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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An integrative approach to understanding bird origins

Science, Journal Year: 2014, Volume and Issue: 346(6215)

Published: Dec. 11, 2014

Recent discoveries of spectacular dinosaur fossils overwhelmingly support the hypothesis that birds are descended from maniraptoran theropod dinosaurs, and furthermore, demonstrate distinctive bird characteristics such as feathers, flight, endothermic physiology, unique strategies for reproduction growth, a novel pulmonary system originated among Mesozoic terrestrial dinosaurs. The transition ground-living to flight-capable dinosaurs now probably represents one best-documented major evolutionary transitions in life history. studies developmental biology other disciplines provide additional insights into how evolved. iconic features extant most part evolved gradual stepwise fashion throughout archosaur evolution. However, new data also highlight occasional bursts morphological novelty at certain stages particularly close origin an unavoidable complex, mosaic distribution on tree. Research origins provides premier example paleontological neontological can interact reveal complexity innovations, answer key questions, lead research directions. A better understanding requires multifaceted integrative approaches, yet necessarily final test any model.

Language: Английский

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The origin and early radiation of dinosaurs

Earth-Science Reviews, Journal Year: 2010, Volume and Issue: 101(1-2), P. 68 - 100

Published: May 5, 2010

Language: Английский

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Plumage Color Patterns of an Extinct Dinosaur

Science, Journal Year: 2010, Volume and Issue: 327(5971), P. 1369 - 1372

Published: Feb. 5, 2010

Dinosaur Plumage Coloration and appearance provide important behavioral evolutionary information in animals. However, for the most part, we do not know coloration of fossil terrestrial Li et al. (p. 1369 , published online 4 February) have reconstructed a theropod dinosaur by mapping features its well-preserved feathers comparing them with modern samples from birds. Feather color is partly determined melanosome density shape, this preserved recently discovered China. The was gray white limbs had reddish crest speckled face.

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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Microbial production of melanin and its various applications

World Journal of Microbiology and Biotechnology, Journal Year: 2020, Volume and Issue: 36(11)

Published: Oct. 12, 2020

Abstract Melanins are natural biopolymers that known to contribute different biological processes and protect organisms from adverse environmental conditions. During the past decade, melanins have attracted increasing attention for their use in organic semiconductors bioelectronics, drug delivery, photoprotection bioremediation. Although considerable advances these fields been achieved, real-world applications of still scarce, probably due limited expensive source melanin. Nevertheless, recent biotechnological allowed relatively large-scale production microbial melanins, which could replace current commercial In this review, we first describe melanin sources highlight advantages disadvantages each method. Our focus is on synthesis including methodology mechanism formation. Applications also discussed, an outlook how push field forward discussed.

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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The Jehol Biota: Definition and distribution of exceptionally preserved relicts of a continental Early Cretaceous ecosystem

Cretaceous Research, Journal Year: 2013, Volume and Issue: 44, P. 30 - 38

Published: April 24, 2013

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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Prediction and Explanation in Historical Natural Science

The British Journal for the Philosophy of Science, Journal Year: 2011, Volume and Issue: 62(3), P. 551 - 582

Published: Feb. 27, 2011

In earlier work (Cleland [2001], [2002]), I sketched an account of the structure and justification ‘prototypical’ historical natural science that distinguishes it from ‘classical’ experimental science. This article expands upon this work, focusing close connection between explanation in sciences. argue confirmation disconfirmation these fields depends primarily explanatory (versus predictive or retrodictive) success failure hypotheses vis-à-vis empirical evidence. The develop is a version common cause explanation. Common has long been vindicated by appealing to principle cause. Many philosophers (e.g., Sober Tucker) find problematic, however, because they believe either purely methodological strictly metaphysical. defend third possibility: derives its physically pervasive time asymmetry causation (a.k.a. overdetermination). explicating terms overdetermination illuminates some otherwise puzzling features practices scientists. 1 Introduction2 Methodology Historical Natural Science3 Justification Science 3.1 Prediction 3.2 Adequate explanations are not potential predictions 3.3 centrality explanation4 Cause Explanation Asymmetry Overdetermination 4.1 priority over separate causes 4.2 threat information degrading processes

Language: Английский

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