with ASP or alphaMSH over a 4-day time course using genome-wide oligonucleotide microarrays. As expected, there were significant reductions in expression of numerous melanogenic proteins elicited by ASP, which correlates with its inhibition of pigmentation. ASP also unexpectedly modulated the expression of genes involved in various other cellular pathways, including glutathione synthesis and redox metabolism. Many genes up-regulated by ASP are involved in morphogenesis (especially in nervous system development), cell adhesion, and extracellular matrix-receptor interactions. Concomitantly, ASP enhanced the migratory potential and the invasiveness of melanocytic cells in vitro. These results demonstrate the role of ASP in the dedifferentiation of melanocytes, identify pigment-related genes targeted by ASP and by alphaMSH, and provide insights into the pleiotropic molecular effects of MC1R signaling that may function during development and may affect skin cancer risk.
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Affiliation(s)
- Elodie Le Pape
- Pigment Cell Biology Section, Laboratory of Cell Biology
| | | | - Alessio Giubellino
- Urologic Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892; and
| | | | - Rainer Wolber
- Beiersdorf AG, Research and Development, Skin Research Center, 20245 Hamburg, Germany
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Le Pape E, Wakamatsu K, Ito S, Wolber R, Hearing VJ. Regulation of eumelanin/pheomelanin synthesis and visible pigmentation in melanocytes by ligands of the melanocortin 1 receptor. Pigment Cell Melanoma Res 2008; 21:477-86. [PMID: 18627531 DOI: 10.1111/j.1755-148x.2008.00479.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The production of melanin in the hair and skin is tightly regulated by the melanocortin 1 receptor (MC1R) whose activation is controlled by two secreted ligands, alpha-melanocyte stimulating hormone (alphaMSH) and agouti signal protein (ASP). As melanin is extremely stable, lasting years in biological tissues, the mechanism underlying the relatively rapid decrease in visible pigmentation elicited by ASP is of obvious interest. In this study, the effects of ASP and alphaMSH on the regulation of melanin synthesis and on visible pigmentation were assessed in normal murine melanocytes and were compared with the quick depigmenting effect of the tyrosinase inhibitor, phenylthiourea (PTU). alphaMSH increased pheomelanin levels prior to increasing eumelanin content over 4 days of treatment. Conversely, ASP switched off the pigment synthesis pathway, reducing eu- and pheo-melanin synthesis within 1 day of treatment that was proportional to the decrease in tyrosinase protein level and activity. These results demonstrate that the visible depigmentation of melanocytes induced by ASP does not require the degradation of existing melanin but rather is due to the dilution of existing melanin by melanocyte turnover, which emphasizes the importance of pigment distribution to visible color.
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Affiliation(s)
- Elodie Le Pape
- Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Passeron T, Valencia JC, Bertolotto C, Hoashi T, Le Pape E, Takahashi K, Ballotti R, Hearing VJ. SOX9 is a key player in ultraviolet B-induced melanocyte differentiation and pigmentation. Proc Natl Acad Sci U S A 2007; 104:13984-9. [PMID: 17702866 PMCID: PMC1955778 DOI: 10.1073/pnas.0705117104] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SOX (SRY type HMG box) proteins are transcription factors that are predominantly known for their roles during development. During melanocyte development from the neural crest, SOX10 regulates microphthalmia-associated transcription factor, which controls a set of genes critical for pigment cell development and pigmentation, including dopachrome tautomerase and tyrosinase. We report here that another SOX factor, SOX9, is expressed by melanocytes in neonatal and adult human skin and is up-regulated by UVB exposure. We demonstrate that this regulation is mediated by cAMP and protein kinase. We also show that agouti signal protein, a secreted factor known to decrease pigmentation, down-regulates SOX9 expression. In adult and neonatal melanocytes, SOX9 regulates microphthalmia-associated transcription factor, dopachrome tautomerase, and tyrosinase promoters, leading to an increase in the expression of these key melanogenic proteins and finally to a stimulation of pigmentation. SOX9 completes the complex and tightly regulated process leading to the production of melanin by acting at a very upstream level. This role of SOX9 in pigmentation emphasizes the poorly understood impact of SOX proteins in adult tissues.
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Affiliation(s)
- Thierry Passeron
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
| | - Julio C. Valencia
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
| | - Corine Bertolotto
- Unité 597, Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine, Université de Nice Sophia–Antipolis, 06103 Nice, France
| | - Toshihiko Hoashi
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
| | - Elodie Le Pape
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
| | - Kaoruko Takahashi
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
| | - Robert Ballotti
- Unité 597, Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine, Université de Nice Sophia–Antipolis, 06103 Nice, France
| | - Vincent J. Hearing
- *Pigment Cell Biology Section, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20814; and
- To whom correspondence may be addressed.
Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Building 37, Room 2132, MSC 4256, Bethesda, MD 20892. E-mail:
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Ando H, Kondoh H, Ichihashi M, Hearing VJ. Approaches to Identify Inhibitors of Melanin Biosynthesis via the Quality Control of Tyrosinase. J Invest Dermatol 2007; 127:751-61. [PMID: 17218941 DOI: 10.1038/sj.jid.5700683] [Citation(s) in RCA: 245] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Tyrosinase, a copper-containing glycoprotein, is the rate-limiting enzyme critical for melanin biosynthesis in specialized organelles termed melanosomes that are produced only by melanocytic cells. Inhibitors of tyrosinase activity have long been sought as therapeutic means to treat cutaneous hyperpigmentary disorders. Multiple potential approaches exist that could control pigmentation via the regulation of tyrosinase activity, for example: the transcription of its messenger RNA, its maturation via glycosylation, its trafficking to melanosomes, as well as modulation of its catalytic activity and/or stability. However, relatively little attention has been paid to regulating pigmentation via the stability of tyrosinase, which depends on its processing and maturation in the endoplasmic reticulum and Golgi, its delivery to melanosomes and its degradation via the ubiquitin-proteasome pathway and/or the endosomal/lysosomal system. Recently, it has been shown that carbohydrate modification, molecular chaperone engagement, and ubiquitylation all play pivotal roles in regulating the degradation/stability of tyrosinase. While such processes affect virtually all proteins, such effects on tyrosinase have immediate and dramatic consequences on pigmentation. In this review, we classify melanogenic inhibitory factors in terms of their modulation of tyrosinase function and we summarize current understanding of how the quality control of tyrosinase processing impacts its stability and melanogenic activity.
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Affiliation(s)
- Hideya Ando
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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41
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Abstract
Among more than 120 genes that are now known to regulate mammalian pigmentation, one of the key genes is MC1R, which encodes the melanocortin 1 receptor, a seven transmembrane G protein-coupled receptor expressed on the surface of melanocytes. Since the monoexonic sequence of the gene was cloned and characterized more than a decade ago, tremendous efforts have been dedicated to the extensive genotyping of mostly red-haired populations all around the world, thus providing allelic variants that may or may not account for melanoma susceptibility in the presence or absence of ultraviolet (UV) exposure. Soluble factors, such as proopiomelanocortin (POMC) derivatives, agouti signal protein (ASP) and others, regulate MC1R expression, leading to improved photoprotection via increased eumelanin synthesis or in contrast, inducing the switch to pheomelanin. However, there is an obvious lack of knowledge regarding the numerous and complex regulatory mechanisms that govern the expression of MC1R at the intra-cellular level, from gene transcription in response to an external stimulus to the expression of the mature receptor on the melanocyte surface.
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Affiliation(s)
- Francois Rouzaud
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Building 37, Room 2132, Bethesda, MD 20892, USA
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Abstract
The first mouse microphthalmia transcription factor (Mitf ) mutation was discovered over 60 years ago, and since then over 24 spontaneous and induced mutations have been identified at the locus. Mitf encodes a member of the Myc supergene family of basic helix-loop-helix zipper (bHLH-Zip) transcription factors. Like Myc, Mitf regulates gene expression by binding to DNA as a homodimer or as a heterodimer with another related family member, in the case of Mitf the Tfe3, Tfeb, and Tfec proteins. The study of Mitf has provided many insights into the biology of melanocytes and helped to explain how melanocyte-specific gene expression and signaling is regulated. The human homologue of MITF is mutated in patients with the pigmentary and deafness disorder Waardenburg Syndrome Type 2A (WS2A). The mouse Mitf mutations therefore serve as a model for the study of this human disease. Mutations and/or aberrant expression of several MITF family member genes have also been reported in human cancer, including melanoma (MITF), papillary renal cell carcinoma (TFE3, TFEB), and alveolar soft part sarcoma (TFE3). Genes in the MITF/TFE pathway may therefore also represent valuable therapeutic targets for the treatment of human cancer. Here we review recent developments in the analysis of Mitf function in vivo and in vitro and show how traditional genetics, modern forward genetics and in vitro biochemical analyses have combined to produce an intriguing story on the role and actions of a gene family in a living organism.
