True bursal pigmented villonodular synovitis

Energy Technology Data Exchange (ETDEWEB)

Abdelwahab, Ibrahim Fikry [Department of Radiology, New York Methodist Hospital, Affiliated with New York Hospital-Cornell Medical Center, Brooklyn, NY (United States); Kenan, Samuel [Department of Orthopedics, New York University Medical Center, NY (United States); Steiner, German C. [Department of Pathology, Hospital for Joint Diseases/Orthopedic Institute, New York, NY (United States); Abdul-Quader, Mohammed [Department of Radiology, New York Presbyterian Hospital, Columbia University, New York, NY (United States)

2002-06-01

We describe two cases of pigmented villonodular synovitis affecting true bursae. This study was also designed to discuss the term ''pigmented villonodular bursitis'', not confined to true synovial bursae, sometimes creating misunderstanding. (orig.)

Internal and external factors affecting photosynthetic pigment composition in plants: a meta-analytical approach.

Science.gov (United States)

Esteban, Raquel; Barrutia, Oihana; Artetxe, Unai; Fernández-Marín, Beatriz; Hernández, Antonio; García-Plazaola, José Ignacio

2015-04-01

Photosynthetic pigment composition has been a major study target in plant ecophysiology during the last three decades. Although more than 2000 papers have been published, a comprehensive evaluation of the responses of photosynthetic pigment composition to environmental conditions is not yet available. After an extensive survey, we compiled data from 525 papers including 809 species (subkingdom Viridiplantae) in which pigment composition was described. A meta-analysis was then conducted to assess the ranges of photosynthetic pigment content. Calculated frequency distributions of pigments were compared with those expected from the theoretical pigment composition. Responses to environmental factors were also analysed. The results revealed that lutein and xanthophyll cycle pigments (VAZ) were highly responsive to the environment, emphasizing the high phenotypic plasticity of VAZ, whereas neoxanthin was very stable. The present meta-analysis supports the existence of relatively narrow limits for pigment ratios and also supports the presence of a pool of free 'unbound' VAZ. Results from this study provide highly reliable ranges of photosynthetic pigment contents as a framework for future research on plant pigments. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Gibberellin requirement for Arabidopsis seed germination is determined both by testa characteristics and embryonic abscisic acid

NARCIS (Netherlands)

Debeaujon, I.; Koornneef, M.

2000-01-01

The mechanisms imposing a gibberellin (GA) requirement to promote the germination of dormant and non-dormant Arabidopsis seeds were analyzed using the GA-deficient mutant ga1, several seed coat pigmentation and structure mutants, and the abscisic acid (ABA)-deficient mutant aba1. Testa mutants,

Pigmented skin disorders: Evaluation and treatment

NARCIS (Netherlands)

Kroon, M.W.

2015-01-01

Pigmentary disorders are disturbances of human skin color. Minor changes in the cellular physiology of the skin can dramatically affect pigment production in positive or negative manner. In this these, associated diseases, therapeutical options and disease parameters for the pigmentation disorder

Biochemical responses and ultrastructural changes in ethylene insensitive mutants of Arabidopsis thialiana subjected to bisphenol A exposure.

Science.gov (United States)

Ali, Imran; Jan, Mehmood; Wakeel, Abdul; Azizullah, Azizullah; Liu, Bohan; Islam, Faisal; Ali, Abid; Daud, M K; Liu, Yihua; Gan, Yinbo

