Article
Biochemistry & Molecular Biology
Claire E. Meyer, Cora-Ann Schoenenberger, Riccardo P. Wehr, Dalin Wu, Cornelia G. Palivan
Summary: By mimicking the confinement of natural melanin in melanosomes, melanosome mimics containing melanin/polydopamine within polymersomes are developed, showing long-term colloidal stability, cell-compatibility, and potential for cell photoprotection. This novel artificial melanogenesis is expected to inspire new applications of confined melanin/polydopamine biopolymers.
MACROMOLECULAR BIOSCIENCE
(2021)
Article
Geology
Nathan Barling, Farid Saleh, Xiaoya Ma
Summary: A study has revealed the existence of in situ prokaryote fossils preserved alongside macrofossils in the Crato Formation of Brazil, highlighting the unique diagenetic and paleoenvironmental conditions that facilitated this mode of fossilization.
Article
Geochemistry & Geophysics
Farid Saleh, Orla G. Bath-Enright, Allison C. Daley, Bertrand Lefebvre, Bernard Pittet, Antoine Vite, Xiaoya Ma, M. Gabriela Mangano, Luis A. Buatois, Jonathan B. Antcliffe
Summary: Understanding the functioning of extinct ecosystems is a complex task that involves ecological, evolutionary, and preservational factors. By developing a novel method of data partitioning based on probabilistic modelling for the Walcott Quarry in Canada and the Fezouata Shale in Morocco, researchers were able to reveal differences in soft-tissue preservation mechanisms and ecological selectivity. This study highlights the importance of calibrating exceptional fossil sites to comprehend evolutionary events and the ecological structuring of ancient animal communities during the Cambrian Explosion and Ordovician Radiation.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Food Science & Technology
Wen Song, Rong-e Xing, Haoyue Yang, Song Liu, Pengcheng Li
Summary: This study compared the extraction methods of alkali-assisted and enzyme-assisted extraction of eumelanin, finding that the enzyme-assisted extraction had higher yield and purity than alkali-assisted extraction. Eumelanin exhibited significant inhibitory effects on alpha-glycosidase enzyme and alpha-amylase activity, promoting glucose utilization in cells and increasing hepatic glycogen synthesis.
JOURNAL OF FOOD PROCESSING AND PRESERVATION
(2021)
Article
Biology
Mary Higby Schweitzer, Wenxia Zheng, Nancy Equall
Summary: This study experimentally investigates the effects of burial/exposure, sediment type, the addition of feather-degrading microbes, and minerals on feather preservation, and compares these effects in different CO2 atmospheres. The results suggest that the elevated CO2 levels in the Mesozoic may have contributed to the preservation of feathers by promoting rapid precipitation of hydroxy- or carbonate hydroxyapatite and stabilizing organic components.
Article
Biochemistry & Molecular Biology
Alexander E. Dontsov, Marina A. Yakovleva, Alexander A. Vasin, Alexander A. Gulin, Arseny V. Aybush, Viktor A. Nadtochenko, Mikhail A. Ostrovsky
Summary: The aging process in the human eye leads to a decrease in melanosomes in retinal pigment epithelium (RPE) cells. This decrease can result in the development of age-related pathologies and various retinal diseases. Previous research has shown that oxidative degradation of melanin by superoxide radicals leads to the formation of water-soluble fluorescent products. In this study, it was demonstrated that visible light irradiation on melanolipofuscin granules isolated from RPE cells in the human eye also resulted in the formation of these products, while lipofuscin granules and melanosomes did not show the same reaction. The decrease in melanin concentration in RPE cells is attributed to its oxidative degradation by reactive oxygen species generated by lipofuscin under the action of light.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biology
Brandt M. Gibson, James D. Schiffbauer, Adam F. Wallace, Simon A. F. Darroch
Summary: In this study, the role of iron in the preservation of Ediacaran organisms is characterized through decay experiments. The results demonstrate that iron can contribute to the formation of death masks, but other factors such as tissue histology and the availability of nucleation sites also play a significant role. This suggests that Ediacaran preservation through microbial death masks can occur under a range of conditions, rather than being solely dependent on the abundance of iron.
Article
Biology
Caitlin Colleary, Shane O'Reilly, Andrei Dolocan, Jason G. Toyoda, Rosalie K. Chu, Malak M. Tfaily, Michael F. Hochella, Sterling J. Nesbitt
Summary: This article discusses the differences in preservation at different scales in fossils and analyzes them using mass spectrometry techniques. The results show that high-quality macro-scale preservation does not necessarily predict the preservation of biomolecules.
Article
Multidisciplinary Sciences
Valentin de Mazancourt, Torsten Wappler, Sonja Wedmann
Summary: A new species of extinct freshwater shrimp has been discovered in the Eocene deposit. This rare find includes several specimens, one of which has remarkably preserved soft tissues and other internal parts. By examining the characteristics of the shrimp, researchers can gain insights into its morphology and its role in the ancient ecosystem. Another specimen shows slightly different morphology and may belong to a different species.
