Chemical Evaluation of Eumelanin Maturation by ToF-SIMS and Alkaline Peroxide Oxidation HPLC Analysis

International Journal of Molecular Sciences, Journal Year: 2020, Volume and Issue: 22(1), P. 161 - 161

Published: Dec. 26, 2020

Residual melanins have been detected in multimillion-year-old animal body fossils; however, confident identification and characterization of these natural pigments remain challenging due to loss chemical signatures during diagenesis. Here, we simulate this post-burial process through artificial maturation experiments using three synthetic one eumelanin exposed mild (100 °C/100 bar) harsh (250 °C/200 environmental conditions, followed by analysis employing alkaline hydrogen peroxide oxidation (AHPO) time-of-flight secondary ion mass spectrometry (ToF-SIMS). Our results show that AHPO is sensitive changes the melanin molecular structure already heat pressure treatment (resulting, e.g., increased C-C cross-linking), whereas leads extensive eumelanin-specific markers. In contrast, negative-ion ToF-SIMS spectra are considerably less affected features even after treatment. Detailed acquired prior experimental revealed significant differences between investigated eumelanins. However, systematic spectral upon reduced dissimilarities, indicating intense formation a common, partially degraded, structure. findings elucidate complementary nature traces fossilized organismal remains.

Language: Английский

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Skin patterning and internal anatomy in a fossil moonfish from the Eocene Bolca Lagerstätte illuminate the ecology of ancient reef fish communities

Palaeontology, Journal Year: 2022, Volume and Issue: 65(3)

Published: May 1, 2022

Abstract Colour patterning in extant animals can be used as a reliable indicator of their biology and, fish, inform on feeding strategy. Fossil fish with preserved colour patterns may thus illuminate the evolution behaviour and community structure, but are understudied. Here we report melanin‐based integumentary internal anatomy fossil moonfish Mene rhombea (Menidae) from Bolca Lagerstätte (Eocene (Ypresian), north‐east Italy). The melanosome‐based longitudinal stripes M . differ dorsal rows black spots its relative maculata , suggesting that ecology has changed during Cenozoic. Extant coastal schooling feed benthic invertebrates, stomach contents remains suggest unstructured open marine ecologies piscivorous diet. localized distribution species Indo‐Pacific Ocean reflect, at least part, tectonically‐driven reorganization global oceanographic It is likely shifts habitat genes promoted pattern menid lineage.

Language: Английский

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Thymosin β4 Identified by Transcriptomic Analysis from HF Anagen to Telogen Promotes Proliferation of SHF-DPCs in Albas Cashmere Goat

International Journal of Molecular Sciences, Journal Year: 2020, Volume and Issue: 21(7), P. 2268 - 2268

Published: March 25, 2020

Increasing cashmere yield is one of the important goals goat breeding. To achieve this goal, we screened key genes that can improve performance. In study, used RNA raw datasets skin and dermal papilla cells secondary hair follicle (SHF-DPCs) samples (HF) anagen telogen Albas goats identified a set significant differentially expressed (DEGs). explore potential associations between gene sets SHF growth features to identify candidate genes, detected functional enrichment constructed protein-protein interaction (PPI) networks. Through comprehensive analysis, selected Thymosin β4 (Tβ4), Rho GTPase activating protein 6 (ARHGAP6), ADAM metallopeptidase with thrombospondin type 1 motif 15, (ADAMTS15), Chordin (CHRD), SPARC (Osteonectin), cwcv kazal-like domains proteoglycan (SPOCK1) as genes. Gene analysis (GSEA) for these revealed Tβ4 ARHGAP6 have close association development SHF-DPCs. However, expression in was higher than telogen, so finally chose ultimate research object. Overexpressing promoted silencing inhibited proliferation These findings suggest promote SHF-DPCs indicate molecule may be valuable target increasing production.