2017-10-01

Bisphenol A (BPA), an important raw material in plastic industry, has become a serious environmental contaminant due to its wide spread use in different products and increasing release into the environment. BPA is known to cause adverse effects in living organisms including plants. Several studies reported that BPA affects growth and development in plants, mainly through oxidative stress. Plants are known to generally cope with stress mainly through hormonal regulation and adaptation, but little is known about the role of plant hormones in plants under BPA stress. The present study was conducted to investigate the role of ethylene in BPA induced oxidative stress in plants using Arabidopsis thaliana as a test plant. The response of ethylene insensitive mutants of Arabidopsis (ein2-1 and etr1-3) to BPA exposure was studied in comparison to the wild type Arabidopsis (WT). In all three genotypes, exposure to BPA adversely affected cellular structures, stomata and light-harvesting pigments. An increase in reactive oxygen species (ROS) lipid peroxidation and other oxidative stress markers indicated that BPA induced toxicity through oxidative stress. However, the overall results revealed that WT Arabidopsis had more pronounced BPA induced damages while ein2-1 and etr1-3 mutants withstood the BPA induced stress more efficiently. The activity of antioxidant enzymes and expression of antioxidants related genes revealed that the antioxidant defense system in both mutants was more efficiently activated than in WT against BPA induced oxidative stress, which further evidenced the involvement of ethylene in regulating BPA induced oxidative stress. It is concluded that ethylene perception and signaling may be involved in BPA induced oxidative stress responses in plants. Copyright © 2017 Elsevier Inc. All rights reserved.

A mutation in the aroE gene affects pigment production, virulence, and chemotaxis in Xanthomonas oryzae pv. oryzae.

Science.gov (United States)

Kim, Hong-Il; Noh, Tae-Hwan; Lee, Chang-Soo; Park, Young-Jin

2015-01-01

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB) in rice. To study its function, a random insertion mutation library of Xoo was constructed using the Tn5 transposon. A mutant strain with decreased virulence against the susceptible rice cultivar IR24 was isolated from the library (aroE mutant), which also had extremely low pigment production. Thermal asymmetric interlaced-polymerase chain reaction (TAIL-PCR) and sequence analysis of the mutant revealed that the transposon was inserted into the aroE gene (encoding shikimate dehydrogenase). To investigate gene expression changes in the pigment- and virulence-deficient mutant, DNA microarray analysis was performed, which showed downregulation of 20 genes involved in the chemotaxis of Xoo. Our findings reveal that mutation of the aroE gene affects virulence and pigment production, as well as expression of genes involved in Xoo chemotaxis. Copyright © 2014 Elsevier GmbH. All rights reserved.

The FRIABLE1 gene product affects cell adhesion in Arabidopsis.

Directory of Open Access Journals (Sweden)

Lutz Neumetzler

Full Text Available Cell adhesion in plants is mediated predominantly by pectins, a group of complex cell wall associated polysaccharides. An Arabidopsis mutant, friable1 (frb1, was identified through a screen of T-DNA insertion lines that exhibited defective cell adhesion. Interestingly, the frb1 plants displayed both cell and organ dissociations and also ectopic defects in organ separation. The FRB1 gene encodes a Golgi-localized, plant specific protein with only weak sequence similarities to known proteins (DUF246. Unlike other cell adhesion deficient mutants, frb1 mutants do not have reduced levels of adhesion related cell wall polymers, such as pectins. Instead, FRB1 affects the abundance of galactose- and arabinose-containing oligosaccharides in the Golgi. Furthermore, frb1 mutants displayed alteration in pectin methylesterification, cell wall associated extensins and xyloglucan microstructure. We propose that abnormal FRB1 action has pleiotropic consequences on wall architecture, affecting both the extensin and pectin matrices, with consequent changes to the biomechanical properties of the wall and middle lamella, thereby influencing cell-cell adhesion.

Light-induced vegetative anthocyanin pigmentation in Petunia

OpenAIRE

Albert, Nick W.; Lewis, David H.; Zhang, Huaibi; Irving, Louis J.; Jameson, Paula E.; Davies, Kevin M.

2009-01-01

The Lc petunia system, which displays enhanced, light-induced vegetative pigmentation, was used to investigate how high light affects anthocyanin biosynthesis, and to assess the effects of anthocyanin pigmentation upon photosynthesis. Lc petunia plants displayed intense purple anthocyanin pigmentation throughout the leaves and stems when grown under high-light conditions, yet remain acyanic when grown under shade conditions. The coloured phenotypes matched with an accumulation of anthocyanins...