SCIENTIFIC REPORTS
(2022)
Article
Geology
Neil S. Davies, Anthony P. Shillito
Summary: The paper discusses the presence of true substrates in the sedimentary-stratigraphic record, which are preserved surfaces that existed at the sediment-water or sediment-air interface at the time of deposition. These surfaces provide valuable palaeoenvironmental information and reveal fossilized snapshots of microscale topography from deep time.
Article
Environmental Sciences
Laura Sanchez-Garcia, Maria Angeles Lezcano, Daniel Carrizo, Rita Severino, Miriam Garcia-Villadangos, Sherry L. Cady, Kim Warren-Rhodes, Nathalie A. Cabrol, Victor Parro
Summary: Subaerial hydrothermal systems are potential environments for the origin of life on Earth and Mars, offering a unique atmosphere-hydrosphere-lithosphere interface. The sinter deposits in these systems are promising targets for searching extraterrestrial life signs. This study investigates the effects of silicification on the preservation of lipid biomarkers using samples from El Tatio. The data reveals the degradation rate of lipid biomarkers and informs the time window for recovering signs of past life.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Biochemistry & Molecular Biology
Deivid Franca Freitas, Izabelli Martins da Rocha, Olney Vieira-da-Motta, Clovis de Paula Santos
Summary: Melanin is a heteropolymer formed by the polymerization of phenolic and indolic compounds, with various protective advantages such as against ultraviolet radiation, traumatic damage, oxidative stress, extreme temperatures, and pressure. In many fungi, melanin plays a direct role in pathogenicity, with the ability to synthesize it in different ways, either endogenously with 1,8-dihydroxynaphthalene (DHN) or exogenously with L-3, 4-dihydroxyphenylalanine (L-DOPA). The complex and amorphous nature of melanin makes it challenging to study with conventional biochemical techniques, especially in nematophagous fungi which are still poorly understood.
JOURNAL OF CHEMICAL ECOLOGY
(2021)
Article
Dermatology
Yoko Niki, Naoko Adachi, Masaki Fukata, Yuko Fukata, Shinichiro Oku, Chieko Makino-Okamura, Seiji Takeuchi, Kazumasa Wakamatsu, Shosuke Ito, Lieve Declercq, Daniel B. Yarosh, Tomas Mammone, Chikako Nishigori, Naoaki Saito, Takehiko Ueyama
Summary: This study found that by inhibiting the degradation of tyrosinase, the rate-limiting enzyme in melanin synthesis, an increase in melanin content and tyrosinase protein levels can be achieved in melano-genic cells. The palmitoylation site of tyrosinase was identified as Cys500, and the DHHC2, DHHC3, and DHHC15 proteins were found to be involved in tyrosinase palmitoylation. These findings suggest that palmitoylation plays an important role in regulating melanogenesis by controlling the protein levels of tyrosinase.
JOURNAL OF INVESTIGATIVE DERMATOLOGY
(2023)
Article
Multidisciplinary Sciences
Ratheesh K. Meleppat, Kaitryn E. Ronning, Sarah J. Karlen, Marie E. Burns, Edward N. Pugh, Robert J. Zawadzki
Summary: This study investigated disease-related changes in the density of melanosomes and lipofuscin granules in retinal pigment epithelium cells using an in vivo multimodal imaging technique. The results indicated an increased concentration of lipofuscin granules and decreased concentration of melanosomes in the RPE of Abca4(-/-) mice, a model of Stargardt disease.
SCIENTIFIC REPORTS
(2021)
Article
Geosciences, Multidisciplinary
Farid Saleh, Romain Vaucher, Jonathan B. Antcliffe, Allison C. Daley, Khadija El Hariri, Khaoula Kouraiss, Bertrand Lefebvre, Emmanuel L. O. Martin, Jean-Philippe Perrillat, Pierre Sansjofre, Muriel Vidal, Bernard Pittet
Summary: The Fezouata Biota in Morocco is a unique Lower Ordovician Lagerstadtte, preserving a diverse biological assemblage with organisms typical of Cambrian Burgess Shale-type ecosystems. Most organisms were already dead and decaying on the seafloor before being buried by occasional storm-induced deposits. The non-preservation of completely cellular organisms like jellyfish in the Fezouata Shale is attributed to pre-burial decay. Despite preservation biases, the autochthonous assemblages offer a unique opportunity to understand Early Palaeozoic seas compared to other Cambrian BST biotas.
EARTH-SCIENCE REVIEWS
(2021)
Article
Biology
Christophe Hendrickx, Phil R. Bell, Michael Pittman, Andrew R. C. Milner, Elena Cuesta, Jingmai O'Connor, Mark Loewen, Philip J. Currie, Octavio Mateus, Thomas G. Kaye, Rafael Delcourt
Summary: Non-avialan theropods exhibit diverse skin structures, including scales, naked skin, and dermal ossifications, but limited preservation of skin on most specimens hinders further investigation. Reticulate scales are ubiquitous in footprints of these dinosaurs, suggesting a consistent pattern of tiny scales on the plantar surface of their feet.
