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Cell Reports Aug 2023A previously undescribed mechanism underlying butterfly wing coloration patterns was discovered in two distantly related butterfly species, Siproeta stelenes and...
A previously undescribed mechanism underlying butterfly wing coloration patterns was discovered in two distantly related butterfly species, Siproeta stelenes and Philaethria diatonica. These butterflies have bright green wings, but the color pattern is not derived from solid pigments or nanostructures of the scales or from the color of the cuticular membrane but rather from a liquid retained in the wing membrane. Wing structure differs between the green and non-green areas. In the non-green region, the upper and lower cuticular membranes are attached to each other, whereas in the green region, we observed a space of 5-10 μm where green liquid is held and living cells are present. A pigment analysis and tracer experiment revealed that the color of the liquid is derived from hemolymph components, bilin and carotenoid pigments. This discovery broadens our understanding of the diverse ways in which butterfly wings obtain their coloration and patterns.
Topics: Animals; Pigmentation; Butterflies; Wings, Animal; Membranes; Nanostructures
PubMed: 37537843
DOI: 10.1016/j.celrep.2023.112917 -
Nature Nov 2023
Topics: Flowers; Petunia; Pigmentation; Pigments, Biological; Research Personnel
PubMed: 37932556
DOI: 10.1038/d41586-023-03438-z -
Yi Chuan = Hereditas Feb 2021The various coat colorations exhibited in different mammalian groups is an attractive biological phenomenon, and is also one of the excellent models for studying and... (Review)
Review
The various coat colorations exhibited in different mammalian groups is an attractive biological phenomenon, and is also one of the excellent models for studying and understanding mammalian adaptive evolution. Coat color polymorphism in mammals plays an important role in avoiding predator, predation, courtship, and protection against UV radiation. The coloration of hair or coat in mammal is determined by the quantity, quality and distribution of melanin in the body. Pigmentation in cells is a complicated cell process, including the differentiation and maturation of melanocytes, the morphogenesis of melanosome, the anabolism of melanin and the transportation of melanin in melanocytes. Every stage or phase of pigmentation in cells can always proceed with the participation of some important functional genes. The complex regulatory network formed through interactions between these genes has greatly led to different coat colors. With the coat color polymorphisms, mammals can adapt to various environments. Revealing the genetic basis of different coat colors in mammals has been an important research focus in genetics and evolutionary biology. In this review, we summarize the main advance in molecular mechanisms of pigmentation in cells and the genetic basis of coloration-related adaptations in mammals. Our review is expected to provide new clues for molecular mechanism studies on coat color polymorphism and adaptive evolutions in mammals.
Topics: Animals; Color; Hair Color; Mammals; Melanins; Melanocytes; Pigmentation
PubMed: 33724215
DOI: 10.16288/j.yczz.20-390 -
Journal of Applied Microbiology Jul 2022The present review highlights the advantages of using natural colorant over the synthetic one. We have discussed the fermentation parameters that can enhance the... (Review)
Review
OBJECTIVE
The present review highlights the advantages of using natural colorant over the synthetic one. We have discussed the fermentation parameters that can enhance the productivity of Monascus pigment on agricultural wastes.
BACKGROUND
Food industry is looking for natural colours because these can enhance the esthetic value, attractiveness, and acceptability of food while remaining nontoxic. Many synthetic food colours (Azorubine Carmoisine, quinoline) have been prohibited due to their toxicity and carcinogenicity. Increasing consumer awareness towards the food safety has forced the manufacturing industries to look for suitable alternatives. In addition to safety, natural colorants have been found to have nutritional and therapeutic significance. Among the natural colorants, microbial pigments can be considered as a viable option because of scalability, easier production, no seasonal dependence, cheaper raw materials and easier extraction. Fungi such as Monascus have a long history of safety and therefore can be used for production of biopigments.
METHOD
The present review summarizes the predicted biosynthetic pathways and pigment gene clusters in Monascus purpureus.
RESULTS
The challenges faced during the pilot-scale production of Monascus biopigment and taming it by us of low-cost agro-industrial substrates for solid state fermentation has been suggested.
CONCLUSION
Keeping in mind, therapeutic properties of Monascus pigments and their derivatives, they have huge potential for industrial and pharmaceutical application.
APPLICATION
Though the natural pigments have wide scope in the food industry. However, stabilization of pigment is the greatest challenge and attempts are being made to overcome this by complexion with hydrocolloids or metals and by microencapsulation.
Topics: Fermentation; Monascus; Pigmentation; Pigments, Biological
PubMed: 34569683
DOI: 10.1111/jam.15308 -
Journal of the Mechanical Behavior of... Oct 2022This study aims to characterize the effect of pre- and/or post-sintering pigmentation techniques on the fatigue behavior of a 4YSZ ceramic (4 mol% yttrium stabilized...
