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Pigment evolution

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https://www.readbyqxmd.com/read/28337898/melanin-of-the-nipple-areola-complex
#1
A Goren, M Kovacevic, T Lotti
Biological pigments or biochromes are ubiquitous in animals, plants, and simpler organisms such as fungi and bacteria. They serve a wide spectrum of functions from photosynthesis, camouflage, mimicry, photo protection from the environment to attracting mates. The human female nipple areola complex (NAC) is a highly-pigmented area. Currently, the prevailing theory as to the evolution of the pigmented human NAC is based on infant recognition of breast feeding latching zone; however, due to the protruding shape of the nipple and surrounding breast, the authors of this letter believe that the evolutionary advantage of the pigmented NAC has a direct physiological function, namely the initiation of involution at the end of the infant lactation period...
January 2017: Journal of Biological Regulators and Homeostatic Agents
https://www.readbyqxmd.com/read/28336284/macular-pigment-density-variation-after-supplementation-of-lutein-and-zeaxanthin-using-the-visucam-%C3%A2-200-pigment-module-impact-of-age-related-macular-degeneration-and-lens-status
#2
G Azar, M Quaranta-El Maftouhi, J-J Masella, M Mauget-Faÿsse
PURPOSE: To assess the evolution of macular pigment optical density (MPOD) following supplementation with various macular formulations obtained with the Visucam(®) 200, and to study the factors affecting MPOD measurements. MATERIALS AND METHODS: In this prospective, randomized, double-masked multicenter study, patients were divided into 2 groups: group A (patients without retinal pathology who underwent cataract surgery 1 month previously) and group B (patients with neovascular age-related macular degeneration [AMD] in one eye)...
March 20, 2017: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/28320315/comparative-transcriptome-analyses-of-flower-development-in-four-species-of-achimenes-gesneriaceae
#3
Wade R Roberts, Eric H Roalson
BACKGROUND: Flowers have an amazingly diverse display of colors and shapes, and these characteristics often vary significantly among closely related species. The evolution of diverse floral form can be thought of as an adaptive response to pollination and reproduction, but it can also be seen through the lens of morphological and developmental constraints. To explore these interactions, we use RNA-seq across species and development to investigate gene expression and sequence evolution as they relate to the evolution of the diverse flowers in a group of Neotropical plants native to Mexico-magic flowers (Achimenes, Gesneriaceae)...
March 20, 2017: BMC Genomics
https://www.readbyqxmd.com/read/28253223/observation-and-clinical-pattern-in-patients-with-white-dot-syndromes-the-role-of-color-photography-in-monitoring-ocular-changes-in-long-term-observation
#4
Joanna Brydak-Godowska, Joanna Gołębiewska, Monika Turczyńska, Joanna Moneta-Wielgoś, Agnieszka Samsel, Piotr K Borkowski, Michał Ciszek, Agnieszka Płonecka-Rodzoch, Aleksandra Kużnik-Borkowska, Joanna Ciszewska, Elżbieta Makomaska-Szaroszyk, Lidia B Brydak, Dariusz Kęcik
BACKGROUND The aim of this study was to assess the clinical course and distinctive features of different white dot syndromes (WDS) in patients attending the Ophthalmology Department, Medical University of Warsaw in the years 1995-2015. MATERIAL AND METHODS Sixty-two (62) patients (43 females and 19 males), aged 18 to 77 years, referred with a WDS were included in this prospective study, with observation period ranging from 5 months to 16 years. All patients underwent a complete ophthalmological examination and multimodal imaging studies...
March 2, 2017: Medical Science Monitor: International Medical Journal of Experimental and Clinical Research
https://www.readbyqxmd.com/read/28250185/epistatic-interactions-influence-terrestrial-marine-functional-shifts-in-cetacean-rhodopsin
#5
Sarah Z Dungan, Belinda S W Chang
Like many aquatic vertebrates, whales have blue-shifting spectral tuning substitutions in the dim-light visual pigment, rhodopsin, that are thought to increase photosensitivity in underwater environments. We have discovered that known spectral tuning substitutions also have surprising epistatic effects on another function of rhodopsin, the kinetic rates associated with light-activated intermediates. By using absorbance spectroscopy and fluorescence-based retinal release assays on heterologously expressed rhodopsin, we assessed both spectral and kinetic differences between cetaceans (killer whale) and terrestrial outgroups (hippo, bovine)...
