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Slominski RM, Kim TK, Janjetovic Z, Brożyna AA, Podgorska E, Dixon KM, Mason RS, Tuckey RC, Sharma R, Crossman DK, Elmets C, Raman C, Jetten AM, Indra AK, Slominski AT. Malignant Melanoma: An Overview, New Perspectives, and Vitamin D Signaling. Cancers (Basel) 2024; 16:2262. [PMID: 38927967 PMCID: PMC11201527 DOI: 10.3390/cancers16122262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2024] [Revised: 06/09/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024] Open
Abstract
Melanoma, originating through malignant transformation of melanin-producing melanocytes, is a formidable malignancy, characterized by local invasiveness, recurrence, early metastasis, resistance to therapy, and a high mortality rate. This review discusses etiologic and risk factors for melanoma, diagnostic and prognostic tools, including recent advances in molecular biology, omics, and bioinformatics, and provides an overview of its therapy. Since the incidence of melanoma is rising and mortality remains unacceptably high, we discuss its inherent properties, including melanogenesis, that make this disease resilient to treatment and propose to use AI to solve the above complex and multidimensional problems. We provide an overview on vitamin D and its anticancerogenic properties, and report recent advances in this field that can provide solutions for the prevention and/or therapy of melanoma. Experimental papers and clinicopathological studies on the role of vitamin D status and signaling pathways initiated by its active metabolites in melanoma prognosis and therapy are reviewed. We conclude that vitamin D signaling, defined by specific nuclear receptors and selective activation by specific vitamin D hydroxyderivatives, can provide a benefit for new or existing therapeutic approaches. We propose to target vitamin D signaling with the use of computational biology and AI tools to provide a solution to the melanoma problem.
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Affiliation(s)
- Radomir M. Slominski
- Department of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA;
| | - Tae-Kang Kim
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
| | - Zorica Janjetovic
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
| | - Anna A. Brożyna
- Department of Human Biology, Institute of Biology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, 87-100 Torun, Poland;
| | - Ewa Podgorska
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
| | - Katie M. Dixon
- School of Medical Sciences, The University of Sydney, Sydney, NSW 2050, Australia; (K.M.D.); (R.S.M.)
| | - Rebecca S. Mason
- School of Medical Sciences, The University of Sydney, Sydney, NSW 2050, Australia; (K.M.D.); (R.S.M.)
| | - Robert C. Tuckey
- School of Molecular Sciences, University of Western Australia, Perth, WA 6009, Australia;
| | - Rahul Sharma
- Department of Biomedical Informatics and Data Science, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA;
| | - David K. Crossman
- Department of Genetics and Bioinformatics, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA;
| | - Craig Elmets
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
| | - Chander Raman
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
| | - Anton M. Jetten
- Cell Biology Section, NIEHS—National Institutes of Health, Research Triangle Park, NC 27709, USA;
| | - Arup K. Indra
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97331, USA
- Department of Dermatology, Oregon Health & Science University, Portland, OR 97239, USA
- Knight Cancer Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Andrzej T. Slominski
- Department of Dermatology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (T.-K.K.); (Z.J.); (E.P.); (C.E.); (C.R.)
- Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Pathology and Laboratory Medicine Service, Veteran Administration Medical Center, Birmingham, AL 35233, USA
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2
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Kim HJ, Kim YH. Molecular Frontiers in Melanoma: Pathogenesis, Diagnosis, and Therapeutic Advances. Int J Mol Sci 2024; 25:2984. [PMID: 38474231 DOI: 10.3390/ijms25052984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 03/01/2024] [Accepted: 03/02/2024] [Indexed: 03/14/2024] Open
Abstract
Melanoma, a highly aggressive skin cancer, is characterized by rapid progression and high mortality. Recent advances in molecular pathogenesis have shed light on genetic and epigenetic changes that drive melanoma development. This review provides an overview of these developments, focusing on molecular mechanisms in melanoma genesis. It highlights how mutations, particularly in the BRAF, NRAS, c-KIT, and GNAQ/GNA11 genes, affect critical signaling pathways. The evolution of diagnostic techniques, such as genomics, transcriptomics, liquid biopsies, and molecular biomarkers for early detection and prognosis, is also discussed. The therapeutic landscape has transformed with targeted therapies and immunotherapies, improving patient outcomes. This paper examines the efficacy, challenges, and prospects of these treatments, including recent clinical trials and emerging strategies. The potential of novel treatment strategies, including neoantigen vaccines, adoptive cell transfer, microbiome interactions, and nanoparticle-based combination therapy, is explored. These advances emphasize the challenges of therapy resistance and the importance of personalized medicine. This review underlines the necessity for evidence-based therapy selection in managing the increasing global incidence of melanoma.
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Affiliation(s)
- Hyun Jee Kim
- Department of Dermatology, International St. Mary's Hospital, College of Medicine, Catholic Kwandong University, Incheon 22711, Republic of Korea
| | - Yeong Ho Kim
- Department of Dermatology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
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Ghazi M, Khanna S, Subramaniam Y, Rengaraju J, Sultan F, Gupta I, Sharma K, Chandna S, Gokhale RS, Natarajan V. Sustained pigmentation causes DNA damage and invokes translesion polymerase Polκ for repair in melanocytes. Nucleic Acids Res 2023; 51:10451-10466. [PMID: 37697436 PMCID: PMC10602914 DOI: 10.1093/nar/gkad704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 08/02/2023] [Accepted: 08/14/2023] [Indexed: 09/13/2023] Open
Abstract
Melanin protects skin cells from ultraviolet radiation-induced DNA damage. However, intermediates of eumelanin are highly reactive quinones that are potentially genotoxic. In this study, we systematically investigate the effect of sustained elevation of melanogenesis and map the consequent cellular repair response of melanocytes. Pigmentation increases γH2AX foci, DNA abasic sites, causes replication stress and invokes translesion polymerase Polκ in primary human melanocytes, as well as mouse melanoma cells. Confirming the causal link, CRISPR-based genetic ablation of tyrosinase results in depigmented cells with low Polκ levels. During pigmentation, Polκ activates replication stress response and keeps a check on uncontrolled proliferation of cells harboring melanin-damaged DNA. The mutational landscape observed in human melanoma could in part explain the error-prone bypass of DNA lesions by Polκ, whose absence would lead to genome instability. Thereby, translesion polymerase Polκ is a critical response of pigmenting melanocytes to combat melanin-induced DNA alterations. Our study illuminates the dark side of melanin and identifies (eu)melanogenesis as a key missing link between tanning response and mutagenesis, mediated via the necessary evil translesion polymerase, Polκ.
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Affiliation(s)
- Madeeha Ghazi
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Shivangi Khanna
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Yogaspoorthi Subramaniam
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Jeyashri Rengaraju
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Farina Sultan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Iti Gupta
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
| | - Kanupriya Sharma
- Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Delhi 110054, India
| | - Sudhir Chandna
- Institute of Nuclear Medicine and Allied Sciences, Defence Research and Development Organization, Delhi 110054, India
| | - Rajesh S Gokhale
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Vivek T Natarajan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi 110025, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
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Zhang X, Zhu J, Zhang J, Zhao H. Melanocyte stem cells and hair graying. J Cosmet Dermatol 2023; 22:1720-1723. [PMID: 36853923 DOI: 10.1111/jocd.15652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/27/2022] [Accepted: 01/13/2023] [Indexed: 03/01/2023]
Abstract
OBJECTIVES To explore the relationship between melanocyte stem cells in the hair follicle bulge and hair graying so as to fully understand their key role in the pathogenesis of hair graying. METHODS The published articles about "hair graying, hair color, pigmentation disorders" and "melanocyte stem cells, melanocyte" were searched and analyzed in PubMed to explore their relationship. RESULTS Melanocytes in hair bulb are involved in the pathogenesis of hair graying as well as the melanocyte stem cells in hair follicle bulge also play important roles in the formation of hair graying through some ways. CONCLUSION Loss of melanocyte stem cells in hair follicle bulge is one of the main reasons of hair graying, and more researches are needed to explain the underlying mechanisms of ectopic differentiation of melanocyte stem cells in different individual.
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Affiliation(s)
- Xiaojiao Zhang
- Department of Dermatology, University-Town Hospital of Chongqing Medical University, Chongqing, China
| | - Jinyu Zhu
- Department of Dermatology, University-Town Hospital of Chongqing Medical University, Chongqing, China
| | - Jiezhi Zhang
- Department of Dermatology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hengguang Zhao
- Department of Dermatology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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5
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Waku T, Nakada S, Masuda H, Sumi H, Wada A, Hirose S, Aketa I, Kobayashi A. The CNC-family transcription factor Nrf3 coordinates the melanogenesis cascade through macropinocytosis and autophagy regulation. Cell Rep 2023; 42:111906. [PMID: 36640303 DOI: 10.1016/j.celrep.2022.111906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 10/06/2022] [Accepted: 12/09/2022] [Indexed: 12/31/2022] Open
Abstract
Melanin is a pigment produced from the amino acid L-tyrosine in melanosomes. The CNC-family transcription factor Nrf3 is expressed in the basal layer of the epidermis, where melanocytes reside, but its melanogenic function is unclear. Here, we show that Nrf3 regulates macropinocytosis and autophagy to coordinate melanogenesis cascade. In response to an exogenous inducer of melanin production, forskolin, Nrf3 upregulates the core melanogenic gene circuit, which includes Mitf, Tyr, Tyrp1, Pmel, and Oca2. Furthermore, Nrf3 induces the gene expression of Cln3, an autophagosome-related factor, for melanin precursor uptake by macropinocytosis. Ulk2 and Gabarapl2 are also identified as Nrf3-target autophagosome-related genes for melanosome formation. In parallel, Nrf3 prompts autolysosomal melanosome degradation for melanocyte survival. An endogenous melanogenic inducer αMSH also activates Nrf3-mediated melanin production, whereas it is suppressed by an HIV-1 protease inhibitor, nelfinavir. These findings indicate the significant role of Nrf3 in the melanogenesis and the anti-melanogenic potential of nelfinavir.