Arabidopsis AtPAP1 transcription factor induces anthocyanin production in transgenic Taraxacum brevicorniculatum.

Science.gov (United States)

Qiu, Jian; Sun, Shuquan; Luo, Shiqiao; Zhang, Jichuan; Xiao, Xianzhou; Zhang, Liqun; Wang, Feng; Liu, Shizhong

2014-04-01

This study developed a new purple coloured Taraxacum brevicorniculatum plant through genetic transformation using the Arabidopsis AtPAP1 gene, which overproduced anthocyanins in its vegetative tissues. Rubber-producing Taraxacum plants synthesise high-quality natural rubber (NR) in their roots and so are a promising alternative global source of this raw material. A major factor in its commercialization is the need for multipurpose exploitation of the whole plant. To add value to the aerial tissues, red/purple plants of the rubber-producing Taraxacum brevicorniculatum species were developed through heterologous expression of the production of anthocyanin pigment 1 (AtPAP1) transcription factor from Arabidopsis thaliana. The vegetative tissue of the transgenic plants showed an average of a 48-fold increase in total anthocyanin content over control levels, but with the exception of pigmentation, the transgenic plants were phenotypically comparable to controls and displayed similar growth vigor. Southern blot analysis confirmed that the AtPAP1 gene had been integrated into the genome of the high anthocyanin Taraxacum plants. The AtPAP1 expression levels were estimated by quantitative real-time PCR and were highly correlated with the levels of total anthocyanins in five independent transgenic lines. High levels of three cyanidin glycosides found in the purple plants were characterized by high performance liquid chromatography-mass spectrum analysis. The presence of NR was verified by NMR and infrared spectroscopy, and confirmed that NR biosynthesis had not been affected in the transgenic Taraxacum lines. In addition, other major phenylpropanoid products such as chlorogenic acid and quercetin glycosides were also enhanced in the transgenic Taraxacum. The red/purple transgenic Taraxacum lines described in this study would increase the future application of the species as a rubber-producing crop due to its additional health benefits.

Expression of the sweetpotato R2R3-type IbMYB1a gene induces anthocyanin accumulation in Arabidopsis.

Science.gov (United States)

Chu, Hyosub; Jeong, Jae Cheol; Kim, Wook-Jin; Chung, Dong Min; Jeon, Hyo Kon; Ahn, Young Ock; Kim, Sun Ha; Lee, Haeng-Soon; Kwak, Sang-Soo; Kim, Cha Young

2013-06-01

R2R3-type MYB transcription factors (TFs) play important roles in transcriptional regulation of anthocyanins. The R2R3-type IbMYB1 is known to be a key regulator of anthocyanin biosynthesis in the storage roots of sweetpotato. We previously showed that transient expression of IbMYB1a led to anthocyanin pigmentation in tobacco leaves. In this article, we generated transgenic Arabidopsis plants expressing the IbMYB1a gene under the control of CaMV 35S promoter, and the sweetpotato SPO and SWPA2 promoters. Overexpression of IbMYBa in transgenic Arabidopsis produced strong anthocyanin pigmentation in seedlings and generated a deep purple color in leaves, stems and seeds. Reverse transcription-polymerase chain reaction analysis showed that IbMYB1a expression induced upregulation of several structural genes in the anthocyanin biosynthetic pathway, including 4CL, CHI, F3'H, DFR, AGT, AAT and GST. Furthermore, overexpression of IbMYB1a led to enhanced expression of the AtTT8 (bHLH) and PAP1/AtMYB75 genes. high-performance liquid chromatography analysis revealed that IbMYB1a expression led to the production of cyanidin as a major core molecule of anthocyanidins in Arabidopsis, as occurs in the purple leaves of sweetpotato (cv. Sinzami). This result shows that the IbMYB1a TF is sufficient to induce anthocyanin accumulation in seedlings, leaves, stems and seeds of Arabidopsis plants. Copyright © Physiologia Plantarum 2012.