March 15, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28248295/structure-of-the-plant-photosystem-i-supercomplex-at-2-6%C3%A2-%C3%A3-resolution
#6
Yuval Mazor, Anna Borovikova, Ido Caspy, Nathan Nelson
Four elaborate membrane complexes carry out the light reaction of oxygenic photosynthesis. Photosystem I (PSI) is one of two large reaction centres responsible for converting light photons into the chemical energy needed to sustain life. In the thylakoid membranes of plants, PSI is found together with its integral light-harvesting antenna, light-harvesting complex I (LHCI), in a membrane supercomplex containing hundreds of light-harvesting pigments. Here, we report the crystal structure of plant PSI-LHCI at 2...
March 1, 2017: Nature Plants
https://www.readbyqxmd.com/read/28246038/the-wheat-mutant-della-encoding-gene-rht-b1c-affects-plant-photosynthetic-responses-to-cadmium-stress
#7
Anelia G Dobrikova, Ekaterina K Yotsova, Andreas Börner, Svetlana P Landjeva, Emilia L Apostolova
Тhe sensitivity to cadmium (Cd) stress of two near-isogenic wheat lines with differences at the Rht-B1 locus, Rht-B1a (tall wild type, encoding DELLA proteins) and Rht-B1c (dwarf mutant, encoding modified DELLA proteins), was investigated. The effects of 100 μM CdCl2 on plant growth, pigment content and functional activity of the photosynthetic apparatus of wheat seedlings grown on a nutrient solution were evaluated through a combination of PAM chlorophyll fluorescence, oxygen evolution, oxidation-reduction kinetics of P700 and 77 K fluorescence...
February 20, 2017: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/28244868/lipid-droplet-biology-and-evolution-illuminated-by-the-characterization-of-a-novel-perilipin-in-teleost-fish
#8
James G Granneman, Vickie A Kimler, Huamei Zhang, Xiangqun Ye, Xixia Luo, John H Postlethwait, Ryan Thummel
Perilipin (PLIN) proteins constitute an ancient family important in lipid droplet (LD) formation and triglyceride metabolism. We identified an additional PLIN clade (plin6) that is unique to teleosts and can be traced to the two whole genome duplications that occurred early in vertebrate evolution. Plin6 is highly expressed in skin xanthophores, which mediate red/yellow pigmentation and trafficking, but not in tissues associated with lipid metabolism. Biochemical and immunochemical analyses demonstrate that zebrafish Plin6 protein targets the surface of pigment-containing carotenoid droplets (CD)...
February 28, 2017: ELife
https://www.readbyqxmd.com/read/28231253/community-analysis-of-pigment-patterns-from-37-microalgae-strains-reveals-new-carotenoids-and-porphyrins-characteristic-of-distinct-strains-and-taxonomic-groups
#9
Benoît Serive, Elodie Nicolau, Jean-Baptiste Bérard, Raymond Kaas, Virginie Pasquet, Laurent Picot, Jean-Paul Cadoret
Phytoplankton, with an estimated 30 000 to 1 000 000 species clustered in 12 phyla, presents a high taxonomic and ecophysiological diversity, reflected by the complex distribution of pigments among the different algal classes. High performance liquid chromatography is the gold standard method for qualitative and quantitative analysis of phytoplankton pigments in seawater and culture samples, but only a few pigments can be used as robust chemotaxonomic markers. A major challenge is thus to identify new ones, characteristic of a strain, species, class or taxon that cannot be currently identified on the basis of its pigment signature...
2017: PloS One
https://www.readbyqxmd.com/read/28230973/unique-optoelectronic-structure-and-photoreduction-properties-of-sulfur-doped-lead-chromates-explaining-their-instability-in-paintings
#10
Vanoushe Rahemi, Nasrin Sarmadian, Willemien Anaf, Koen Janssens, Dirk Lamoen, Bart Partoens, Karolien De Wael
Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artist's material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0 ≤ x ≤ 0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods...