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Affiliation(s)
- Tsuyoshi Waku
- Laboratory for Genetic Code, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan.
| | - Sota Nakada
- Laboratory for Genetic Code, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Haruka Masuda
- Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Haruna Sumi
- Laboratory for Genetic Code, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Ayaka Wada
- Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Shuuhei Hirose
- Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Iori Aketa
- Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
| | - Akira Kobayashi
- Laboratory for Genetic Code, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan; Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan.
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6
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Dolinska MB, Woods T, Osuna I, Sergeev YV. Protein Biochemistry and Molecular Modeling of the Intra-Melanosomal Domain of Human Recombinant Tyrp2 Protein and OCA8-Related Mutant Variants. Int J Mol Sci 2022; 23:ijms23031305. [PMID: 35163231 PMCID: PMC8836267 DOI: 10.3390/ijms23031305] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/14/2022] [Accepted: 01/20/2022] [Indexed: 12/27/2022] Open
Abstract
Tyrosinase-related protein 2 (Tyrp2) is involved in the melanogenesis pathway, catalyzing the tautomerization of dopachrome to 5,6-dihydroxyindole-2-carboxylic acid (DHICA). Recently, a new type of albinism was discovered with disease-causing mutations in the TYRP2 gene. Here, for the first time, we characterized the intra-melanosomal protein domain of Tyrp2 (residues 1-474) and missense variants C40S and C61W, which mimic the alterations found in genetic studies. Recombinant proteins were produced in the Trichoplusia Ni (Ti. Ni) larvae, purified by a combination of immobilized metal affinity (IMAC) and gel-filtration (GF) chromatography, and biochemically characterized. The mutants showed the protein expression in the lysates such as the wild type; however, undetectable protein yield after two steps of purification exhibited their misfolding and instability. In addition, the misfolding effect of the mutations was confirmed computationally using homology modeling and molecular docking. Together, experiments in vitro and computer simulations indicated the critical role of the Cys-rich domain in the Tyrp2 protein stability. The results are consistent with molecular modeling, global computational mutagenesis, and clinical data, proving the significance of genetic alterations in cysteine residues, which could cause oculocutaneous albinism type 8.
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Slominski RM, Sarna T, Płonka PM, Raman C, Brożyna AA, Slominski AT. Melanoma, Melanin, and Melanogenesis: The Yin and Yang Relationship. Front Oncol 2022; 12:842496. [PMID: 35359389 PMCID: PMC8963986 DOI: 10.3389/fonc.2022.842496] [Citation(s) in RCA: 119] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 01/24/2022] [Indexed: 12/22/2022] Open
Abstract
Melanin pigment plays a critical role in the protection against the harmful effects of ultraviolet radiation and other environmental stressors. It is produced by the enzymatic transformation of L-tyrosine to dopaquinone and subsequent chemical and biochemical reactions resulting in the formation of various 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI) oligomers-main constituents of eumelanin, and benzothiazine and benzothiazole units of pheomelanin. The biosynthesis of melanin is regulated by sun exposure and by many hormonal factors at the tissue, cellular, and subcellular levels. While the presence of melanin protects against the development of skin cancers including cutaneous melanoma, its presence may be necessary for the malignant transformation of melanocytes. This shows a complex role of melanogenesis in melanoma development defined by chemical properties of melanin and the nature of generating pathways such as eu- and pheomelanogenesis. While eumelanin is believed to provide radioprotection and photoprotection by acting as an efficient antioxidant and sunscreen, pheomelanin, being less photostable, can generate mutagenic environment after exposure to the short-wavelength UVR. Melanogenesis by itself and its highly reactive intermediates show cytotoxic, genotoxic, and mutagenic activities, and it can stimulate glycolysis and hypoxia-inducible factor 1-alpha (HIF-1α) activation, which, combined with their immunosuppressive effects, can lead to melanoma progression and resistance to immunotherapy. On the other hand, melanogenesis-related proteins can be a target for immunotherapy. Interestingly, clinicopathological analyses on advanced melanomas have shown a negative correlation between tumor pigmentation and diseases outcome as defined by overall survival and disease-free time. This indicates a "Yin and Yang" role for melanin and active melanogenesis in melanoma development, progression, and therapy. Furthermore, based on the clinical, experimental data and diverse effects of melanogenesis, we propose that inhibition of melanogenesis in advanced melanotic melanoma represents a realistic adjuvant strategy to enhance immuno-, radio-, and chemotherapy.
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Affiliation(s)
- Radomir M Slominski
- Graduate Biomedical Sciences Program, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Przemysław M Płonka
- Department of Biophysics and Cancer Biology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Chander Raman
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Anna A Brożyna
- Department of Human Biology, Institute of Biology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Toruń, Poland
| | - Andrzej T Slominski
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, United States.,Pathology Laboratory Service, Veteran Administration Medical Center at Birmingham, Birmingham, AL, United States
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8
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Skoniecka A, Cichorek M, Tyminska A, Pelikant-Malecka I, Dziewiatkowski J. Melanization as unfavorable factor in amelanotic melanoma cell biology. PROTOPLASMA 2021; 258:935-948. [PMID: 33506271 PMCID: PMC8433105 DOI: 10.1007/s00709-021-01613-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 01/15/2021] [Indexed: 05/15/2023]
Abstract
The biology of three amelanotic melanoma cell lines (Ab, B16F10, and A375) of different species origin was analyzed during in vitro induced melanization in these cells. Melanin production was induced by DMEM medium characterized by a high level of L-tyrosine (a basic amino acid for melanogenesis). The biodiversity of amelanotic melanoma cells was confirmed by their different responses to melanogenesis induction; Ab hamster melanomas underwent intensive melanization, mouse B16F10 darkened slightly, while human A375 cells did not show any change in melanin content. Highly melanized Ab cells entered a cell death pathway, while slight melanization did not influence cell biology in a significant way. The rapid and high melanization of Ab cells induced apoptosis documented by phosphatidylserine externalization, caspase activation, and mitochondrial energetic state decrease. Melanoma cell type, culture medium, and time of incubation should be taken into consideration during amelanotic melanoma cell culture in vitro. L-tyrosine, as a concentration-dependent factor presented in the culture media, could stimulate some amelanotic melanoma cell lines (Ab, B16F10) to melanin production. The presence of melanin should be considered in the examination of antimelanoma compounds in vitro, because induction of melanin may interfere or be helpful in the treatment of amelanotic melanoma.
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Affiliation(s)
- A. Skoniecka
- Embryology Department, Medical University of Gdansk, Ul. Debinki 1 St, 80-211, Gdansk, Poland
| | - M. Cichorek
- Embryology Department, Medical University of Gdansk, Ul. Debinki 1 St, 80-211, Gdansk, Poland
| | - A. Tyminska
- Embryology Department, Medical University of Gdansk, Ul. Debinki 1 St, 80-211, Gdansk, Poland
| | - I. Pelikant-Malecka
- Department of Medical Laboratory Diagnostics-Biobank, Medical University of Gdansk, 80-211 Gdansk, Poland
- Biobanking and Biomolecular Resources Research Infrastructure Poland (BBMRI.PL), 80-211 Gdansk, Poland
| | - J. Dziewiatkowski
- Department of Anatomy and Neurobiology, Medical University of Gdansk, Debinki 1 St, 80-211, Gdansk, Poland
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Identification of critical amino acid residues in the regulatory N-terminal domain of PMEL. Sci Rep 2021; 11:7730. [PMID: 33833328 PMCID: PMC8032716 DOI: 10.1038/s41598-021-87259-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 03/26/2021] [Indexed: 01/22/2023] Open
Abstract
The pigment cell-specific protein PMEL forms a functional amyloid matrix in melanosomes onto which the pigment melanin is deposited. The amyloid core consists of a short proteolytic fragment, which we have termed the core-amyloid fragment (CAF) and perhaps additional parts of the protein, such as the PKD domain. A highly O-glycosylated repeat (RPT) domain also derived from PMEL proteolysis associates with the amyloid and is necessary to establish the sheet-like morphology of the assemblies. Excluded from the aggregate is the regulatory N-terminus, which nevertheless must be linked in cis to the CAF in order to drive amyloid formation. The domain is then likely cleaved away immediately before, during, or immediately after the incorporation of a new CAF subunit into the nascent amyloid. We had previously identified a 21 amino acid long region, which mediates the regulatory activity of the N-terminus towards the CAF. However, many mutations in the respective segment caused misfolding and/or blocked PMEL export from the endoplasmic reticulum, leaving their phenotype hard to interpret. Here, we employ a saturating mutagenesis approach targeting the motif at single amino acid resolution. Our results confirm the critical nature of the PMEL N-terminal region and identify several residues essential for PMEL amyloidogenesis.
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10
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Functional Mammalian Amyloids and Amyloid-Like Proteins. Life (Basel) 2020; 10:life10090156. [PMID: 32825636 PMCID: PMC7555005 DOI: 10.3390/life10090156] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/12/2020] [Accepted: 08/19/2020] [Indexed: 02/06/2023] Open
Abstract
Amyloids are highly ordered fibrous cross-β protein aggregates that are notorious primarily because of association with a variety of incurable human and animal diseases (termed amyloidoses), including Alzheimer’s disease (AD), Parkinson’s disease (PD), type 2 diabetes (T2D), and prion diseases. Some amyloid-associated diseases, in particular T2D and AD, are widespread and affect hundreds of millions of people all over the world. However, recently it has become evident that many amyloids, termed “functional amyloids,” are involved in various activities that are beneficial to organisms. Functional amyloids were discovered in diverse taxa, ranging from bacteria to mammals. These amyloids are involved in vital biological functions such as long-term memory, storage of peptide hormones and scaffolding melanin polymerization in animals, substrate attachment, and biofilm formation in bacteria and fungi, etc. Thus, amyloids undoubtedly are playing important roles in biological and pathological processes. This review is focused on functional amyloids in mammals and summarizes approaches used for identifying new potentially amyloidogenic proteins and domains.