The penetration depth and lateral distribution of pigment related to the pigment grain size and the calendering of paper

International Nuclear Information System (INIS)

Buelow, K.; Kristiansson, P.; Schueler, B.; Tullander, E.; Oestling, S.; Elfman, M.; Malmqvist, K.; Pallon, J.; Shariff, A.

2002-01-01

The interaction of ink and newspaper has been investigated and the specific question of penetration of ink into the paper has been addressed with a nuclear microprobe using particle induced X-ray emission. The penetration depth of the newsprint is a critical factor in terms of increasing the quality of newsprint and minimising the amount of ink used. The objective of the experiment was to relate the penetration depth of pigment with the calendering of the paper. The dependence of the penetration depth on the pigment grain size was also studied. To study the penetration depth of pigment in paper, cyan ink with Cu as a tracer of the coloured pigment was used. For the study of the penetration depth dependence of pigment size, specially grounded Japanese ink with well-defined pigment grain size was used. This was compared to Swedish ink with pigment grains with normal size-distribution. The results show that the calendering of the paper considerably affects the penetration depth of ink

A near-null magnetic field affects cryptochrome-related hypocotyl growth and flowering in Arabidopsis

Science.gov (United States)

Xu, Chunxiao; Yin, Xiao; Lv, Yan; Wu, Changzhe; Zhang, Yuxia; Song, Tao

2012-03-01

The blue light receptor, cryptochrome, has been suggested to act as a magnetoreceptor based on the proposition that photochemical reactions are involved in sensing the geomagnetic field. But the effects of the geomagnetic field on cryptochrome remain unclear. Although the functions of cryptochrome have been well demonstrated for Arabidopsis, the effect of the geomagnetic field on the growth of Arabidopsis and its mechanism of action are poorly understood. We eliminated the local geomagnetic field to grow Arabidopsis in a near-null magnetic field and found that the inhibition of Arabidopsis hypocotyl growth by white light was weakened, and flowering time was delayed. The expressions of three cryptochrome-signaling-related genes, PHYB, CO and FT also changed; the transcript level of PHYB was elevated ca. 40%, and that of CO and FT was reduced ca. 40% and 50%, respectively. These data suggest that the effects of a near-null magnetic field on Arabidopsis are cryptochrome-related, which may be revealed by a modification of the active state of cryptochrome and the subsequent signaling cascade.

Herbivore-induced resistance against microbial pathogens in Arabidopsis

NARCIS (Netherlands)

Vos, de M.; Zaanen, van W.; Koornneef, A.; Korzelius, J.P.; Dicke, M.; Loon, van L.C.; Pieterse, C.M.J.

2006-01-01

Caterpillars of the herbivore Pieris rapae stimulate the production of jasmonic acid (JA) and ethylene (ET) in Arabidopsis (Arabidopsis thaliana) and trigger a defense response that affects insect performance on systemic tissues. To investigate the spectrum of effectiveness of P. rapae-induced

Herbivore-induced resistance against microbial pathogens in Arabidopsis

NARCIS (Netherlands)

Vos, M. de; Zaanen, W. van; Koornneef, A.; Korzelius, J.P.; Dicke, M.; Loon, L.C. van; Pieterse, C.M.J.

2006-01-01

Caterpillars of the herbivore Pieris rapae stimulate the production of jasmonic acid (JA) and ethylene (ET) in Arabidopsis (Arabidopsis thaliana) and trigger a defense response that affects insect performance on systemic tissues. To investigate the sspectrum of effectiveness of P. rapae-induced

Regulation of the anthocyanin biosynthetic pathway by the TTG1/bHLH/Myb transcriptional complex in Arabidopsis seedlings.