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Affiliation(s)
- Eiríkur Steingrímsson
- Department of Biochemistry and Molecular Biology, University of Iceland, 101 Reykjavik, Iceland.
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Guida G, Zanna P, Gallone A, Argenzio E, Cicero R. Melanogenic response of the Kupffer cells of Rana esculenta L to melanocyte stimulating hormone. ACTA ACUST UNITED AC 2004; 17:128-34. [PMID: 15016301 DOI: 10.1046/j.1600-0749.2003.00118.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have previously shown that Kupffer cells (KCs) of Rana esculenta L. possess melanogenic ability. The melanogenic enzyme activities in these cells are different from those described in skin melanocytes, and very little is known about their regulation by extracellular signalling molecules. In order to study this regulation, we analysed the effects of NDP-MSH on the levels of expression of the tyrosinase gene and on dopa-oxidase activity, using primary cultures of KCs. Incubation of the cells with NDP-MSH increases tyrosinase gene transcription, within the first 24 h of stimulation. To gain insight into the signalling mechanism involved in the cell response to the hormone, KCs in culture were incubated with IBMX or forskolin. These agents mimic the effects of alpha-MSH on melanocytes by increasing the intracellular level of cAMP. The experimental results showed that while the hormonal treatment always activated the KC tyrosinase system, treatment with IBMX or forskolin never did. Therefore, in KCs the tyrosinase-stimulating action of NDP-MSH was not mimicked by cAMP elevating agents. Assays of cAMP levels in cells stimulated with NDP-MSH demonstrated that the hormone does not produce significant increases in intracellular cAMP. On the contrary, forskolin produced significant increases in cAMP starting from 30 min of incubation. These results suggest that tyrosinase induction by melanocortins in KCs is not mediated by the cAMP pathway, and highlight the existence of substantial differences in the hormone signal transduction mechanisms between amphibian KCs and melanocytes or melanoma cells.
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Affiliation(s)
- Gabriella Guida
- Dipartimento di Biochimica Medica e Biologia Medica, Sezione di Biologia Medica, Facoltà di Medicina e Chirurgia, Università degli Studi, Policlinico, Piazza Giulio Cesare, 70124 Bari, Italy
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Yang CH, Shen SC, Lee JC, Wu PC, Hsueh SF, Lu CY, Meng CT, Hong HS, Yang LC. Seeing the gene therapy: application of gene gun technique to transfect and decolour pigmented rat skin with human agouti signalling protein cDNA. Gene Ther 2004; 11:1033-9. [PMID: 15164092 DOI: 10.1038/sj.gt.3302264] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We developed a gene gun method for the transfer of human agouti signalling protein (ASP) cDNA to alter rat skin colour in vivo. Human ASP cDNA was cloned into a modified cytomegalovirus plasmid and delivered to the skin of Long-Evans rats by gene gun bombardment. Skin pigmentation, body weight and blood sugar of ASP cDNA-transfected rats were recorded against the control group, which were injected with plasmids encoding for green fluorescent protein. The treated skin showed lighter skin colour after 3 days of ASP gene transfection. This depigmentation effect was most prominent on day 14 and the skin gradually returned to its original pigmentation by day 28. Successful transfection of ASP gene in skin and hair follicles, as well as downregulation of melanocortin-1 receptor (MC1R) and tyrosinase expression upon treatment, was confirmed using immunohistochemistry and Western blot analysis. Body weight and blood sugar in the treated rats did not show statistically significant differences as compared to control groups. These observations demonstrate that gene transfer using the gene gun method can induce high cutaneous ASP production and facilitate a switch from dark to fair colour without systemic pleiotropic effects. Such a colour switch may be that ASP is acting in a paracrine fashion. In addition, this study verifies that ASP exerts its functions by acting as an independent ligand that downregulates the melanocyte MC1R and tyrosinase protein in an in vivo system. Our result offers new, interesting insights about the effect of ASP on pigmentation, providing a novel approach to study the molecular mechanisms underlying skin melanogenesis.