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Avni A, Swasthi HM, Majumdar A, Mukhopadhyay S. Intrinsically disordered proteins in the formation of functional amyloids from bacteria to humans. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 166:109-143. [PMID: 31521230 DOI: 10.1016/bs.pmbts.2019.05.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Amyloids are nanoscopic ordered self-assemblies of misfolded proteins that are formed via aggregation of partially unfolded or intrinsically disordered proteins (IDPs) and are commonly linked to devastating human diseases. An enlarging body of recent research has demonstrated that certain amyloids can be beneficial and participate in a wide range of physiological functions from bacteria to humans. These amyloids are termed as functional amyloids. Like disease-associated amyloids, a vast majority of functional amyloids are derived from a range of IDPs or hybrid proteins containing ordered domains and intrinsically disordered regions (IDRs). In this chapter, we describe an account of recent studies on the aggregation behavior of IDPs resulting in the formation of functional amyloids in a diverse range of organisms from bacteria to human. We also discuss the strategies that are used by these organisms to regulate the spatiotemporal amyloid assembly in their physiological functions.
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Affiliation(s)
- Anamika Avni
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, and Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Hema M Swasthi
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, and Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Anupa Majumdar
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, and Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India
| | - Samrat Mukhopadhyay
- Centre for Protein Science, Design and Engineering, Department of Biological Sciences, and Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Punjab, India.
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12
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Semidominant GPNMB Mutations in Amyloidosis Cutis Dyschromica. J Invest Dermatol 2019; 139:2550-2554.e9. [PMID: 31226264 DOI: 10.1016/j.jid.2019.05.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 11/20/2022]
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13
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Graham M, Tzika AC, Mitchell SM, Liu X, Leonhardt RM. Repeat domain-associated O-glycans govern PMEL fibrillar sheet architecture. Sci Rep 2019; 9:6101. [PMID: 30988362 PMCID: PMC6465243 DOI: 10.1038/s41598-019-42571-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 02/06/2019] [Indexed: 12/20/2022] Open
Abstract
PMEL is a pigment cell-specific protein that forms a functional amyloid matrix in melanosomes. The matrix consists of well-separated fibrillar sheets on which the pigment melanin is deposited. Using electron tomography, we demonstrate that this sheet architecture is governed by the PMEL repeat (RPT) domain, which associates with the amyloid as an accessory proteolytic fragment. Thus, the RPT domain is dispensable for amyloid formation as such but shapes the morphology of the matrix, probably in order to maximize the surface area available for pigment adsorption. Although the primary amino acid sequence of the RPT domain differs vastly among various vertebrates, we show that it is a functionally conserved, interchangeable module. RPT domains of all species are predicted to be very highly O-glycosylated, which is likely the common defining feature of this domain. O-glycosylation is indeed essential for RPT domain function and the establishment of the PMEL sheet architecture. Thus, O-glycosylation, not amino acid sequence, appears to be the major factor governing the characteristic PMEL amyloid morphology.
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Affiliation(s)
- Morven Graham
- Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06519, USA
| | - Athanasia C Tzika
- Department of Genetics & Evolution, Laboratory of Artificial & Natural Evolution (LANE), Sciences III Building, 1211, Geneva, 4, Switzerland
| | - Susan M Mitchell
- Department of Immunobiology, Yale University School of Medicine, 300 Cedar Street, New Haven, CT, 06519, USA
| | - Xinran Liu
- Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06519, USA
| | - Ralf M Leonhardt
- Department of Immunobiology, Yale University School of Medicine, 300 Cedar Street, New Haven, CT, 06519, USA.
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14
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Wei Z, Xu C, Liu S, Song F, Liu Z, Qu X. Metabonomics study of the effects of traditional Chinese medicine formula Ermiaowan on hyperuricemic rats. J Sep Sci 2017; 41:560-570. [DOI: 10.1002/jssc.201700985] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/29/2017] [Accepted: 10/23/2017] [Indexed: 01/04/2023]
Affiliation(s)
- Zhongbao Wei
- Pharmacology of Chinese Traditional Medicine; College of Pharmacy; Changchun University of Chinese Medicine; Changchun P. R.China
| | - Chen Xu
- School of Chemical Engineering; Changchun University of Technology; Changchun P. R. China
| | - Shu Liu
- National Center of Mass Spectrometry in Changchun & Jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry; Changchun Institute of Applied Chemistry; Chinese Academy of Sciences; Changchun P. R. China
| | - Fengrui Song
- National Center of Mass Spectrometry in Changchun & Jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry; Changchun Institute of Applied Chemistry; Chinese Academy of Sciences; Changchun P. R. China
| | - Zhiqiang Liu
- National Center of Mass Spectrometry in Changchun & Jilin Province Key Laboratory of Chinese Medicine Chemistry and Mass Spectrometry; Changchun Institute of Applied Chemistry; Chinese Academy of Sciences; Changchun P. R. China
| | - Xiaobo Qu
- Pharmacology of Chinese Traditional Medicine; College of Pharmacy; Changchun University of Chinese Medicine; Changchun P. R.China
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15
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Scognamiglio F, Travan A, Turco G, Borgogna M, Marsich E, Pasqua M, Paoletti S, Donati I. Adhesive coatings based on melanin-like nanoparticles for surgical membranes. Colloids Surf B Biointerfaces 2017; 155:553-559. [PMID: 28499217 DOI: 10.1016/j.colsurfb.2017.04.057] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/24/2017] [Accepted: 04/28/2017] [Indexed: 02/06/2023]
Abstract
Adhesive coatings for implantable biomaterials can be designed to prevent material displacement from the site of implant. In this paper, a strategy based on the use of melanin-like nanoparticles (MNPs) for the development of adhesive coatings for polysaccharidic membranes was devised. MNPs were synthesized in vitro and characterized in terms of dimensions and surface potential, as a function of pH and ionic strength. The in vitro biocompatibility of MNPs was investigated on fibroblast cells, while the antimicrobial properties of MNPs in suspension were evaluated on E. coli and S. aureus cultures. The manufacturing of the adhesive coatings was carried out by spreading MNPs over the surface of polysaccharidic membranes; the adhesive properties of the nano-engineered coating to the target tissue (intestinal serosa) were studied in simulated physiological conditions. Overall, this study opens for novel approaches in the design of naturally inspired nanostructured adhesive systems.
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Affiliation(s)
- Francesca Scognamiglio
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy.
| | - Andrea Travan
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy
| | - Gianluca Turco
- Department of Medical, Surgical and Health Sciences, University of Trieste, Piazza dell'Ospitale 1, I-34129 Trieste, Italy
| | - Massimiliano Borgogna
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy
| | - Eleonora Marsich
- Department of Medical, Surgical and Health Sciences, University of Trieste, Piazza dell'Ospitale 1, I-34129 Trieste, Italy
| | - Mattia Pasqua
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy
| | - Sergio Paoletti
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy
| | - Ivan Donati
- Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, I-34127, Trieste, Italy
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16
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Piacenti-Silva M, Matos AA, Paulin JV, Alavarce RADS, de Oliveira RC, Graeff CFO. Biocompatibility investigations of synthetic melanin and melanin analogue for application in bioelectronics. POLYM INT 2016. [DOI: 10.1002/pi.5192] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Marina Piacenti-Silva
- DF-FC, UNESP - Universidade Estadual Paulista; Av. Eng. Luiz Edmundo Carrijo Coube 14-01 17033-360 Bauru SP Brazil
| | - Adriana Arruda Matos
- USP Campus Bauru - Universidade de São Paulo; Alameda Dr Octávio Pinheiro Brisolla 9-75 17012-901 Bauru SP Brazil
| | - João Vitor Paulin
- UNESP - Universidade Estadual Paulista; POSMAT - Programa de Pós-Graduação em Ciência e Tecnologia de Materiais; Av. Eng. Luiz Edmundo Carrijo Coube 14-01 Bauru SP Brazil
| | | | - Rodrigo Cardoso de Oliveira
- USP Campus Bauru - Universidade de São Paulo; Alameda Dr Octávio Pinheiro Brisolla 9-75 17012-901 Bauru SP Brazil
| | - Carlos FO Graeff
- DF-FC, UNESP - Universidade Estadual Paulista; Av. Eng. Luiz Edmundo Carrijo Coube 14-01 17033-360 Bauru SP Brazil
- UNESP - Universidade Estadual Paulista; POSMAT - Programa de Pós-Graduação em Ciência e Tecnologia de Materiais; Av. Eng. Luiz Edmundo Carrijo Coube 14-01 Bauru SP Brazil
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17
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Heiduschka P, Blitgen-Heinecke P, Tura A, Kokkinou D, Julien S, Hofmeister S, Bartz-Schmidt KU, Schraermeyer U. Melanin Precursor 5,6-Dihydroxyindol: Protective Effects and Cytotoxicity on Retinal Cells in vitro and in vivo. Toxicol Pathol 2016; 35:1030-8. [DOI: 10.1080/01926230701831358] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
5,6-Dihydroxyindole (DHI) is a melanin pigment precursor with antioxidant properties. In the light of a report about cytotoxicity of DHI, the aim of this study was to assess possible toxic effects of DHI on cells related to the eye, such as human ARPE-19 cells and mouse retinal explants. Moreover, DHI was tested on its effects on retinal function in vivo using electroretinography. We found cytotoxicity of DHI against ARPE-19 cells at 100 μM, but not at 10 μM. 10 μM DHI exhibited a slight, though not significant protective activity against UV-A damage in ARPE-19 cells. We found cytoprotection in cultured mouse retinas by 50 μM DHI or its diacetylated derivative 5,6-diacetoxyindole (DAI), respectively. In ERG measurements in vivo, amplitudes were decreased only slightly by 100 μM DHI compared to saline, whereas a better preservation of amplitudes was visible at 10 μM DHI, in particular with respect to cones. In histological sections, more cones were found at 10 μM DHI than at 100 μM DHI. As a conclusion, DHI shows a slight protective effect at 10 μM both in vitro and in vivo. At 100 μM, it shows a strong cytotoxicity in vitro, which is strongly reduced in vivo.