Science.gov (United States)

Gonzalez, Antonio; Zhao, Mingzhe; Leavitt, John M; Lloyd, Alan M

2008-03-01

In all higher plants studied to date, the anthocyanin pigment pathway is regulated by a suite of transcription factors that include Myb, bHLH and WD-repeat proteins. However, in Arabidopsis thaliana, the Myb regulators remain to be conclusively identified, and little is known about anthocyanin pathway regulation by TTG1-dependent transcriptional complexes. Previous overexpression of the PAP1 Myb suggested that genes from the entire phenylpropanoid pathway are targets of regulation by Myb/bHLH/WD-repeat complexes in Arabidopsis, in contrast to other plants. Here we demonstrate that overexpression of Myb113 or Myb114 results in substantial increases in pigment production similar to those previously seen as a result of over-expression of PAP1, and pigment production in these overexpressors remains TTG1- and bHLH-dependent. Also, plants harboring an RNAi construct targeting PAP1 and three Myb candidates (PAP2, Myb113 and Myb114) showed downregulated Myb gene expression and obvious anthocyanin deficiencies. Correlated with these anthocyanin deficiencies is downregulation of the same late anthocyanin structural genes that are downregulated in ttg1 and bHLH anthocyanin mutants. Expression studies using GL3:GR and TTG1:GR fusions revealed direct regulation of the late biosynthetic genes only. Functional diversification between GL3 and EGL3 with regard to activation of gene targets was revealed by GL3:GR studies in single and double bHLH mutant seedlings. Expression profiles for Myb and bHLH regulators are also presented in the context of pigment production in young seedlings.

Sinapate esters provide greater UV-B attenuation than flavonoids in Arabidopsis thaliana (Brassicaceae)

International Nuclear Information System (INIS)

Sheahan, J.J.

1996-01-01

Mutants affected in flavonoid (tt4) or sinapate ester (fah1) biosynthesis were used to assess the relative importance of these phenolic UV photoprotectants in Arabidopsis. Flavonoid and sinapate ester absorption was more specific for UV-B than major nonphenolic chromophores in crude extracts. A new method of evaluating phenolic UV-B attenuation was developed using fluorescence analysis. When excited by UV-B, sinapate ester containing leaves and cotyledons had enhanced sinapate ester fluorescence and reduced chlorophyll fluorescence relative to those without sinapate esters. Although fluorescence analysis gave no evidence of UV-B attenuation by flavonoids, enhanced chlorophyll and protein loss were observed upon UV-B exposure in flavonoid-deficient leaves, suggesting they have another mechanism of UV-B protection. The hydroxycinnamates have been largely ignored as UV-B attenuating pigments. and the results indicate that greater attention should be paid to their role in attenuating UV-B

Effect of pigment concentration on fastness and color values of thermal and UV curable pigment printing

Science.gov (United States)

Baysal, Gulcin; Kalav, Berdan; Karagüzel Kayaoğlu, Burçak

2017-10-01

In the current study, it is aimed to determine the effect of pigment concentration on fastness and colour values of thermal and ultraviolet (UV) curable pigment printing on synthetic leather. For this purpose, thermal curable solvent-based and UV curable water-based formulations were prepared with different pigment concentrations (3, 5 and 7%) separately and applied by screen printing technique using a screen printing machine. Samples printed with solvent-based formulations were thermally cured and samples printed with water-based formulations were cured using a UV curing machine equipped with gallium and mercury (Ga/Hg) lamps at room temperature. The crock fastness values of samples printed with solvent-based formulations showed that increase in pigment concentration was not effective on both dry and wet crock fastness values. On the other hand, in samples printed with UV curable water-based formulations, dry crock fastness was improved and evaluated as very good for all pigment concentrations. However, increasing the pigment concentration affected the wet crock fastness values adversely and lower values were observed. As the energy level increased for each irradiation source, the fastness values were improved. In comparison with samples printed with solvent-based formulations, samples printed with UV curable water-based formulations yielded higher K/S values at all pigment concentrations. The results suggested that, higher K/S values can be obtained in samples printed with UV curable water-based formulations at a lower pigment concentration compared to samples printed with solvent-based formulations.