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Affiliation(s)
- C-H Yang
- Department of Dermatology, Chang Gung Memorial Hospital, Taipei, Taiwan
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Julé S, Bossé P, Egidy G, Panthier JJ. Establishment and characterization of a normal melanocyte cell line derived from pig skin. PIGMENT CELL RESEARCH 2003; 16:407-10. [PMID: 12859625 DOI: 10.1034/j.1600-0749.2003.00071.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Several minipig strains develop spontaneous malignant melanoma. As a first step toward the analysis of genes involved in the tumoral progression of melanoma in these animal models, we developed culture conditions for pig melanocytes whereby melanocytes from normal epidermis can be isolated directly onto mitotically inactivated keratinocytes in Eagle's minimal essential medium supplemented with fetal calf serum, tetradecanoyl phorbol acetate (TPA) and cholera toxin. We also derived an immortal line of pigmented melanocytes from the epidermis of a healthy Meishan pig. This cell line, designated PigMel, retains differentiation function in culture, dependence on TPA and cholera toxin and a diploid chromosome number. PigMel melanocytes exhibit morphological and molecular characteristics common to normal mammalian skin melanocytes.
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Affiliation(s)
- Sophia Julé
- UMR 955 INRA-ENVA de Génétique Moléculaire et Cellulaire, Laboratoire conventionné CEA no. 17V, Ecole Nationale Vétérinaire d'Alfort, 7 avenue de Général de Gaulle, Maisons-Alfort cedex, France
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Abstract
beta-Catenin is a multifunctional protein involved in cell-cell adhesion, intracellular signalling and gene transcription. It has been implicated in the development of various lineages, including neural crest derivatives. Melanocytes are derived from neural crest cells and beta-catenin is expressed throughout the development of this cell lineage. The multifunctional activity of beta-catenin is directly associated with its participation in multi protein-protein interactions. The cell-cell adhesion function of beta-catenin is mediated by the large cadherin cell adhesion molecule family, the intracellular signalling function by its interaction with GSK3beta, and the gene transcription activity by the four known LEF/TCF DNA binding-proteins. Here, we review the known beta-catenin interacting factors and targets involved in the development and transformation of melanocytes and in particular its role in the expression of the crucial gene of melanocyte development, Mitf.
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Affiliation(s)
- Lionel Larue
- Developmental Genetics of Melanocytes, CNRS-Institut Curie, Orsay Cedex, France.
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47
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Wolff GL. Regulation of yellow pigment formation in mice: a historical perspective. PIGMENT CELL RESEARCH 2003; 16:2-15. [PMID: 12519120 DOI: 10.1034/j.1600-0749.2003.00012.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Pigment synthesis by hair follicle melanocytes is modulated by a large number of environmental and genetic factors, many of which are discussed in this review. Eumelanic (non-yellow) pigment is produced by hair follicle melanocytes following the binding of alpha-melanocyte stimulating hormone to melanocortin receptor 1. Binding of this hormone to the melanocyte membrane is blocked by agouti signaling protein (ASP) which is encoded by the agouti locus and results in the synthesis of yellow pigment, instead of non-yellow (black/brown) pigment. The cyclical release of ASP by hair follicle cells results in a black/brown hair with a subapical yellow band. This is the wild-type coat color pattern of many mammals and is called agouti. Several dominant mutations at the agouti locus in mice, induced by retrotransposon-like intracisternal A particles, result in ectopic over-expression of ASP and animals with much higher proportions of all-yellow hairs. This abnormal presence of ASP in essentially all body cells results in the 'yellow agouti obese mouse syndrome.' The obesity has been associated with binding of ASP to melanocortin receptor 4 inactivating the latter. The syndrome also includes hyperinsulinemia, increased somatic growth, and increased susceptibility to hyperplasia and carcinogenesis. The physiologic and molecular bases for these syndrome components have not yet been elucidated. This historically orientated review is subdivided, where applicable, into pre- and post-1992 subsections to emphasize the impact of the cloning of the agouti and extension loci and their protein products on the identification of the molecular and physiological pathways modulating the manifold aspects of pheomelanogenesis.
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Affiliation(s)
- George L Wolff
- Division of Biochemical Toxicology, National Center for Toxicological Research/US Food and Drug Administration, Jefferson, AR 72079, USA.