March 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28228540/functional-optics-of-glossy-buttercup-flowers
#11
Casper J van der Kooi, J Theo M Elzenga, Jan Dijksterhuis, Doekele G Stavenga
Buttercup (Ranunculus spp.) flowers are exceptional because they feature a distinct gloss (mirror-like reflection) in addition to their matte-yellow coloration. We investigated the optical properties of yellow petals of several Ranunculus and related species using (micro)spectrophotometry and anatomical methods. The contribution of different petal structures to the overall visual signal was quantified using a recently developed optical model. We show that the coloration of glossy buttercup flowers is due to a rare combination of structural and pigmentary coloration...
February 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28197761/the-pigment-epithelium-derived-factor-pedf-an-important-potential-therapeutic-agent-for-infantile-hemangioma
#12
Ming Li, Yanru Chen, Zhihui Guo, Yide Xie, Yakuan Zhou, Chenghong Jiang, Xiaosong Chen
In previous studies, the expression and the role of proangiogenic factors in infantile hemangiomas have been well studied. However, the role of angiogenic inhibitors has been revealed rarely. The expression of PEDF, as the strongest and safe endogenous inhibitor, is still unrecognized until the current study. In order to investigate the expression and significance of the pigment epithelium-derived factor (PEDF) in the proliferating and regressing phases of infantile hemangiomas, the expression of PEDF, VEGF, Ki-67, and CD34 protein in hemangioma tissues was examined with immunohistochemical polymer HRP method in 42 cases during the proliferative phase, 40 cases during the regressing phase, and 11 cases of non-involuting congenital hemangiomas (NICHs)...
April 2017: Archives of Dermatological Research
https://www.readbyqxmd.com/read/28193726/genetic-basis-of-melanin-pigmentation-in-butterfly-wings
#13
Linlin Zhang, Arnaud Martin, Michael W Perry, Karin R L van der Burg, Yuji Matsuoka, Antónia Monteiro, Robert D Reed
Despite the variety, prominence, and adaptive significance of butterfly wing patterns surprisingly little known about the genetic basis of wing color diversity. Even though there is intense interest in wing pattern evolution and development, the technical challenge of genetically manipulating butterflies has slowed efforts to functionally characterize color pattern development genes. To identify candidate wing pigmentation genes we used RNA-seq to characterize transcription across multiple stages of butterfly wing development, and between different color pattern elements, in the painted lady butterfly Vanessa cardui This allowed us to pinpoint genes specifically associated with red and black pigment patterns...
February 13, 2017: Genetics
https://www.readbyqxmd.com/read/28187978/optical-coherence-tomography-examination-of-the-retinal-pigment-epithelium-in-best-vitelliform-macular-dystrophy
#14
Cynthia X Qian, Dionisio Charran, Cameron R Strong, Timothy J Steffens, Thiran Jayasundera, John R Heckenlively
PURPOSE: To describe the anatomic changes and natural history of vitelliform lesions in Best vitelliform macular dystrophy (BVMD) using spectral-domain optical coherence tomography (OCT). DESIGN: Prospective comparative case series. PARTICIPANTS: Twenty patients (40 eyes) with molecular confirmation of mutation in the BEST1 gene and 20 age-matched controls were included. METHODS: Color fundus photographs, fundus autofluorescence, and spectral-domain OCT were obtained, and these findings were compared between the 2 groups...
February 7, 2017: Ophthalmology
https://www.readbyqxmd.com/read/28176337/how-fish-color-their-skin-a-paradigm-for-development-and-evolution-of-adult-patterns-multipotency-plasticity-and-cell-competition-regulate-proliferation-and-spreading-of-pigment-cells-in-zebrafish-coloration
#15
Christiane Nüsslein-Volhard, Ajeet Pratap Singh
Pigment cells in zebrafish - melanophores, iridophores, and xanthophores - originate from neural crest-derived stem cells associated with the dorsal root ganglia of the peripheral nervous system. Clonal analysis indicates that these progenitors remain multipotent and plastic beyond embryogenesis well into metamorphosis, when the adult color pattern develops. Pigment cells share a lineage with neuronal cells of the peripheral nervous system; progenitors propagate along the spinal nerves. The proliferation of pigment cells is regulated by competitive interactions among cells of the same type...