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Affiliation(s)
- Peter Heiduschka
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
- Steinbeis Transfer Centre for Pathology and Toxicology of the Eye, Schleichstr. 12/1, D-72076 Tübingen, Germany
| | - Petra Blitgen-Heinecke
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
- Steinbeis Transfer Centre for Pathology and Toxicology of the Eye, Schleichstr. 12/1, D-72076 Tübingen, Germany
| | - Aysegül Tura
- University Eye Hospital Dept. I, Schleichstr. 12, D-72076 Tübingen, Germany
| | - Despina Kokkinou
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
| | - Sylvie Julien
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
| | - Sabine Hofmeister
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
| | | | - Ulrich Schraermeyer
- Section for Experimental Vitreoretinal Surgery, University Eye Hospital Tübingen, Schleichstr. 12/1, D-72076 Tübingen, Germany
- Steinbeis Transfer Centre for Pathology and Toxicology of the Eye, Schleichstr. 12/1, D-72076 Tübingen, Germany
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18
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Kirscher L, Deán-Ben XL, Scadeng M, Zaremba A, Zhang Q, Kober C, Fehm TF, Razansky D, Ntziachristos V, Stritzker J, Szalay AA. Doxycycline Inducible Melanogenic Vaccinia Virus as Theranostic Anti-Cancer Agent. Theranostics 2015; 5:1045-57. [PMID: 26199644 PMCID: PMC4508495 DOI: 10.7150/thno.12533] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 05/14/2015] [Indexed: 12/02/2022] Open
Abstract
We reported earlier the diagnostic potential of a melanogenic vaccinia virus based system in magnetic resonance (MRI) and optoacoustic deep tissue imaging (MSOT). Since melanin overproduction lead to attenuated virus replication, we constructed a novel recombinant vaccinia virus strain (rVACV), GLV-1h462, which expressed the key enzyme of melanogenesis (tyrosinase) under the control of an inducible promoter-system. In this study melanin production was detected after exogenous addition of doxycycline in two different tumor xenograft mouse models. Furthermore, it was confirmed that this novel vaccinia virus strain still facilitated signal enhancement as detected by MRI and optoacoustic tomography. At the same time we demonstrated an enhanced oncolytic potential compared to the constitutively melanin synthesizing rVACV system.
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Affiliation(s)
- Lorenz Kirscher
- 1. University of Würzburg, Department of Biochemistry, Am Hubland, 97074 Würzburg, Germany
| | - Xosé Luis Deán-Ben
- 4. Helmholtz Institute, IBMI, Ingolstädter Landstraße 1, 85764 Oberschleißheim, Germany
| | - Miriam Scadeng
- 3. University of San Diego, Center of Functional MRI, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Angelika Zaremba
- 4. Helmholtz Institute, IBMI, Ingolstädter Landstraße 1, 85764 Oberschleißheim, Germany
| | - Qian Zhang
- 2. Genelux Cooperation, San Diego Science Center, 3030 Bunker Hill St, San Diego, CA 92109, USA
| | - Christina Kober
- 1. University of Würzburg, Department of Biochemistry, Am Hubland, 97074 Würzburg, Germany
| | - Thomas Felix Fehm
- 4. Helmholtz Institute, IBMI, Ingolstädter Landstraße 1, 85764 Oberschleißheim, Germany
| | - Daniel Razansky
- 4. Helmholtz Institute, IBMI, Ingolstädter Landstraße 1, 85764 Oberschleißheim, Germany
| | - Vasilis Ntziachristos
- 4. Helmholtz Institute, IBMI, Ingolstädter Landstraße 1, 85764 Oberschleißheim, Germany
| | - Jochen Stritzker
- 1. University of Würzburg, Department of Biochemistry, Am Hubland, 97074 Würzburg, Germany
- 2. Genelux Cooperation, San Diego Science Center, 3030 Bunker Hill St, San Diego, CA 92109, USA
| | - Aladar A. Szalay
- 1. University of Würzburg, Department of Biochemistry, Am Hubland, 97074 Würzburg, Germany
- 2. Genelux Cooperation, San Diego Science Center, 3030 Bunker Hill St, San Diego, CA 92109, USA
- 5. Department of Radiation Oncology, Moores Cancer Center, University of California, La Jolla, CA 92093, USA
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19
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Ho CC, Ding SJ. Novel SiO2/PDA hybrid coatings to promote osteoblast-like cell expression on titanium implants. J Mater Chem B 2015; 3:2698-2707. [DOI: 10.1039/c4tb01841a] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A facile preparation route for depositing a SiO2/polydopamine hybrid layer on a titanium surface to enhance the adhesion, proliferation, differentiation, and mineralization of osteoblasts.
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Affiliation(s)
- Chia-Che Ho
- Institute of Oral Science
- Chung Shan Medical University
- Taichung City 402
- Taiwan
| | - Shinn-Jyh Ding
- Institute of Oral Science
- Chung Shan Medical University
- Taichung City 402
- Taiwan
- Department of Dentistry
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20
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Gorniak T, Haraszti T, Garamus VM, Buck AR, Senkbeil T, Priebe M, Hedberg-Buenz A, Koehn D, Salditt T, Grunze M, Anderson MG, Rosenhahn A. Nano-scale morphology of melanosomes revealed by small-angle X-ray scattering. PLoS One 2014; 9:e90884. [PMID: 24621581 PMCID: PMC3951238 DOI: 10.1371/journal.pone.0090884] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 01/27/2014] [Indexed: 12/02/2022] Open
Abstract
Melanosomes are highly specialized organelles that produce and store the pigment melanin, thereby fulfilling essential functions within their host organism. Besides having obvious cosmetic consequences – determining the color of skin, hair and the iris – they contribute to photochemical protection from ultraviolet radiation, as well as to vision (by defining how much light enters the eye). Though melanosomes can be beneficial for health, abnormalities in their structure can lead to adverse effects. Knowledge of their ultrastructure will be crucial to gaining insight into the mechanisms that ultimately lead to melanosome-related diseases. However, due to their small size and electron-dense content, physiologically intact melanosomes are recalcitrant to study by common imaging techniques such as light and transmission electron microscopy. In contrast, X-ray-based methodologies offer both high spatial resolution and powerful penetrating capabilities, and thus are well suited to study the ultrastructure of electron-dense organelles in their natural, hydrated form. Here, we report on the application of small-angle X-ray scattering – a method effective in determining the three-dimensional structures of biomolecules – to whole, hydrated murine melanosomes. The use of complementary information from the scattering signal of a large ensemble of suspended organelles and from single, vitrified specimens revealed a melanosomal sub-structure whose surface and bulk properties differ in two commonly used inbred strains of laboratory mice. Whereas melanosomes in C57BL/6J mice have a well-defined surface and are densely packed with 40-nm units, their counterparts in DBA/2J mice feature a rough surface, are more granular and consist of 60-nm building blocks. The fact that these strains have different coat colors and distinct susceptibilities to pigment-related eye disease suggest that these differences in size and packing are of biological significance.
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Affiliation(s)
- Thomas Gorniak
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany; Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany; Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Tamas Haraszti
- Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany; Max-Planck-Institute for Intelligent Systems, Stuttgart, Germany
| | - Vasyl M Garamus
- Helmholtz-Zentrum Geesthacht, Zentrum für Material- und Küstenforschung GmbH, Geesthacht, Germany
| | - Andreas R Buck
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany; Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany; Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, Bochum, Germany
| | - Tobias Senkbeil
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany; Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - Marius Priebe
- Institute for X-Ray Physics, University of Göttingen, Göttingen, Germany
| | - Adam Hedberg-Buenz
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America; Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, Iowa, United States of America
| | - Demelza Koehn
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - Tim Salditt
- Institute for X-Ray Physics, University of Göttingen, Göttingen, Germany
| | - Michael Grunze
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany; Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | - Michael G Anderson
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America; Center for the Prevention and Treatment of Visual Loss, Iowa City Veterans Affairs (VA) Health Care System, Iowa City, Iowa, United States of America
| | - Axel Rosenhahn
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen, Germany; Applied Physical Chemistry, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany; Analytical Chemistry - Biointerfaces, Ruhr-University Bochum, Bochum, Germany
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21
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Vavricka CJ, Han Q, Mehere P, Ding H, Christensen BM, Li J. Tyrosine metabolic enzymes from insects and mammals: a comparative perspective. INSECT SCIENCE 2014; 21:13-19. [PMID: 23955993 DOI: 10.1111/1744-7917.12038] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/17/2013] [Indexed: 06/02/2023]
Abstract
Differences in the metabolism of tyrosine between insects and mammals present an interesting example of molecular evolution. Both insects and mammals possess fine-tuned systems of enzymes to meet their specific demands for tyrosine metabolites; however, more homologous enzymes involved in tyrosine metabolism have emerged in many insect species. Without knowledge of modern genomics, one might suppose that mammals, which are generally more complex than insects and require tyrosine as a precursor for important catecholamine neurotransmitters and for melanin, should possess more enzymes to control tyrosine metabolism. Therefore, the question of why insects actually possess more tyrosine metabolic enzymes is quite interesting. It has long been known that insects rely heavily on tyrosine metabolism for cuticle hardening and for innate immune responses, and these evolutionary constraints are likely the key answers to this question. In terms of melanogenesis, mammals also possess a high level of regulation; yet mammalian systems possess more mechanisms for detoxification whereas insects accelerate pathways like melanogenesis and therefore must bear increased oxidative pressure. Our research group has had the opportunity to characterize the structure and function of many key proteins involved in tyrosine metabolism from both insects and mammals. In this mini review we will give a brief overview of our research on tyrosine metabolic enzymes in the scope of an evolutionary perspective of mammals in comparison to insects.