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Scott MC, Suzuki I, Abdel-Malek ZA. Regulation of the human melanocortin 1 receptor expression in epidermal melanocytes by paracrine and endocrine factors and by ultraviolet radiation. PIGMENT CELL RESEARCH 2002; 15:433-9. [PMID: 12453185 DOI: 10.1034/j.1600-0749.2002.02051.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of this study is to investigate the regulation of the human melanocortin 1 receptor (MC1R) expression in cultured normal human melanocytes (NHM) by specific paracrine and endocrine factors, and by ultraviolet radiation (UVR). Treatment of NHM with alpha-melanotropin [alpha-melanocyte stimulating hormone (alpha-MSH)] increased MC1R mRNA level; the response was often more pronounced in NHM with a low (NHM-c) than in NHM with a high melanin content (NHM-b). Endothelin-1 increased MC1R mRNA level in NHM regardless of their melanin content. Basic fibroblast growth factor consistently up regulated MC1R mRNA level in NHM-b but not in NHM-c. Activation of protein kinase C by 12-0-tetradecanoylphorbol-13-acetate slightly increased, while stimulation of adenylate cyclase by forskolin markedly up-regulated the MC1R mRNA level. beta-Estradiol increased, and combined treatment with beta-estradiol and alpha-MSH further elevated, MC1R mRNA level in NHM-c and NHM-b. Testosterone reduced, while progesterone had no effect on, MC1R mRNA level. Agouti signaling protein reduced, and UVR down regulated dose-dependently MC1R mRNA level in NHM-b and NHM-c. This effect was reversed 24 h after irradiation with the lower doses of 7 or 14 mJ/cm2, but not after exposure to a higher, more cytotoxic dose of UVR. We conclude that the MC1R is regulated by paracrine factors, including its own ligands, by specific endocrine sex hormones, and by UVR. Differences in the responses of NHM to some of these factors suggest differential regulation of MC1R gene expression, which may contribute to the variation in constitutive and UV-induced cutaneous pigmentation in humans.
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Affiliation(s)
- M Cathy Scott
- Department of Dermatology, University of Cincinnati, Cincinnati, Ohio 45267-592, USA
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Abstract
The agouti protein regulates pigmentation in the mouse hair follicle producing a black hair with a subapical yellow band. Its effect on pigmentation is achieved by antagonizing the binding of alpha-melanocyte stimulating hormone (alpha-MSH) to melanocortin 1 receptor (Mc1r), switching melanin synthesis from eumelanin (black/brown) to phaeomelanin (red/yellow). Dominant mutations in the non-coding region of mouse agouti cause yellow coat colour and ectopic expression also results in obesity, type 11 diabetes, increased somatic growth and tumourigenesis. At least some of these pleiotropic effects can be explained by antagonism of other members of the melanocortin receptor family by agouti protein. The yellow coat colour is the result of agouti chronically antagonizing the binding of alpha-MSH to Mc1r and the obese phenotype results from agouti protein antagonizing the binding of alpha-MSH to Mc3r and/or Mc4r. Despite the existence of a highly homologous agouti protein in humans, agouti signal protein (ASIP), its role has yet to be defined. However it is known that human ASIP is expressed at highest levels in adipose tissue where it may antagonize one of the melanocortin receptors. The conserved nature of the agouti protein combined with the diverse phenotypic effects of agouti mutations in mouse and the different expression patterns of human and mouse agouti, suggest ASIP may play a role in human energy homeostasis and possibly human pigmentation.
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Affiliation(s)
- Joanne Voisey
- Co-operative Research Centre for Diagnostics, Queensland University of Technology, Brisbane, Australia
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Sviderskaya EV, Hill SP, Balachandar D, Barsh GS, Bennett DC. Agouti signaling protein and other factors modulating differentiation and proliferation of immortal melanoblasts. Dev Dyn 2001; 221:373-9. [PMID: 11500974 DOI: 10.1002/dvdy.1153] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The melanocyte lineage potentially forms an attractive model system for studies in cell differentiation, developmental genetics, cell signaling, and melanoma, because differentiated cells produce the visible pigment melanin. Immortal lines of murine melanoblasts (melanocyte precursors) have been described previously, but induction of differentiation involved a complex culture system with keratinocyte feeder cells. Here we describe conditions for both growth and induced differentiation of the melanoblast line melb-a, without feeder cells, and analyze factors that directly control proliferation and differentiation of these pure melanoblasts. Several active factors are products of developmental and other coat color genes, including stem cell factor (SCF), melanocyte-stimulating hormone (alphaMSH), and agouti signaling protein (ASP), a natural antagonist at the MSH receptor (melanocortin 1 receptor, MC1R) encoded by the agouti gene. A stable analog of alphaMSH (NDP-MSH) stimulated differentiation and inhibited growth. ASP in excess inhibited both effects of NDP-MSH, that is, ASP could inhibit pigmentation and stimulate growth. These effects provide an explanation for the interactions in mice of melanocyte developmental mutations with yellow agouti and Mc1r alleles, and a role for embryonic expression patterns of ASP.
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Affiliation(s)
- E V Sviderskaya
- Department of Anatomy and Developmental Biology, St George's Hospital Medical School, London, United Kingdom.
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