Reptiles Produce Pheomelanin: Evidence in the Eastern Hermann's Tortoise (<i>Eurotestudo boettgeri</i>)

Roulin, Alexandre; Mafli, Alia; Wakamatsu, Kazumasa

doi:10.1670/12-028

Cited by 27 publications

(19 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Phaeomelanin was thought to be restricted to warm-blooded animals, presumably evolving convergently for metabolic reasons (40). However, it appears that phaeomelanin is actually more widespread in ectothermic organisms than previously thought (14)(15)(16)(17). As proposed recently (20), the more pure melanins in mammals and birds could reflect the marked shift in external integument with the evolution of hair and feathers for insulation in these warm-blooded animals rather than physiology (13).…”

Section: Melanosome Shrinkage During Burial Diagenesis and Maturationmentioning

confidence: 88%

“…In extant mammals and birds, eumelanosomes are oblong, with a higher aspect ratio than phaeomelanosomes, which are smaller and more spherical (3,13). It is not clear whether other amniotes or fishes produce morphologically distinct melanosomes, but chemical evidence distinguishes pure eumelanin and phaeomelanin in turtles (14), and phaeomelanin has been tentatively reported in frogs (15), fish (16), and chitons (Mollusca) (17). Melanosome morphology currently serves as the primary basis for interpretations of fossil feather color, as it correlates with several distinct melaninbased colors and iridescence in modern birds (1,3,4).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils

Colleary

Dolocan²,

Gardner

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

107

170

View full text Add to dashboard Cite

In living organisms, color patterns, behavior, and ecology are closely linked. Thus, detection of fossil pigments may permit inferences about important aspects of ancient animal ecology and evolution. Melanin-bearing melanosomes were suggested to preserve as organic residues in exceptionally preserved fossils, retaining distinct morphology that is associated with aspects of original color patterns. Nevertheless, these oblong and spherical structures have also been identified as fossilized bacteria. To date, chemical studies have not directly considered the effects of diagenesis on melanin preservation, and how this may influence its identification. Here we use time-of-flight secondary ion mass spectrometry to identify and chemically characterize melanin in a diverse sample of previously unstudied extant and fossil taxa, including fossils with notably different diagenetic histories and geologic ages. We document signatures consistent with melanin preservation in fossils ranging from feathers, to mammals, to amphibians. Using principal component analyses, we characterize putative mixtures of eumelanin and phaeomelanin in both fossil and extant samples. Surprisingly, both extant and fossil amphibians generally exhibit melanosomes with a mixed eumelanin/phaeomelanin composition rather than pure eumelanin, as assumed previously. We argue that experimental maturation of modern melanin samples replicates diagenetic chemical alteration of melanin observed in fossils. This refutes the hypothesis that such fossil microbodies could be bacteria, and demonstrates that melanin is widely responsible for the organic soft tissue outlines in vertebrates found at exceptional fossil localities, thus allowing for the reconstruction of certain aspects of original pigment patterns.

show abstract

Section: Melanosome Shrinkage During Burial Diagenesis and Maturationmentioning

confidence: 88%

mentioning

confidence: 99%

Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils

Colleary

Dolocan²,

Gardner

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

107

170

View full text Add to dashboard Cite

show abstract

“…chemical characterization procedures, it has been shown that pheomelanins can also occur in reptiles [50] but they are still very rare in lower organisms. Occurrence of pheomelanin was claimed in fungi [51] but the only criteria to propose that presence was the yellowish color of the fungal obtained pigments, without chemical analysis.…”

Section: Animal Melaninsmentioning

confidence: 99%

“…Hormonal control of melanization by MSH (melanin stimulating hormone) is also important in these animals, as well as birds and mammals, but this point is out of the scope of this review. Melanins in these animals are generally eumelanin, although some report on the presence of pheomelanin in tortoise has been recently published [50]. These animals have an active extracutaneous pigmentary system, so that melanin is also found in blood phagocytic cells [78], peritoneum, liver, and kidney [79][80][81] although the role of the pigment in those tissues is not well understood.…”

Section: Animal Melaninsmentioning

confidence: 99%

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

Solano

2014

New Journal of Science

443

431

View full text Add to dashboard Cite

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

show abstract

“…Eumelanic and pheomelanic traits are generally associated with specific colours: the former being responsible for black and grey colours and the latter for yellowish, reddish, and brown ones (Toral, Figuerola & Negro, 2008;Galv an & Møller, 2011). Although reptiles were assumed to produce only eumelanin (Ito & Wakamatsu, 2003), recently Roulin, Mafli & Wakamatsu (2013) were able to demonstrate their capacity to produce pheomelanin too. However, we use the terms brownish and yellowish coloration because pheomelanin production in lizards has not yet been confirmed.…”

Section: Dorsal Colorationmentioning

confidence: 99%

Dorsal pattern polymorphism in female Iberian wall lizards: differences in morphology, dorsal coloration, immune response, and reproductive investment

Ortega

Pellitteri‐Rosa

López

et al. 2015

Biol. J. Linn. Soc.

View full text Add to dashboard Cite

Sex-specific colour polymorphisms have been extensively documented in many different taxa. When polymorphism in colour pattern is restricted to females, the condition is known as female-limited pattern polymorphism (FPP), which has been less commonly addressed in vertebrates. FPP is present in several lizard species, although most research on lizards has focused on carotenoid-and pteridine-based coloration and not on melanin-based polymorphisms. In the present study, we focus on Iberian wall lizards, Podarcis hispanicus, where two female melanin-based dorsal patterns can be clearly distinguished: striped and reticulated-blotched. We indirectly tested the hypothesis that selection acts differentially among P. hispanicus female morphs to create alternative morph-specific phenotypic optima at different levels by investigating whether morphs differ in fitness proxies. We specifically examined whether the two female dorsal pattern morphs differed in adult morphology, dorsal coloration, immune response, reproductive investment, and growth. We did not find a relationship between melanin-based coloration and hatchling growth and immune response, despite a correlation between these traits possibly being expected as a result of pleiotropy in the melanocortin system. However, our results show that female dorsal morphs in P. hispanicus differ in terms of adult morphology, dorsal coloration, and reproductive investment. Reticulated-blotched P. hispanicus females had deeper heads and longer femora, less melanin, and more brownish coloration, and also had larger and heavier hatchlings than striped females.

show abstract

Reptiles Produce Pheomelanin: Evidence in the Eastern Hermann's Tortoise (Eurotestudo boettgeri)

Cited by 27 publications

References 33 publications

Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils

Chemical, experimental, and morphological evidence for diagenetically altered melanin in exceptionally preserved fossils

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

Dorsal pattern polymorphism in female Iberian wall lizards: differences in morphology, dorsal coloration, immune response, and reproductive investment

Contact Info

Product

Resources

About