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Affiliation(s)
- Christopher John Vavricka
- Research Network of Immunity and Health (RNIH), Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
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22
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Seiberg M. Age-induced hair greying - the multiple effects of oxidative stress. Int J Cosmet Sci 2013; 35:532-8. [PMID: 24033376 DOI: 10.1111/ics.12090] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 08/20/2013] [Indexed: 01/14/2023]
Abstract
An obvious sign of ageing is hair greying, or the loss of pigment production and deposition within the hair shafts. Numerous mechanisms, acting at different levels and follicular locations, contribute to hair greying, ranging from melanocyte stem cells defects to follicular melanocyte death. One key issue that is in common to these processes is oxidative damage. At the hair follicle stem cells niche, oxidative stress, accelerated by B-cell lymphoma 2 gene (BCL-2) depletion, leads to selective apoptosis and diminution of melanocyte stem cells, reducing the repopulation of newly formed anagen follicles. Melanotic bulbar melanocytes express high levels of BCL-2 to enable survival from melanogenesis- and ultraviolet A (UVA)-induced reactive oxygen species (ROS) attacks. With ageing, the bulbar melanocyte expression of anti-oxidant proteins such as BCL-2, and possibly TRP-2, is reduced, and the dedicated enzymatic anti-oxidant defence system throughout the follicle weakens, resulting in enhanced oxidative stress. A marked reduction in catalase expression and activity results in millimolar accumulation of hydrogen peroxide, contributing to bulbar melanocyte malfunction and death. Interestingly, amelanotic melanocytes at the outer root sheath (ORS) are somewhat less affected by these processes and survive for longer time even within the white, ageing hair follicles. Better understanding of the overtime susceptibility of melanocytes to oxidative stress at the different follicular locations might yield clues to possible therapies for the prevention and reversal of hair greying.
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Affiliation(s)
- M Seiberg
- Seiberg Consulting, LLC, Princeton, NJ, USA
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23
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Chen P, Li L, Wang J, Li H, Li Y, Lv Y, Lu C. BmPAH catalyzes the initial melanin biosynthetic step in Bombyx mori. PLoS One 2013; 8:e71984. [PMID: 23991017 PMCID: PMC3753331 DOI: 10.1371/journal.pone.0071984] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Accepted: 07/06/2013] [Indexed: 11/19/2022] Open
Abstract
Pigmentation during insect development is a primal adaptive requirement. In the silkworm, melanin is the primary component of larval pigments. The rate limiting substrate in melanin synthesis is tyrosine, which is converted from phenylalanine by the rate-limiting enzyme phenylalanine hydroxylase (PAH). While the role of tyrosine, derived from phenylalanine, in the synthesis of fiber proteins has long been known, the role of PAH in melanin synthesis is still unknown in silkworm. To define the importance of PAH, we cloned the cDNA sequence of BmPAH and expressed its complete coding sequence using the Bac-to-Bac baculovirus expression system. Purified recombinant protein had high PAH activity, some tryptophan hydroxylase activity, but no tyrosine hydroxylase activity, which are typical properties of PAH in invertebrates. Because melanin synthesis is most robust during the embryonic stage and larval integument recoloring stage, we injected BmPAH dsRNA into silkworm eggs and observed that decreasing BmPAH mRNA reduced neonatal larval tyrosine and caused insect coloration to fail. In vitro cultures and injection of 4th instar larval integuments with PAH inhibitor revealed that PAH activity was essential for larval marking coloration. These data show that BmPAH is necessary for melanin synthesis and we propose that conversion of phenylalanine to tyrosine by PAH is the first step in the melanin biosynthetic pathway in the silkworm.
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Affiliation(s)
- Ping Chen
- State Key Laboratory of Silkworm Genome Biology and College of Biotechnology, Southwest University, Chongqing, China ; College of Biotechnology, Southwest University, Chongqing, China
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24
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d'Ischia M, Wakamatsu K, Napolitano A, Briganti S, Garcia-Borron JC, Kovacs D, Meredith P, Pezzella A, Picardo M, Sarna T, Simon JD, Ito S. Melanins and melanogenesis: methods, standards, protocols. Pigment Cell Melanoma Res 2013; 26:616-33. [PMID: 23710556 DOI: 10.1111/pcmr.12121] [Citation(s) in RCA: 281] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Accepted: 05/17/2013] [Indexed: 01/03/2023]
Abstract
Despite considerable advances in the past decade, melanin research still suffers from the lack of universally accepted and shared nomenclature, methodologies, and structural models. This paper stems from the joint efforts of chemists, biochemists, physicists, biologists, and physicians with recognized and consolidated expertise in the field of melanins and melanogenesis, who critically reviewed and experimentally revisited methods, standards, and protocols to provide for the first time a consensus set of recommended procedures to be adopted and shared by researchers involved in pigment cell research. The aim of the paper was to define an unprecedented frame of reference built on cutting-edge knowledge and state-of-the-art methodology, to enable reliable comparison of results among laboratories and new progress in the field based on standardized methods and shared information.
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Affiliation(s)
- Marco d'Ischia
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy.
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25
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Bar-Even A, Salah Tawfik D. Engineering specialized metabolic pathways--is there a room for enzyme improvements? Curr Opin Biotechnol 2012; 24:310-9. [PMID: 23102865 DOI: 10.1016/j.copbio.2012.10.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 10/02/2012] [Accepted: 10/03/2012] [Indexed: 01/03/2023]
Abstract
Recent advances in enzyme engineering enable dramatic improvements in catalytic efficiency and/or selectivity, as well as de novo engineering of enzymes to catalyze reactions where natural enzymes are not available. Can these capabilities be utilized to transform biosynthesis pathways? Metabolic engineering is traditionally based on combining existing enzymes to give new, or modified, pathways, within a new context and/or organism. How efficient, however, are the individual enzyme components? Is there room to improve pathway performance by enzyme engineering? We discuss the differences between enzymes in central versus specialized, or secondary metabolism and highlight unique features of specialized metabolism enzymes participating in the synthesis of natural products. We argue that, for the purpose of metabolic engineering, the catalytic efficiency and selectivity of many enzymes can be improved with the aim of achieving higher rates, yields and product purities. We also note the relative abundance of spontaneous reactions in specialized metabolism, and the potential advantage of engineering enzymes that will catalyze these steps. Specialized metabolism therefore offers new opportunities to integrate enzyme and pathway engineering, thereby achieving higher metabolic efficiencies, enhanced production rates and improved product purities.
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Affiliation(s)
- Arren Bar-Even
- Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.
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Honigman JS, DiGregorio KM, Dedkov EI, Leheste JR, Leng L, Bucala R, Torres G. Distribution maps of D-dopachrome tautomerase in the mouse brain. Neuroscience 2012; 226:382-7. [PMID: 23000624 DOI: 10.1016/j.neuroscience.2012.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 09/04/2012] [Accepted: 09/05/2012] [Indexed: 11/24/2022]
Abstract
D-Dopachrome tautomerase is an enzyme related by amino acid sequence and catalytic activity to macrophage migration inhibitory factor. Both of these small molecules are pro-inflammatory cytokines mediating broad innate immune responses. Although it is well established that the gene product of D-dopachrome tautomerase is widely expressed in liver and kidney cells, no study has mapped the distribution pattern of this tautomeric enzyme in the mammalian nervous system. Here, we address this void by characterizing the cellular localization of D-dopachrome tautomerase in the adult mouse brain. Two well-characterized polyclonal antibodies were used for Western blotting and immunohistochemical localization of the endogenous tautomeric enzyme. Our results show that D-dopachrome tautomerase is present throughout the brain parenchyma with a large fraction of heterogeneous interneurons harboring a stable and robust expression of the enzyme. These data point to a potential involvement of D-dopachrome tautomerase activity in the mature mouse brain, and suggest some functional and evolutionary relationship between innate immunity and tautomerization of D-dopachrome in mammalian species.
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Affiliation(s)
- J S Honigman
- Department of Neuroscience and Histology, New York College of Osteopathic Medicine of New York Institute of Technology, Old Westbury, NY 11568, USA
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Diedrich M, Kitada T, Nebrich G, Koppelstaetter A, Shen J, Zabel C, Klose J, Mao L. Brain region specific mitophagy capacity could contribute to selective neuronal vulnerability in Parkinson's disease. Proteome Sci 2011; 9:59. [PMID: 21943346 PMCID: PMC3196908 DOI: 10.1186/1477-5956-9-59] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 09/23/2011] [Indexed: 11/30/2022] Open
Abstract
Parkinson's disease (PD) is histologically well defined by its characteristic degeneration of dopaminergic neurons in the substantia nigra pars compacta. Remarkably, divergent PD-related mutations can generate comparable brain region specific pathologies. This indicates that some intrinsic region-specificity respecting differential neuron vulnerability exists, which codetermines the disease progression. To gain insight into the pathomechanism of PD, we investigated protein expression and protein oxidation patterns of three different brain regions in a PD mouse model, the PINK1 knockout mice (PINK1-KO), in comparison to wild type control mice. The dysfunction of PINK1 presumably affects mitochondrial turnover by disturbing mitochondrial autophagic pathways. The three brain regions investigated are the midbrain, which is the location of substantia nigra; striatum, the major efferent region of substantia nigra; and cerebral cortex, which is more distal to PD pathology. In all three regions, mitochondrial proteins responsible for energy metabolism and membrane potential were significantly altered in the PINK1-KO mice, but with very different region specific accents in terms of up/down-regulations. This suggests that disturbed mitophagy presumably induced by PINK1 knockout has heterogeneous impacts on different brain regions. Specifically, the midbrain tissue seems to be most severely hit by defective mitochondrial turnover, whereas cortex and striatum could compensate for mitophagy nonfunction by feedback stimulation of other catabolic programs. In addition, cerebral cortex tissues showed the mildest level of protein oxidation in both PINK1-KO and wild type mice, indicating either a better oxidative protection or less reactive oxygen species (ROS) pressure in this brain region. Ultra-structural histological examination in normal mouse brain revealed higher incidences of mitophagy vacuoles in cerebral cortex than in striatum and substantia nigra. Taken together, the delicate balance between oxidative protection and mitophagy capacity in different brain regions could contribute to brain region-specific pathological patterns in PD.