Language: Английский

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Petrological Meaning of Ethnostratigraphic Units: Laminated Limestone of the Crato Formation, Araripe Basin, NE Brazil

Pesquisas em Geociências, Journal Year: 2022, Volume and Issue: 49(1), P. e121139 - e121139

Published: July 25, 2022

Crato Formation, NE Brazil, consists of laminated limestones deposited in a lacustrine environment during the Early Cretaceous. The Nova Olinda Member, lowest unit is world-famous for their exceptionally well-preserved fossils. have been economically exploited centuries. Today, this commercial excavation still represents main economic activity region. During mining process, quarry workers developed an informal stratigraphic code to individualize different beds quarries. Upward, local recognize succession as “lajão dos sete cortes”, “matracão", branco", “pão de milho”, “veio da paiba”, "veio doidão”, amarelo” and do besouro”. Here, we used principles ethnostratigraphy verify origin validity these nomenclatures by classifying them ethnostra. For this, applied detailed petrographical analysis with thin sections high-resolution X-ray techniques characterize each ethnostratum. Our results suggest possible linkages between formal Member. Finally, study showed that can be auxiliary tool studies, both, initial exploratory approach enhancing relationship geologists community.

Language: Английский

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Sediment-encased pressure–temperature maturation experiments elucidate the impact of diagenesis on melanin-based fossil color and its paleobiological implications

Paleobiology, Journal Year: 2023, Volume and Issue: 49(4), P. 712 - 732

Published: May 8, 2023

Abstract Melanin pigments are central to colors and patterns in modern vertebrate integuments, which inform upon ecological behavioral strategies like crypsis, aposematism, sociosexual selection. Over the last decade, melanin has emerged as a valuable tool for predicting color exceptionally preserved fossil feathers subsequent testing of paleobiological hypotheses long-extinct dinosaurs birds. Yet much remains be learned about stability, diagenetic alterations chemistry, their implications “paleocolor reconstruction.” Pressure–temperature maturation experiments with offer way examine these topics but have mostly been conducted closed-system capsules or open-system aluminum foil. Both methods operational limitations do not consider filtering effect porous sediment matrices on thermally labile chemical groups versus stable ones during natural fossilization. We use sediment-encased resolve this issue demonstrate replication organic preservation highly comparable compression fossils. Our experiments, coupled time-of-flight secondary ion mass spectrometry, show predictable volatilization N/S-bearing molecules increased cross-linking elevated temperatures. also suggest that eumelanin is more compared pheomelanin at higher temperatures, explaining why eumelanic (black, dark brown, iridescent) better fossils than pheomelanic (reddish brown). Furthermore, we propose proteins preferentially undergo hydrolysis so forming N-heterocycles selectively open systems analogous matrices. Thus, conclude diagenetically altered protein remnants key players promoting fossilization soft tissues feathers.

Language: Английский

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Fluorescent colour patterns in the basal pectinid Pleuronectites from the Middle Triassic of Central Europe: origin, fate and taxonomic implications of fluorescence

Palaeontology, Journal Year: 2022, Volume and Issue: 65(5)

Published: Sept. 1, 2022

Abstract UV light‐induced fluorescence is widely used as a key to reveal residual shell colour patterns of Neogene and Palaeogene molluscs. However, only few examples fluorescent are known from Mesozoic marine shells little about the nature in fossils. Here, reveals previously unseen abundance diversity basal pectinid Pleuronectites laevigatus Middle Triassic Muschelkalk Central Europe. In addition variations radial bands, multitude zigzag zigzag‐related was found. The comparable modern pectinids interpreted pattern polymorphism. Raman spectra indicated preservation organic pigments with aromatic moieties. properties P. other Germany France described detail, suggesting that due colourless diagenetic products pigments, not fossil themselves. A remarkable feature presence different colours. Because gradual shift yellow red decreasing intensity finally non‐fluorescent observed, which correlates provenance specimens, reflect differences history. results show molluscs, especially may be affected by diagenesis should caution for taxonomic purposes.

Language: Английский

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毛发的梯度成熟实验对化石毛发的埋藏学启示

SCIENTIA SINICA Terrae, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 1, 2024

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Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

Science China Earth Sciences, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 29, 2024

Language: Английский

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EDITORIAL NOTE: Collection of Paleontology Papers in honor of the Centenary of the Brazilian Academy of Sciences

Anais da Academia Brasileira de Ciências, Journal Year: 2019, Volume and Issue: 91(suppl 2)

Published: Jan. 1, 2019

The Brazilian Academy of Sciences is a non-profit organization (ABC

Language: Английский

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Melanins

Encyclopedia of Astrobiology, Journal Year: 2023, Volume and Issue: unknown, P. 1838 - 1844

Published: Jan. 1, 2023

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