March 2017: BioEssays: News and Reviews in Molecular, Cellular and Developmental Biology
https://www.readbyqxmd.com/read/28174022/the-evolution-and-genetics-of-carotenoid-processing-in-animals
#16
REVIEW
David P L Toews, Natalie R Hofmeister, Scott A Taylor
Coloration is one of the most conspicuous traits that varies among organisms. Carotenoid pigments are responsible for many of the red, orange, and yellow colors in the natural world and, at least for most animals, these molecules must be acquired from their environment. Identifying genes important for carotenoid transport, deposition, and processing has been difficult, in contrast to the well-characterized genes involved in the melanogenesis pathways. We review recent progress in the genetics of carotenoid processing, advances owing in part to the application of high-throughput sequencing data...
February 4, 2017: Trends in Genetics: TIG
https://www.readbyqxmd.com/read/28171723/reaction-kinetics-of-monomeric-anthocyanin-conversion-to-polymeric-pigment-and-significance-to-color-in-interspecific-hybrid-wines
#17
Claire E Burtch, Anna Katharine Mansfield, David C Manns
The color stability of red wines produced from interspecific hybrid grapes, which is partially dependent on anthocyanin diglucosides, is not well understood. In this study, the rate of decrease of monomeric anthocyanins as they polymerized to polymeric pigments due to the presence of excess catechin and acetaldehyde was measured in model wine using HPLC. Colorimetry was used to measure L*, a*, and b* values, hue angle, and change in color (∆E). Concentrations of individual diglucosides decreased more slowly than monoglucosides...
February 7, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28168103/in-situ-morphometric-survey-elucidates-the-evolutionary-systematics-of-the-eurasian-himantoglossum-clade-orchidaceae-orchidinae
#18
Richard M Bateman, Attila Molnár V, Gábor Sramkó
BACKGROUND AND AIMS: The charismatic Himantoglossum s.l. clade of Eurasian orchids contains an unusually large proportion of taxa that are of controversial circumscriptions and considerable conservation concern. Whereas our previously published study addressed the molecular phylogenetics and phylogeography of every named taxon within the clade, here we use detailed morphometric data obtained from the same populations to compare genotypes with associated phenotypes, in order to better explore taxonomic circumscription and character evolution within the clade...
2017: PeerJ
https://www.readbyqxmd.com/read/28168030/eggshell-coloration-and-its-importance-in-postmating-sexual-selection
#19
Miroslav Poláček, Matteo Griggio, Ivan Mikšík, Michaela Bartíková, Manfred Eckenfellner, Herbert Hoi
Avian eggshell color seems to fulfill multiple functions, some of them being structural and others signaling. In this study, we tested whether or not eggshell coloration may play a role in sexual selection of Tree Sparrows (Passer montanus). According to the "Sexually selected eggshell coloration" hypothesis, eggshell coloration signals female, egg or chick quality and males adjust parental investment according to this signal. Eggs of this species are covered with brown spots and patches, and variation between clutches is high...
February 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28166161/characterizing-photoreceptor-changes-in-acute-posterior-multifocal-placoid-pigment-epitheliopathy-using-adaptive-optics
#20
Philipp K Roberts, Peter L Nesper, Alex C Onishi, Dimitra Skondra, Lee M Jampol, Amani A Fawzi
PURPOSE: To characterize lesions of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) by multimodal imaging including adaptive optics scanning laser ophthalmoscopy (AOSLO). METHODS: We included patients with APMPPE at different stages of evolution of the placoid lesions. Color fundus photography, spectral domain optical coherence tomography, infrared reflectance, fundus autofluorescence, and AOSLO images were obtained and registered to correlate microstructural changes...
February 3, 2017: Retina
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