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Affiliation(s)
- Madeleine Diedrich
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | - Tohru Kitada
- Center for Neurologic Diseases, Brigham and Women's Hospital, Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Grit Nebrich
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | - Andrea Koppelstaetter
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | - Jie Shen
- Center for Neurologic Diseases, Brigham and Women's Hospital, Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Claus Zabel
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | - Joachim Klose
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | - Lei Mao
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, D-13353 Berlin, Germany
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Zhao P, Lu Z, Strand MR, Jiang H. Antiviral, anti-parasitic, and cytotoxic effects of 5,6-dihydroxyindole (DHI), a reactive compound generated by phenoloxidase during insect immune response. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:645-52. [PMID: 21554953 PMCID: PMC3129360 DOI: 10.1016/j.ibmb.2011.04.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 03/31/2011] [Accepted: 04/14/2011] [Indexed: 05/09/2023]
Abstract
Phenoloxidase (PO) and its activation system are implicated in several defense responses of insects. Upon wounding or infection, inactive prophenoloxidase (proPO) is converted to active PO through a cascade of serine proteases and their homologs. PO generates reactive compounds such as 5,6-dihydroxyindole (DHI), which have a broad-spectrum antibacterial and antifungal activity. Here we report that DHI and its spontaneous oxidation products are also active against viruses and parasitic wasps. Preincubation of a baculovirus stock with 1.25 mM DHI for 3 h near fully disabled recombinant protein production. The LC₅₀ for lambda bacteriophage and eggs of the wasp Microplitis demolitor were 5.6 ± 2.2 and 111.0 ± 1.6 μM, respectively. The toxicity of DHI and related compounds also extended to cells derived from insects that serve as hosts for several of the aforementioned pathogens. Pretreatment of Sf9 cells with 1.0 mM DHI for 4 h resulted in 97% mortality, and LC₅₀ values of 20.3 ± 1.2 μM in buffer and 131.8 ± 1.1 μM in a culture medium. Symptoms of DHI toxicity in Sf9 cells included DNA polymerization, protein crosslinking, and lysis. Taken together, these data showed that proPO activation and DHI production is strongly toxic against various pathogens but can also damage host tissues and cells if not properly controlled.
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Affiliation(s)
- Picheng Zhao
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Zhiqiang Lu
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
| | - Michael R. Strand
- Department of Entomology, University of Georgia, Athens, GA 30602, USA
| | - Haobo Jiang
- Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK, 74078, USA
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Human hair follicle and epidermal melanocytes exhibit striking differences in their aging profile which involves catalase. J Invest Dermatol 2010; 131:979-82. [PMID: 21191398 DOI: 10.1038/jid.2010.397] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Melanization in living organisms: a perspective of species evolution. Protein Cell 2010; 1:830-41. [PMID: 21203925 DOI: 10.1007/s13238-010-0109-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 09/08/2010] [Indexed: 10/19/2022] Open
Abstract
Eumelanin is a heteropolymer that is generally composed of hydroxylated indole residues and plays diverse protective functions in various species. Melanin is derived from the amino acid tyrosine and production of melanin is a highly complex oxidative process with a number of steps that can either proceed enzymatically or non-enzymatically. Although melanin plays important protective roles in many species, during melanization, particularly in steps that can proceed non-enzymatically, many toxic intermediates are produced, including semiquinones, dopaquinone, indole-quinones and moreover, the production of many reactive oxygen species. To mitigate the production of reactive species, a number of proteins that regulate the biochemical process of melanization have evolved in various living species, which is closely related to adaptation and physiological requirements. In this communication, we discuss differences between non-enzymatic and enzymatic processes of melanization and the enzymatic regulation of melanization in difference species with an emphasis on differences between mammals and insects. Comparison between melanization and insect sclerotization is also emphasized which raises some interesting questions about the current models of these pathways.
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Abstract
Dopachrome tautomerase (DCT) plays a critical role in lowering the oxidative stress resulting from melanogenesis. Levels of DCT are elevated in melanoma cell lines that are especially resistant to chemotherapy and radiation. DCT is processed as a melanoma antigen and is a potential target for immunotherapy. In order to establish a more complete understanding of the role that DCT may play in the etiology and treatment of melanoma skin cancer, isolation of highly pure and properly processed protein is necessary. Purification of native DCT has been problematic due to a hydrophobic transmembrane anchor and interactions with melanin. In this study, DCT was expressed, without its carboxy-terminal transmembrane region using an Sf9 insect cell protein expression system and its recombinant protein was purified by various chromatographic techniques. Analysis of DCT tryptic peptides by MALDI-TOF/TOF determined N-glycosylation as a primary post-translational modification. Our success in the expression of soluble mammalian DCT and the characterization of N-glycosylation sites is a useful reference toward the comprehensive understanding of the structure/function relationship of mammalian DCT.
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Trantow CM, Hedberg-Buenz A, Iwashita S, Moore SA, Anderson MG. Elevated oxidative membrane damage associated with genetic modifiers of Lyst-mutant phenotypes. PLoS Genet 2010; 6:e1001008. [PMID: 20617205 PMCID: PMC2895641 DOI: 10.1371/journal.pgen.1001008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Accepted: 05/27/2010] [Indexed: 01/16/2023] Open
Abstract
LYST is a large cytosolic protein that influences the biogenesis of lysosome-related organelles, and mutation of the encoding gene, LYST, can cause Chediak-Higashi syndrome. Recently, Lyst-mutant mice were recognized to also exhibit an iris disease resembling exfoliation syndrome, a common cause of glaucoma in humans. Here, Lyst-mutant iris phenotypes were used in a search for genes that influence Lyst pathways. In a candidate gene–driven approach, albino Lyst-mutant mice homozygous for a mutation in Tyr, whose product is key to melanin synthesis within melanosomes, exhibited complete rescue of Lyst-mutant iris phenotypes. In a genetic background–driven approach using a DBA/2J strain of congenic mice, an interval containing Tyrp1 enhanced Lyst-dependent iris phenotypes. Thus, both experimental approaches implicated the melanosome, an organelle that is a potential source of oxidative stress, as contributing to the disease phenotype. Confirming an association with oxidative damage, Lyst mutation resulted in genetic context–sensitive changes in iris lipid hydroperoxide levels, being lowest in albino and highest in DBA/2J mice. Surprisingly, the DBA/2J genetic background also exposed a late-onset neurodegenerative phenotype involving cerebellar Purkinje-cell degeneration. These results identify an association between oxidative damage to lipid membranes and the severity of Lyst-mutant phenotypes, revealing a new mechanism that contributes to pathophysiology involving LYST. LYST is a poorly understood protein involved in hereditary disease. Mutations in the encoding gene cause Chediak-Higashi syndrome, a rare lethal disease affecting multiple tissues of the body. Mutations in Lyst also recapitulate features of exfoliation syndrome, a common disease affecting the anterior chamber of the eye. Unfortunately, the Lyst gene is quite large, rendering it difficult to study by many molecular and cellular approaches. Here, we use a genetic approach in mice to identify additional genetic pathways which might modify, or prevent, the ill consequences associated with Lyst mutation. Our experiments demonstrate that Lyst mutation results in elevated levels of oxidative damage to lipid membranes. These results identify a previously unrecognized consequence of Lyst mutation and a modifiable pathway of potential clinical relevance in humans. Ultimately, knowledge of these events will contribute to the design of new therapeutic strategies allowing a similar alleviation of disease in humans.
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Affiliation(s)
- Colleen M. Trantow
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - Adam Hedberg-Buenz
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - Sachiyo Iwashita
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
| | - Steven A. Moore
- Department of Pathology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Michael G. Anderson
- Department of Molecular Physiology and Biophysics, The University of Iowa, Iowa City, Iowa, United States of America
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
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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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Esson D, Armour M, Mundy P, Schobert CS, Dubielzig RR. The histopathological and immunohistochemical characteristics of pigmentary and cystic glaucoma in the Golden Retriever. Vet Ophthalmol 2009; 12:361-8. [DOI: 10.1111/j.1463-5224.2009.00732.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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35
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Vad NM, Yount G, Moore D, Weidanz J, Moridani MY. Biochemical mechanism of acetaminophen (APAP) induced toxicity in melanoma cell lines. J Pharm Sci 2009; 98:1409-25. [PMID: 18759348 DOI: 10.1002/jps.21505] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this work, we investigated the biochemical mechanism of acetaminophen (APAP) induced toxicity in SK-MEL-28 melanoma cells using tyrosinase enzyme as a molecular cancer therapeutic target. Our results showed that APAP was metabolized 87% by tyrosinase at 2 h incubation. AA and NADH, quinone reducing agents, were significantly depleted during APAP oxidation by tyrosinase. The IC(50) (48 h) of APAP towards SK-MEL-28, MeWo, SK-MEL-5, B16-F0, and B16-F10 melanoma cells was 100 microM whereas it showed no significant toxicity towards BJ, Saos-2, SW-620, and PC-3 nonmelanoma cells, demonstrating selective toxicity towards melanoma cells. Dicoumarol, a diaphorase inhibitor, and 1-bromoheptane, a GSH depleting agent, enhanced APAP toxicity towards SK-MEL-28 cells. AA and GSH were effective in preventing APAP induced melanoma cell toxicity. Trifluoperazine and cyclosporin A, inhibitors of permeability transition pore in mitochondria, significantly prevented APAP melanoma cell toxicity. APAP caused time and dose-dependent decline in intracellular GSH content in SK-MEL-28, which preceded cell toxicity. APAP led to ROS formation in SK-MEL-28 cells which was exacerbated by dicoumarol and 1-bromoheptane whereas cyslosporin A and trifluoperazine prevented it. Our investigation suggests that APAP is a tyrosinase substrate, and that intracellular GSH depletion, ROS formation and induced mitochondrial toxicity contributed towards APAP's selective toxicity in SK-MEL-28 cells.