BIOLOGICAL REVIEWS
(2022)
Article
Biochemistry & Molecular Biology
Waisum Ma, Michael Pittman, Richard J. Butler, Stephan Lautenschlager
Summary: Theropod dinosaurs underwent significant changes in their mandibular evolution and morphological adaptations, which reflected their dietary shifts. Using finite element analysis, we found variations in feeding mechanics among different dietary groups and major clades of non-avialan coelurosaurian theropods. Overall, there was a reduction in feeding-induced stresses along all theropod lineages through time. This reduction was associated with the expansion and development of the mandible in herbivores and carnivores, likely through the curved bone effect. Observing the same reduction in an ontogenetic series of jaws in tyrannosaurids, we suggest that this structural strengthening of the theropod mandible over time, regardless of diet, is linked to functional adaptations acquired during ontogeny.
Article
Biology
Michael Pittman, Nathan J. Enriquez, Phil R. Bell, Thomas G. Kaye, Paul Upchurch
Summary: The discovery of Haestasaurus becklesii's scaly skin in 1852 played a crucial role in the study of dinosaur integument and has now been reassessed using Laser-Stimulated Fluorescence (LSF) to reveal previously unknown regions of skin. This reassessment provides new insights into the morphology and taphonomy of the dinosaur skin, suggesting an Early Jurassic origin of unique intrascale papillae and their potential role in gigantism evolution.
COMMUNICATIONS BIOLOGY
(2022)
Article
Biology
Case Vincent Miller, Michael Pittman, Xiaoli Wang, Xiaoting Zheng, Jen A. Bright
Summary: This study investigates the diet of extinct birds by using four different proxies to determine their feeding habits. By studying the characteristics of extant birds and applying them to the longipterygid birds, the researchers were able to reveal the diet types and behaviors of these extinct birds.
Article
Multidisciplinary Sciences
Michael Pittman, Thomas G. Kaye, Hebert B. Campos, Michael B. Habib
Summary: This study analyzes well-preserved specimens of pterosaurs from Solnhofen to demonstrate that quadrupedal water launch was feasible in these animals, and that webbed feet played a significant role in launch performance. Additionally, the study identifies three key factors that limit water launch performance in all pterosaurs.
SCIENTIFIC REPORTS
(2022)
Article
Archaeology
Michael Pittman, Thomas G. Kaye, Elizabeth Graham, David Thorold
Summary: Laser-stimulated fluorescence (LSF) is a non-destructive imaging technique that has diverse applications in archaeology, including revealing hidden soft tissues in fossils, analyzing ancient production processes, assisting in excavation and conservation, and identifying large-scale and hard-to-reach objects.
JOURNAL OF ARCHAEOLOGICAL SCIENCE-REPORTS
(2022)
Article
Biology
Phil R. Bell, Christophe Hendrickx, Michael Pittman, Thomas G. Kaye
Summary: Researchers have discovered the oldest preserved umbilicus in a fossil of an early branching ceratopsian dinosaur, Psittacosaurus, dating back to approximately 130 million years ago. This finding suggests that the umbilicus was likely retained by the dinosaur until sexual maturity.
Article
Biology
Phil R. Bell, Christophe Hendrickx, Michael Pittman, Thomas G. Kaye, Gerald Mayr
Summary: Laser-stimulated fluorescence imaging reveals new insights into the skin anatomy and function of Psittacosaurus, a member of the ceratopsian dinosaur group. The study identifies variations in the squamous skin of Psittacosaurus, including unique features and previously unknown integumentary structures. The examination also reveals crocodylian-like internal anatomy in the cloaca of Psittacosaurus. The findings, combined with a comprehensive review of integument in ceratopsian dinosaurs, contribute to a better understanding of the complexity of scalation in these dinosaurs.
COMMUNICATIONS BIOLOGY
(2022)
Correction
Biology
Arindam Roy, Michael Pittman, Thomas G. Kaye, Evan T. Saitta, Xing Xu
BIOLOGICAL REVIEWS
(2023)
Article
Multidisciplinary Sciences
Michael Pittman, Thomas G. Kaye, Xiaoli Wang, Xiaoting Zheng, T. Alexander Dececchi, Scott A. Hartman
Summary: This study reveals the soft anatomy of the earliest flying theropod dinosaurs, providing evidence for the existence of an ancestral flight system and offering insights into novel flight strokes and early sternum loss.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Psychology, Experimental
Matthew W. Lowder, Antonio Cardoso, Michael Pittman, Adrian Zhou
Summary: Previous research has shown that the difficulty of processing complex semantic expressions is influenced by sentence structure. This study aimed to investigate how changes in sentence structure affect the processing of lexical repetition. The results indicate that repetition priming effects are stronger when repetition occurs across clause boundaries compared to within a clause, and that the felicity of the repetition plays a role in this effect.
MEMORY & COGNITION
(2023)
Article
Biodiversity Conservation
Arindam Roy, Michael Pittman, Thomas G. Kaye, Evan T. Saitta
Summary: Melanin pigments play a central role in the colors and patterns of modern vertebrate integuments, providing insights into ecological and behavioral strategies. Recent research has shown that melanin can be used to predict color in well-preserved fossil feathers of dinosaurs and birds. However, more studies are needed to understand the stability of melanin and its chemical changes during diagenesis, and how they impact paleocolor reconstruction.