Melanins: Skin Pigments and Much More—Types, Structural Models, Biological Functions, and Formation Routes

New Journal of Science, Journal Year: 2014, Volume and Issue: 2014, P. 1 - 28

Published: March 18, 2014

This review presents a general view of all types melanin in organisms. Melanin is frequently considered just an animal cutaneous pigment and treated separately from similar fungal or bacterial pigments. Similarities concerning the phenol precursors common patterns formation routes are discussed. All melanins formed first enzymatically-controlled phase, generally phenolase, second phase characterized by uncontrolled polymerization oxidized intermediates. In that quinones derived oxidation play crucial role. Concerning functions, show feature, protective role, but they not merely photoprotective pigments against UV sunlight. pathogenic microorganisms, melanization becomes virulence factor since protects microbial cells defense mechanisms infected host. turn, some tissues where sunlight radiation potential threat. Then, their redox, metal chelating, free radical scavenging properties more important than light absorption capacity. These sometimes behave as double-edged sword, inhibition melanogenesis desirable different cells. biochemistry active field research dermatological, biomedical, cosmetical, microbiological points view, well fruit technology.

Language: Английский

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Tyrosinase: The four oxidation states of the active site and their relevance to enzymatic activation, oxidation and inactivation

Bioorganic & Medicinal Chemistry, Journal Year: 2014, Volume and Issue: 22(8), P. 2388 - 2395

Published: March 5, 2014

Language: Английский

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Molluscan shell colour

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2016, Volume and Issue: 92(2), P. 1039 - 1058

Published: March 23, 2016

ABSTRACT The phylum M ollusca is highly speciose, and the largest in marine realm. great majority of molluscs are shelled, including nearly all bivalves, most gastropods some cephalopods. fabulous diverse colours patterns molluscan shells widely recognised have been appreciated for hundreds years by collectors scientists alike. They serve taxonomists as characters that can be used to recognise distinguish species, however their function animal sometimes less clear has focus many ecological evolutionary studies. Despite these studies, almost nothing known about evolution colour shells. This review summarises first time major findings disparate studies relevant shell discusses importance colour, effects visual non‐visual selection, diet abiotic factors. I also summarise evidence heritability taxa recent efforts understand molecular mechanisms underpinning synthesis colours. describe main pigments found (carotenoids, melanin tetrapyrroles, porphyrins bile pigments), durability fossil record. Finally suggest appear distributed a phylogenetically manner likely energetically costly.

Language: Английский

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Melanocytes and Their Diseases

Cold Spring Harbor Perspectives in Medicine, Journal Year: 2014, Volume and Issue: 4(5), P. a017046 - a017046

Published: May 1, 2014

Yuji Yamaguchi1 and Vincent J. Hearing2 1Medical, AbbVie GK, Mita, Tokyo 108-6302, Japan 2Laboratory of Cell Biology, National Cancer Institute, Institutes Health, Bethesda, Maryland 20892 Correspondence: hearingv{at}nih.gov

Language: Английский

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Melanosomes: Biogenesis, Properties, and Evolution of an Ancient Organelle

Physiological Reviews, Journal Year: 2018, Volume and Issue: 99(1), P. 1 - 19

Published: Sept. 26, 2018

Melanosomes are organelles that produce and store melanin, a widespread biological pigment with unique suite of properties including high refractive index, semiconducting capabilities, material stiffness, fossilization potential. They involved in numerous critical functions organisms across the tree life. Individual components such as melanin chemistry melanosome development have recently been addressed, but broad synthesis is needed. Here, we review hierarchical structure, development, functions, evolution melanosomes. We highlight variation morphology how these may relate to function. For example, what known chemical differences between different types (eumelanin, pheomelanin, allomelanin) whether/how relates color. integrate distribution living from fossil record hypotheses on its evolution. suggest was present life forms early evolutionary history melanosomes evolved at origin organelles. Throughout, discuss (sometimes gaping) holes our knowledge areas need particular attention move forward understanding still-mysterious materials they contain.