This study aims to characterize the effect of pre- and/or post-sintering pigmentation techniques on the fatigue behavior of a 4YSZ ceramic (4 mol% yttrium stabilized zirconia). First, 4YSZ ceramic discs (IPS e.max ZirCAD, 15 mm diameter, and 1.2 mm thickness) were obtained and allocated according to the 'pigmentation technique' factor into 5 groups: Ctrl - unshaded ceramic disc (IPS e.max ZirCAD BL); Manuf - ceramic discs shaded by the manufacturer at block formation (IPS e.max ZirCAD MT A2); Brush - unshaded ceramic disc pigmented in the pre-sintered stage using a brush; Stain - unshaded ceramic disc pigmented in the post-sintering stage using a stain glaze (shade A2); Brush + Stain - combination of Brush and Stain techniques. The specimens were sintered and analyzed by a spectrophotometer (VITA Easyshade) for color differences (ΔE calculated according to CIEDE, 2000) to ensure that they present the same perceived color (ΔE ≤ 1.77, acceptability threshold). The specimens (n = 15) were submitted to biaxial flexural fatigue testing using a cyclic fatigue method (frequency of 20 Hz; 10,000 cycles per step; initial stress of 200 MPa; and step-size of 25 MPa) until specimen fracture. Fatigue strength (FS) and number of cycles until failure (CFF) were recorded with statistical purposes. Fractographic, complementary topography, elemental and roughness analyses were performed. The Ctrl shown the highest FS, CFF, and survival rates compared to the other conditions (p < 0.05), being only statistically similar to Brush. Stain showed the lowest FS, CFF and survival rates (p < 0.05). The Manuf and Brush + Stain shown intermediary performance. In regards of Weibull moduli, Brush shown the lowest values (lowest structural reliability), for both FS and CFF, being only statistically similar to Manuf. Topography analysis shown a uniform size of zirconia crystals in Ctrl, Manuf and Brush. In addition, a smooth glassy surface with some spots of impregnated pigment was observed in the groups where glaze was applied (Stain and Brush + Stain). This finding was corroborated by elemental analysis. Despite that, Stain and Brush + Stain presented the roughest surface (p < 0.05). In summary, the pigmentation techniques used to provide a Vita classical A2 color shade have a detrimental effect on the mechanical fatigue properties of a 4YSZ ceramic, except for the technique performed with the brush in the block pre-sintering stage. Despite this, the brush technique presents great variability in mechanical performance, resulting in lower structural reliability.
Topics: Ceramics; Dental Porcelain; Dental Stress Analysis; Materials Testing; Pigmentation; Reproducibility of Results; Surface Properties; Zirconium
PubMed: 35872462
DOI: 10.1016/j.jmbbm.2022.105362 -
American Journal of Clinical Dermatology Sep 2023As research related to skin of color (SOC) in dermatology continues to grow, it is increasingly important to precisely define terminology. The terms 'SOC', 'race', and...
As research related to skin of color (SOC) in dermatology continues to grow, it is increasingly important to precisely define terminology. The terms 'SOC', 'race', and 'ethnicity' are frequently used to analyze differences in dermatologic disease onset, severity, and outcomes. These terms are used interchangeably, are ill-defined across research studies, and frequently conflate biologic and socially constructed categories. SOC has been thought to represent differing degrees of pigment or melanin in the skin, however skin pigment is quite variable among races and ethnicities. Furthermore, certain individuals with less skin pigment may socially consider themselves to be SOC, while the inverse is also true. Fitzpatrick skin phototype classifications in SOC dermatology, while commonly used as an objective measure of diversity, also present with numerous limitations and inaccuracies. We seek to highlight strengths and weaknesses of the current terminology used in SOC dermatology and recommend a more holistic understanding of reported differences, including a framework reflective of upstream socioeconomic, environmental, and historical factors that may be most relevant to reported associations.
Topics: Humans; Dermatology; Ethnicity; Pigmentation Disorders; Skin; Skin Pigmentation; Racial Groups
PubMed: 37328613
DOI: 10.1007/s40257-023-00800-9 -
Yi Chuan = Hereditas Jun 2022Sexually dimorphic plumage coloration is widespread in birds in which the male plumage is brighter than the female. This phenomenon is related to the environmental... (Review)
Review
Sexually dimorphic plumage coloration is widespread in birds in which the male plumage is brighter than the female. This phenomenon is related to the environmental constraints on sexual selection or intraspecific competition between males and females in birds. The physiological factors and genetic regulation mechanism affecting the color of sexual dimorphism plumages in birds have always attracted significant attention in research. Understanding the diversity of sexually dimorphic traits provides insights into the mating strategies of the sexes and their behavior, ecology, and evolution. Interestingly, the ASIP, MC1R, TYRP1, and BCO2 genes have been identified to play a potential role in the coloration of melanin and carotenoids in bird sexual dimorphism plumages, either by controlling the rate and type of melanin or carotene synthesis or degradation by exerting an effect on the pigment biosynthetic pathway. In this review, we systematically summarize the biological significance, the direct causes (chemical and physical color), and the influence of sex hormones in sexually dimorphic plumage coloration. We also investigate the molecular mechanism underlying the roles of some genes on sexual dimorphism coloration, thereby providing a reference for in-depth understanding on the formation mechanism(s) of sexual dimorphic coloration in birds.