The Arabidopsis Transcription Factor MYB112 Promotes Anthocyanin Formation during Salinity and under High Light Stress.

Science.gov (United States)

Lotkowska, Magda E; Tohge, Takayuki; Fernie, Alisdair R; Xue, Gang-Ping; Balazadeh, Salma; Mueller-Roeber, Bernd

2015-11-01

MYB transcription factors (TFs) are important regulators of flavonoid biosynthesis in plants. Here, we report MYB112 as a formerly unknown regulator of anthocyanin accumulation in Arabidopsis (Arabidopsis thaliana). Expression profiling after chemically induced overexpression of MYB112 identified 28 up- and 28 down-regulated genes 5 h after inducer treatment, including MYB7 and MYB32, which are both induced. In addition, upon extended induction, MYB112 also positively affects the expression of PRODUCTION OF ANTHOCYANIN PIGMENT1, a key TF of anthocyanin biosynthesis, but acts negatively toward MYB12 and MYB111, which both control flavonol biosynthesis. MYB112 binds to an 8-bp DNA fragment containing the core sequence (A/T/G)(A/C)CC(A/T)(A/G/T)(A/C)(T/C). By electrophoretic mobility shift assay and chromatin immunoprecipitation coupled to quantitative polymerase chain reaction, we show that MYB112 binds in vitro and in vivo to MYB7 and MYB32 promoters, revealing them as direct downstream target genes. We further show that MYB112 expression is up-regulated by salinity and high light stress, environmental parameters that both require the MYB112 TF for anthocyanin accumulation under these stresses. In contrast to several other MYB TFs affecting anthocyanin biosynthesis, MYB112 expression is not controlled by nitrogen limitation or an excess of carbon. Thus, MYB112 constitutes a regulator that promotes anthocyanin accumulation under abiotic stress conditions. © 2015 American Society of Plant Biologists. All Rights Reserved.

Skin flora: Differences between people affected by Albinism and those with normally pigmented skin in Northern Tanzania - cross sectional study.

Science.gov (United States)

Kiprono, Samson K; Masenga, John E; Chaula, Baraka M; Naafs, Bernard

2012-07-30

Skin flora varies from one site of the body to another. Individual's health, age and gender determine the type and the density of skin flora. A 1  cm² of the skin on the sternum was rubbed with sterile cotton swab socked in 0.9% normal saline and plated on blood agar. This was cultured at 35 °C. The bacteria were identified by culturing on MacConkey agar, coagulase test, catalase test and gram staining. Swabs were obtained from 66 individuals affected by albinism and 31 individuals with normal skin pigmentation. Those with normal skin were either relatives or staying with the individuals affected by albinism who were recruited for the study. The mean age of the 97 recruited individuals was 30.6 (SD ± 14.9) years. The mean of the colony forming units was 1580.5 per cm2. Those affected by albinism had a significantly higher mean colony forming units (1680  CFU per cm²) as compared with 453.5  CFU per cm² in those with normally pigmented skin (p = 0.023). The skin type and the severity of sun- damaged skin was significantly associated with a higher number of colony forming units (p = 0.038). Individuals affected by albinism have a higher number of colony forming units which is associated with sun- damaged skin.