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Affiliation(s)
- Nikhil M Vad
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, Texas 79106, USA
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36
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Petersen-Jones SM, Mentzer AL, Dubielzig RR, Render JA, Steficek BA, Kiupel M. Ocular melanosis in the Cairn Terrier: histopathological description of the condition, and immunohistological and ultrastructural characterization of the characteristic pigment-laden cells. Vet Ophthalmol 2008; 11:260-8. [DOI: 10.1111/j.1463-5224.2008.00640.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Petersen-Jones SM, Forcier J, Mentzer AL. Ocular melanosis in the Cairn Terrier: clinical description and investigation of mode of inheritance. Vet Ophthalmol 2007; 10 Suppl 1:63-9. [DOI: 10.1111/j.1463-5224.2007.00558.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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38
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Anderson MG, Hawes NL, Trantow CM, Chang B, John SWM. Iris phenotypes and pigment dispersion caused by genes influencing pigmentation. Pigment Cell Melanoma Res 2007; 21:565-78. [PMID: 18715234 DOI: 10.1111/j.1755-148x.2008.00482.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Spontaneous mutations altering mouse coat colors have been a classic resource for discovery of numerous molecular pathways. Although often overlooked, the mouse iris is also densely pigmented and easily observed, thus representing a similarly powerful opportunity for studying pigment cell biology. Here, we present an analysis of iris phenotypes among 16 mouse strains with mutations influencing melanosomes. Many of these strains exhibit biologically and medically relevant phenotypes, including pigment dispersion, a common feature of several human ocular diseases. Pigment dispersion was identified in several strains with mutant alleles known to influence melanosomes, including beige, light, and vitiligo. Pigment dispersion was also detected in the recently arising spontaneous coat color variant, nm2798. We have identified the nm2798 mutation as a missense mutation in the Dct gene, an identical re-occurrence of the slaty light mutation. These results suggest that dysregulated events of melanosomes can be potent contributors to the pigment dispersion phenotype. Combined, these findings illustrate the utility of studying iris phenotypes as a means of discovering new pathways, and re-linking old ones, to processes of pigmented cells in health and disease.
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Affiliation(s)
- Michael G Anderson
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.
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Zhang X, Erb C, Flammer J, Nau WM. Absolute Rate Constants for the Quenching of Reactive Excited States by Melanin and Related 5,6-Dihydroxyindole Metabolites: Implications for Their Antioxidant Activity. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2000)0710524arcftq2.0.co2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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40
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Fowler DM, Koulov AV, Balch WE, Kelly JW. Functional amyloid--from bacteria to humans. Trends Biochem Sci 2007; 32:217-24. [PMID: 17412596 DOI: 10.1016/j.tibs.2007.03.003] [Citation(s) in RCA: 811] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 02/08/2007] [Accepted: 03/21/2007] [Indexed: 01/22/2023]
Abstract
Amyloid--a fibrillar, cross beta-sheet quaternary structure--was first discovered in the context of human disease and tissue damage, and was thought to always be detrimental to the host. Recent studies have identified amyloid fibers in bacteria, fungi, insects, invertebrates and humans that are functional. For example, human Pmel17 has important roles in the biosynthesis of the pigment melanin, and the factor XII protein of the hemostatic system is activated by amyloid. Functional amyloidogenesis in these systems requires tight regulation to avoid toxicity. A greater understanding of the diverse physiological applications of this fold has the potential to provide a fresh perspective for the treatment of amyloid diseases.
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Affiliation(s)
- Douglas M Fowler
- Department of Chemistry and The Skaggs Institute of Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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McNeill MS, Paulsen J, Bonde G, Burnight E, Hsu MY, Cornell RA. Cell death of melanophores in zebrafish trpm7 mutant embryos depends on melanin synthesis. J Invest Dermatol 2007; 127:2020-30. [PMID: 17290233 DOI: 10.1038/sj.jid.5700710] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Transient receptor potential melastatin 7 (TRPM7) is a broadly expressed, non-selective cation channel. Studies in cultured cells implicate TRPM7 in regulation of cell growth, spreading, and survival. However, zebrafish trpm7 homozygous mutants display death of melanophores and temporary paralysis, but no gross morphological defects during embryonic stages. This phenotype implies that melanophores are unusually sensitive to decreases in Trpm7 levels, a hypothesis we investigate here. We find that pharmacological inhibition of caspases does not rescue melanophore viability in trpm7 mutants, implying that melanophores die by a mechanism other than apoptosis. Consistent with this possibility, ultrastructural analysis of dying melanophores in trpm7 mutants reveals abnormal melanosomes and evidence of a ruptured plasma membrane, indicating that cell death occurs by necrosis. Interestingly, inhibition of melanin synthesis largely prevents melanophore cell death in trpm7 mutants. These results suggest that melanophores require Trpm7 in order to detoxify intermediates of melanin synthesis. We find that unlike TRPM1, TRPM7 is expressed in human melanoma cell lines, indicating that these cells may also be sensitized to reduction of TRPM7 levels.
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Affiliation(s)
- Matthew S McNeill
- Interdisciplinary Graduate Program in Neuroscience, University of Iowa, Iowa City, Iowa, USA
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Murphy BP, Banks HD. Synthesis of 5,6-Dihydroxyindole: A Novel Reductive Cyclization of (E)-4,5-Dihydroxy-2,β-Dinitrostyrene. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397918508063806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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43
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Anderson MG, Haraszti T, Petersen GE, Wirick S, Jacobsen C, John SWM, Grunze M. Scanning transmission X-ray microscopic analysis of purified melanosomes of the mouse iris. Micron 2006; 37:689-98. [PMID: 16723235 DOI: 10.1016/j.micron.2006.03.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2006] [Revised: 03/14/2006] [Accepted: 03/15/2006] [Indexed: 11/17/2022]
Abstract
Melanosomes are specialized intracellular membrane bound organelles that produce and store melanin pigment. The composition of melanin and distribution of melanosomes determine the color of many mammalian tissues, including the hair, skin, and iris. However, the presence of melanosomes within a tissue carries potentially detrimental risks related to the cytotoxic indole-quinone intermediates produced during melanin synthesis. In order to study melanosomal molecules, including melanin and melanin-related intermediates, we have refined methods allowing spectromicroscopic analysis of purified melanosomes using scanning transmission X-ray microscopy. Here, we present for the first time absorption data for melanosomes at the carbon absorption edge ranging from 284 to 290 eV. High-resolution images of melanosomes at discrete energies demonstrate that fully melanized mature melanosomes are internally non-homogeneous, suggesting the presence of an organized internal sub-structure. Spectra of purified melanosomes are complex, partially described by a predominating absorption band at 288.4 eV with additional contributions from several minor bands. Differences in these spectra were detectable between samples from two strains of inbred mice known to harbor genetically determined melanosomal differences, DBA/2J and C57BL/6J, and are likely to represent signatures arising from biologically relevant and tractable phenomena.
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Affiliation(s)
- Michael G Anderson
- Department of Physiology and Biophysics, University of Iowa, Iowa City, IA 52242, United States.
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Plonka PM, Handjiski B, Michalczyk D, Popik M, Paus R. Oral zinc sulphate causes murine hair hypopigmentation and is a potent inhibitor of eumelanogenesis in vivo. Br J Dermatol 2006; 155:39-49. [PMID: 16792750 DOI: 10.1111/j.1365-2133.2006.07376.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND C57BL/6 a/a mice have been widely used to study melanogenesis, including in electron paramagnetic resonance (EPR) studies. Zinc cations modulate melanogenesis, but the net effect of Zn2+ in vivo is unclear, as the reported effects of Zn2+ on melanogenesis are ambiguous: zinc inhibits tyrosinase and glutathione reductase in vitro, but also enhances the activity of dopachrome tautomerase (tyrosinase-related protein-2) and has agonistic effects on melanocortin receptor signalling. OBJECTIVES To determine in a C57BL/6 a/a murine pilot study whether excess zinc ions inhibit, enhance or in any other way alter hair follicle melanogenesis in vivo, and to test the usefulness of EPR for this study. METHODS ZnSO(4).7H2O was continuously administered orally to C57BL/6 a/a mice during spontaneous and depilation-induced hair follicle cycling (20 mg mL-1; in drinking water; mean+/-SD daily dose 1.2+/-0.53 mL), and hair pigmentation was examined macroscopically, by routine histology and by EPR. RESULTS Oral zinc cations induced a bright brown lightening of new hair shafts produced during anagen, but without inducing an EPR-detectable switch from eumelanogenesis to phaeomelanogenesis. The total content of melanin in the skin and hair shafts during the subsequent telogen phase, i.e. after completion of a full hair cycle, was significantly reduced in Zn-treated mice (P=0.0005). Compared with controls, melanin granules in precortical hair matrix keratinocytes, hair bulb melanocytes and hair shafts of zinc-treated animals were reduced and poorly pigmented. Over the course of several hair cycles, lasting hair shaft depigmentation was seen during long-term exposure to high-dose oral Zn2+. CONCLUSIONS High-dose oral Zn2+ is a potent downregulator of eumelanin content in murine hair shafts in vivo. The C57BL/6 mouse model offers an excellent tool for further dissecting the as yet unclear underlying molecular basis of this phenomenon, while EPR technology is well suited for the rapid, qualitative and quantitative monitoring of hair pigmentation changes.
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Affiliation(s)
- P M Plonka
- Department of Biophysics, Faculty of Biotechnology, Jagiellonian University, ul. Gronostajowa 7, PL-30-387 Krakow, Poland, and Department of Dermatology, University Hospital Schleswig-Holstein, Lübeck, Germany.
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Anderson MG, Libby RT, Mao M, Cosma IM, Wilson LA, Smith RS, John SWM. Genetic context determines susceptibility to intraocular pressure elevation in a mouse pigmentary glaucoma. BMC Biol 2006; 4:20. [PMID: 16827931 PMCID: PMC1543659 DOI: 10.1186/1741-7007-4-20] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Accepted: 07/07/2006] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND DBA/2J (D2) mice develop an age-related form of glaucoma. Their eyes progressively develop iris pigment dispersion and iris atrophy followed by increased intraocular pressure (IOP) and glaucomatous optic nerve damage. Mutant alleles of the Gpnmb and Tyrp1 genes are necessary for the iris disease, but it is unknown whether alleles of other D2 gene(s) are necessary for the distinct later stages of disease. We initiated a study of congenic strains to further define the genetic requirements and disease mechanisms of the D2 glaucoma. RESULTS To further understand D2 glaucoma, we created congenic strains of mice on the C57BL/6J (B6) genetic background. B6 double-congenic mice carrying D2-derived Gpnmb and Tyrp1 mutations develop a D2-like iris disease. B6 single-congenics with only the Gpnmb and Tyrp1 mutations develop milder forms of iris disease. Genetic epistasis experiments introducing a B6 tyrosinase mutation into the congenic strains demonstrated that both the single and double-congenic iris diseases are rescued by interruption of melanin synthesis. Importantly, our experiments analyzing mice at ages up to 27 months indicate that the B6 double-congenic mice are much less prone to IOP elevation and glaucoma than are D2 mice. CONCLUSION As demonstrated here, the Gpnmb and Tyrp1 iris phenotypes are both individually dependent on tyrosinase function. These results support involvement of abnormal melanosomal events in the diseases caused by each gene. In the context of the inbred D2 mouse strain, the glaucoma phenotype is clearly influenced by more genes than just Gpnmb and Tyrp1. Despite the outward similarity of pigment-dispersing iris disease between D2 and the B6 double-congenic mice, the congenic mice are much less susceptible to developing high IOP and glaucoma. These new congenic strains provide a valuable new resource for further studying the genetic and mechanistic complexity of this form of glaucoma.