Topics: Animals; Birds; Color; Feathers; Female; Male; Melanins; Pigmentation; Sex Characteristics
PubMed: 35729097
DOI: 10.16288/j.yczz.22-004 -
Photochemistry and Photobiology Jan 2021Optical properties of plant leaves are relevant to evaluate their physiological state and stress effect. The main objective of this work was to study how variegation,...
Optical properties of plant leaves are relevant to evaluate their physiological state and stress effect. The main objective of this work was to study how variegation, pigment composition or reflective features modifies leaves' photophysical behavior. For this purpose, green leaves (Ficus benjamina), purple leaves (Tradescantia pallida), green leaves covered by white trichomes (Cineraria maritima) and variegated leaves (Codiaeum aucubifolium) were analyzed. Firstly, foliar surface morphology was evaluated by scanning electron microscopy. UV-vis and near-IR reflectance and transmittance spectra were obtained to calculate absorption (k) and scattering (s) coefficients. The theoretical approaches of Pile of Plates and Kubelka-Munk's theory resulted still valid for nonstandard leaves with differing surface conditions. However, frequently used spectral indices were not reliable for predicting water content, when leaves differed from conventional ones. The proportionality between the absorption factor and chromophore/pigment concentration was also lost for hairy leaves. A simplified model to describe these facts was presented here. Fluorescence spectra were recorded and corrected, due to light re-absorption. Water-optical parameter connection and pigment-optical parameter connection were thoroughly discussed. Leaf surface morphology and pigmentation have not only influenced the optical features of leaves but also played a role in the effect that particulate matter could cause on leaf photosynthesis.
Topics: Fluorescence; Light; Particulate Matter; Pigmentation; Plant Leaves; Plants; Species Specificity; Surface Properties
PubMed: 32297341
DOI: 10.1111/php.13273 -
Journal of Molecular Biology Nov 2019Phenotypic heterogeneity in bacterial cell populations allows genetically identical organisms to different behavior under similar environmental conditions. The... (Review)
Review
Phenotypic heterogeneity in bacterial cell populations allows genetically identical organisms to different behavior under similar environmental conditions. The Gram-negative bacterium Photorhabdus luminescens is an excellent organism to study phenotypic heterogeneity since their life cycle involves a symbiotic interaction with soil nematodes as well as a pathogenic association with insect larvae. Phenotypic heterogeneity is highly distinct in P. luminescens. The bacteria exist in two phenotypic forms that differ in various morphologic and phenotypic traits and are therefore distinguished as primary (1°) and secondary (2°) cells. The 1 cells are bioluminescent, pigmented, produce several secondary metabolites and exo-enzymes, and support nematode growth and development. The 2° cells lack all these 1°-specific phenotypes. The entomopathogenic nematodes carry 1° cells in their upper gut and release them into an insect's body after slipping inside. During insect infection, up to the half number of 1° cells undergo phenotypic switching and convert to 2° cells. Since the 2° cells are not able to live in nematode symbiosis any more, they cannot re-associate with their symbiosis partners after the infection and remain in the soil. Phenotypic switching in P. luminescens has to be tightly regulated since a high switching frequency would lead to a complete break-down of the nematode-bacteria life cycle. Here, we present the main regulatory mechanisms known to-date that are important for phenotypic switching in P. luminescens cell populations and discuss the biological reason as well as the fate of the 2° cells in the soil.
Topics: Bacterial Physiological Phenomena; Bacterial Proteins; Biological Variation, Population; Gene Expression Regulation, Bacterial; Life Cycle Stages; Phenotype; Photorhabdus; Pigmentation; Quorum Sensing; Symbiosis
PubMed: 31022406
DOI: 10.1016/j.jmb.2019.04.015 -
Nature Reviews. Genetics Aug 2020Coloration is an easily quantifiable visual trait that has proven to be a highly tractable system for genetic analysis and for studying adaptive evolution. The... (Review)
Review
Coloration is an easily quantifiable visual trait that has proven to be a highly tractable system for genetic analysis and for studying adaptive evolution. The application of genomic approaches to evolutionary studies of coloration is providing new insight into the genetic architectures underlying colour traits, including the importance of large-effect mutations and supergenes, the role of development in shaping genetic variation and the origins of adaptive variation, which often involves adaptive introgression. Improved knowledge of the genetic basis of traits can facilitate field studies of natural selection and sexual selection, making it possible for strong selection and its influence on the genome to be demonstrated in wild populations.
Topics: Adaptation, Biological; Animals; Biological Evolution; Genetic Variation; Genome; Genomics; Multifactorial Inheritance; Mutation; Phenotype; Pigmentation; Pigments, Biological; Quantitative Trait Loci; Quantitative Trait, Heritable; Selection, Genetic
PubMed: 32382123
DOI: 10.1038/s41576-020-0234-z