Language: Английский

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Direct chemical evidence for eumelanin pigment from the Jurassic period

Proceedings of the National Academy of Sciences, Journal Year: 2012, Volume and Issue: 109(26), P. 10218 - 10223

Published: May 21, 2012

Melanin is a ubiquitous biological pigment found in bacteria, fungi, plants, and animals. It has diverse range of ecological biochemical functions, including display, evasion, photoprotection, detoxification, metal scavenging. To date, evidence melanin fossil organisms relied entirely on indirect morphological chemical analyses. Here, we apply direct techniques to categorically demonstrate the preservation eumelanin two > 160 Ma Jurassic cephalopod ink sacs confirm its similarity modern cephalopod, Sepia officinalis . Identification characterization degradation-resistant may provide insights into roles ancient organisms.

Language: Английский

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Reconstruction of Microraptor and the Evolution of Iridescent Plumage

Science, Journal Year: 2012, Volume and Issue: 335(6073), P. 1215 - 1219

Published: March 8, 2012

Iridescent feather colors involved in displays of many extant birds are produced by nanoscale arrays melanin-containing organelles (melanosomes). Data relevant to the evolution these and properties melanosomes their generation have been limited. A data set sampling variables avian reveals that those forming most iridescent distinctly narrow. Quantitative comparison with melanosome imprints densely sampled from a previously unknown specimen Early Cretaceous feathered Microraptor predicts its plumage was predominantly iridescent. The capacity for simple is thus minimally inferred paravian dinosaurs. This finding estimation feathering consistent an ornamental function tail suggest centrality signaling early color.

Language: Английский

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Laser spectrometry for multi-elemental imaging of biological tissues

Scientific Reports, Journal Year: 2014, Volume and Issue: 4(1)

Published: Aug. 14, 2014

An increasing interest has arisen in research focused on metallic and organic ions that play crucial roles both physiological pathological metabolic processes. Current methods for the observation of trace elements biological tissues at microscopic spatial resolution often require equipment with high complexity. We demonstrate a novel approach an all-optical design multi-elemental scanning imaging, which is unique among elemental detection because its full compatibility standard optical microscopy. This based laser-induced breakdown spectroscopy (LIBS), allows tissue sample to be directly detected quantified under atmospheric pressure. successfully applied this method murine kidneys 10 µm ppm-level limit analyze renal clearance nanoparticles. These results offer new insight into use laser spectrometry biomedical applications field label-free mapping tissues.

Language: Английский

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Molecular preservation of the pigment melanin in fossil melanosomes

Nature Communications, Journal Year: 2012, Volume and Issue: 3(1)

Published: May 8, 2012

Language: Английский

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Mimicking Melanosomes: Polydopamine Nanoparticles as Artificial Microparasols

ACS Central Science, Journal Year: 2017, Volume and Issue: 3(6), P. 564 - 569

Published: May 18, 2017

A primary role of melanin in skin is the prevention UV-induced nuclear DNA damage to human cells, where it serves screen out harmful UV radiation. Melanin delivered keratinocytes after being excreted as melanosomes from melanocytes. Defects production humans can cause diseases, many which currently lack effective treatments due their genetic origins (e.g., cancer, vitiligo, and albinism). The widespread prevalence melanin-related diseases an increasing interest performance various polymeric materials related necessitates novel synthetic routes for preparing melanin-like materials. In this work, we prepared nanoparticles (MelNPs) via spontaneous oxidation dopamine, biocompatible, analogues naturally occurring melanosomes, investigated uptake, transport, distribution, UV-protective capabilities keratinocytes. Critically, demonstrate that MelNPs are endocytosed, undergo perinuclear aggregation, form a supranuclear cap, or so-called microparasol epidermal (HEKa), mimicking behavior natural melananosomes terms cellular distribution fact they serve protect cells damage.

Language: Английский

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