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Affiliation(s)
- Michael G Anderson
- The Jackson Laboratory, Bar Harbor, ME, USA
- Department of Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | | | - Mao Mao
- Department of Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | | | | | | | - Simon WM John
- The Jackson Laboratory, Bar Harbor, ME, USA
- Howard Hughes Medical Institute, Bar Harbor, ME, USA
- Tufts University School of Medicine, Boston, MA, USA
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Bonfigli A, Zarivi O, Colafarina S, Cimini AM, Ragnelli AM, Aimola P, Natali PG, Cerù MP, Amicarelli F, Miranda M. Human glioblastoma ADF cells express tyrosinase, L-tyrosine hydroxylase and melanosomes and are sensitive to L-tyrosine and phenylthiourea. J Cell Physiol 2006; 207:675-82. [PMID: 16447258 DOI: 10.1002/jcp.20603] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Melanocytes and neuroblasts share the property of transforming L-tyrosine through two distinct metabolic pathways leading to melanogenesis and catecholamine synthesis, respectively. While tyrosinase (TYR) activity has been shown to be expressed by neuroblastoma it remains to be established as to whether also glioblastomas cells are endowed with this property. We have addressed this issue using the human continuous glioblastoma cell line ADF. We demonstrated that these cells possess tyrosinase as well as L-tyrosine hydroxylase (TH) activity and synthesize melanosomes. Because the two pathways are potentially cyto-genotoxic due to production of quinones, semiquinones, and reactive oxygen species (ROS), we have also investigated the expression of the peroxisomal proliferators activated receptor alpha (PPARalpha) and nuclear factor-kB (NFkB) transcription factor as well the effect of L-tyrosine concentration on cell survival. We report that L-tyrosine down-regulates PPARalpha expression in ADF cells but not neuroblastoma and that this aminoacid and phenylthiourea (PTU) induces apoptosis in glioblastoma and neuroblastoma.
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Affiliation(s)
- Antonella Bonfigli
- Department of Basic and Applied Biology, University of L'Aquila, Via Vetoio, L'Aquila, Italy
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Fowler DM, Koulov AV, Alory-Jost C, Marks MS, Balch WE, Kelly JW. Functional amyloid formation within mammalian tissue. PLoS Biol 2006; 4:e6. [PMID: 16300414 PMCID: PMC1288039 DOI: 10.1371/journal.pbio.0040006] [Citation(s) in RCA: 591] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Accepted: 10/31/2005] [Indexed: 11/19/2022] Open
Abstract
Amyloid is a generally insoluble, fibrous cross-β sheet protein aggregate. The process of amyloidogenesis is associated with a variety of neurodegenerative diseases including Alzheimer, Parkinson, and Huntington disease. We report the discovery of an unprecedented functional mammalian amyloid structure generated by the protein Pmel17. This discovery demonstrates that amyloid is a fundamental nonpathological protein fold utilized by organisms from bacteria to humans. We have found that Pmel17 amyloid templates and accelerates the covalent polymerization of reactive small molecules into melanin—a critically important biopolymer that protects against a broad range of cytotoxic insults including UV and oxidative damage. Pmel17 amyloid also appears to play a role in mitigating the toxicity associated with melanin formation by sequestering and minimizing diffusion of highly reactive, toxic melanin precursors out of the melanosome. Intracellular Pmel17 amyloidogenesis is carefully orchestrated by the secretory pathway, utilizing membrane sequestration and proteolytic steps to protect the cell from amyloid and amyloidogenic intermediates that can be toxic. While functional and pathological amyloid share similar structural features, critical differences in packaging and kinetics of assembly enable the usage of Pmel17 amyloid for normal function. The discovery of native Pmel17 amyloid in mammals provides key insight into the molecular basis of both melanin formation and amyloid pathology, and demonstrates that native amyloid (amyloidin) may be an ancient, evolutionarily conserved protein quaternary structure underpinning diverse pathways contributing to normal cell and tissue physiology. The authors show that native Pmel17 amyloid found in mammalian melanosomes accelerates melanin synthesis.
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Affiliation(s)
- Douglas M Fowler
- 1 Department of Chemistry and The Skaggs Institute of Chemical Biology, The Scripps Research Institute, La Jolla, California, United States of America
| | - Atanas V Koulov
- 2 Department of Cell Biology and the Institute for Childhood and Neglected Diseases, The Scripps Research Institute, La Jolla, California, United States of America
| | - Christelle Alory-Jost
- 2 Department of Cell Biology and the Institute for Childhood and Neglected Diseases, The Scripps Research Institute, La Jolla, California, United States of America
| | - Michael S Marks
- 3 Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - William E Balch
- 2 Department of Cell Biology and the Institute for Childhood and Neglected Diseases, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jeffery W Kelly
- 1 Department of Chemistry and The Skaggs Institute of Chemical Biology, The Scripps Research Institute, La Jolla, California, United States of America
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Huang CY, Christensen BM, Chen CC. Role of dopachrome conversion enzyme in the melanization of filarial worms in mosquitoes. INSECT MOLECULAR BIOLOGY 2005; 14:675-82. [PMID: 16313567 DOI: 10.1111/j.1365-2583.2005.00597.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Melanization is an effective defence reaction of mosquito hosts against invading parasites. In mosquitoes, the biosynthesis of melanin is initiated by the hydroxylation of tyrosine to DOPA by phenoloxidase (PO). DOPA is a branch point of the melanization reaction; it may be oxidized to dopaquinone by PO or be decarboxylated to dopamine by dopa decarboxylase. Further oxidation of dopaquinone by PO produces dopachrome. Dopachrome is then converted to 5, 6-dihydroxyindole by dopachrome conversion enzyme (DCE) to produce melanin. The conversion of dopachrome is a rate-limiting step of the melanization reaction, and the presence of PO and DCE significantly accelerates melanization reactions. In this study, a cDNA encoding DCE was cloned from the mosquito Armigeres subalbatus. Real-time PCR analysis revealed increased transcripts from haemocytes in microfilariae (mf)-inoculated mosquitoes. Gene silencing using double-stranded RNA was used to elucidate the role of DCE in the melanization reaction of parasites in Ar. subalbatus. The levels of both DCE transcripts and protein in gene knockdown mosquitoes were dramatically reduced. Compared with controls, the degree of melanization of mf in DCE-knockdown mosquitoes was significantly decreased. These results suggest that DCE is a critical enzyme that is required for effective melanization immune responses.
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Affiliation(s)
- C-Y Huang
- Department of Tropical Medicine, National Yang-Ming University, Taipei, Taiwan
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Abstract
Glaucoma describes a group of diseases that kill retinal ganglion cells. There are different types of glaucoma, and each appears to be genetically heterogeneous. Different glaucoma genes have been identified, but these genes account for only a small proportion of glaucoma. Most glaucoma cases appear to be multifactorial, and are likely affected by multiple interacting loci. A number of genetic susceptibility factors have been suggested to contribute to glaucoma. These factors fit into two broad groups, those affecting intraocular pressure and those important in modulating retinal ganglion cell viability. Defining the complex genetics of glaucoma will require significant further study of the human disease and animal models. Genetic approaches are essential and will be enhanced by recently developed genomic and proteomic technologies. These technologies will provide valuable clues about pathogenesis for subsequent testing. In this review, we focus on endogenous genetic susceptibility factors and on how experimental studies will be valuable for dissecting the multifactorial complexity of their interactions.
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Nappi AJ, Christensen BM. Melanogenesis and associated cytotoxic reactions: applications to insect innate immunity. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 35:443-459. [PMID: 15804578 DOI: 10.1016/j.ibmb.2005.01.014] [Citation(s) in RCA: 377] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Revised: 01/05/2005] [Accepted: 01/07/2005] [Indexed: 05/24/2023]
Abstract
Insects transmit the causative agents for such debilitating diseases as malaria, lymphatic filariases, sleeping sickness, Chagas' disease, leishmaniasis, river blindness, Dengue, and yellow fever. The persistence of these diseases provides testimony to the genetic capacity of parasites to evolve strategies that ensure their successful development in two genetically diverse host species: insects and mammals. Current efforts to address the problems posed by insect-borne diseases benefit from a growing understanding of insect and mammalian immunity. Of considerable interest are recent genomic investigations that show several similarities in the innate immune effector responses and associated regulatory mechanisms manifested by insects and mammals. One notable exception, however, is the nearly universal presence of a brown-black pigment accompanying cellular innate immunity in insects. This response, which is unique to arthropods and certain other invertebrates, has focused attention on the elements involved in pigment synthesis as causing or contributing to the death of the parasite, and has even prompted speculation that the enzyme cascade mediating melanogenesis constitutes an ill-defined recognition mechanism. Experimental evidence defining the role of melanin and its precursors in insect innate immunity is severely lacking. A great deal of what is known about melanogenesis comes from studies of the process occurring in mammalian systems, where the pigment is synthesized by such diverse cells as those comprising portions of the skin, hair, inner ear, brain, and retinal epithelium. Fortunately, many of the components in the metabolic pathways leading to the formation of melanin have been found to be common to both insects and mammals. This review examines some of the factors that influence enzyme-mediated melanogenic responses, and how these responses likely contribute to blood cell-mediated, target-specific cytotoxicity in immune challenged insects.
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Affiliation(s)
- A J Nappi
- Department of Animal Health and Biomedical Sciences, University of Wisconsin-Madison, WI 53706, USA.
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