Characterization of xanthophyll pigments, photosynthetic performance, photon energy dissipation, reactive oxygen species generation and carbon isotope discrimination during artemisinin-induced stress in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

M Iftikhar Hussain

Full Text Available Artemisinin, a potent antimalarial drug, is phytotoxic to many crops and weeds. The effects of artemisinin on stress markers, including fluorescence parameters, photosystem II photochemistry, photon energy dissipation, lipid peroxidation, reactive oxygen species generation and carbon isotope discrimination in Arabidopsis thaliana were studied. Arabidopsis ecotype Columbia (Col-0 seedlings were grown in perlite and watered with 50% Hoagland nutrient solution. Adult plants of Arabidopsis were treated with artemisinin at 0, 40, 80, 160 μM for one week. Artemisinin, in the range 40-160 μM, decreased the fresh biomass, chl a, b and leaf mineral contents. Photosynthetic efficiency, yield and electron transport rate in Arabidopsis were also reduced following exposure to 80 and 160 μM artemisinin. The ΦNPQ and NPQ were less than control. Artemisinin treatment caused an increase in root oxidizability and lipid peroxidation (MDA contents of Arabidopsis. Calcium and nitrogen contents decreased after 80 and 160 μM artemisinin treatment compared to control. δ13C values were less negative following treatment with artemisinin as compared to the control. Artemisinin also decreased leaf protein contents in Arabidopsis. Taken together, these data suggest that artemisinin inhibits many physiological and biochemical processes in Arabidopsis.

TEM studies of the crystal growth of indanthrone pigments

International Nuclear Information System (INIS)

McHendry, P.

1998-01-01

The aim of this work was to study the crystal growth of indanthrone during the pigmentation process. The colouring properties of a pigment are dependant on the chemical and crystallographic structure of the pigment. However, other factors are known to affect these properties including particle size, particle size distribution and level of dispersion in the chosen application medium. The parameters which affect the growth of the pigment particles were investigated with the emphasis placed on the mechanism by which growth took place. The final form of the crystals after growth was also investigated in some detail. Various electron microscopy techniques were employed in the investigations in this thesis. High and low magnification imaging and diffraction were studied on the CTEM (conventional transmission electron microscope) whilst PEELS (parallel electron energy loss spectroscopy) and DPC (differential phase contrast) studies took place on the VG HB5 STEM (scanning transmission electron microscope). In addition to these studies, x-ray diffraction and surface area analysis techniques were employed. The low magnification CTEM work gave good information on the size, shape and size distribution of the pigment particles and enabled detailed analysis of the level of growth attained under varied reaction conditions. (author)

The Arabidopsis Transcription Factor MYB112 Promotes Anthocyanin Formation during Salinity and under High Light Stress1[OPEN

Science.gov (United States)

Lotkowska, Magda E.; Tohge, Takayuki; Fernie, Alisdair R.; Xue, Gang-Ping; Balazadeh, Salma; Mueller-Roeber, Bernd

2015-01-01

MYB transcription factors (TFs) are important regulators of flavonoid biosynthesis in plants. Here, we report MYB112 as a formerly unknown regulator of anthocyanin accumulation in Arabidopsis (Arabidopsis thaliana). Expression profiling after chemically induced overexpression of MYB112 identified 28 up- and 28 down-regulated genes 5 h after inducer treatment, including MYB7 and MYB32, which are both induced. In addition, upon extended induction, MYB112 also positively affects the expression of PRODUCTION OF ANTHOCYANIN PIGMENT1, a key TF of anthocyanin biosynthesis, but acts negatively toward MYB12 and MYB111, which both control flavonol biosynthesis. MYB112 binds to an 8-bp DNA fragment containing the core sequence (A/T/G)(A/C)CC(A/T)(A/G/T)(A/C)(T/C). By electrophoretic mobility shift assay and chromatin immunoprecipitation coupled to quantitative polymerase chain reaction, we show that MYB112 binds in vitro and in vivo to MYB7 and MYB32 promoters, revealing them as direct downstream target genes. We further show that MYB112 expression is up-regulated by salinity and high light stress, environmental parameters that both require the MYB112 TF for anthocyanin accumulation under these stresses. In contrast to several other MYB TFs affecting anthocyanin biosynthesis, MYB112 expression is not controlled by nitrogen limitation or an excess of carbon. Thus, MYB112 constitutes a regulator that promotes anthocyanin accumulation under abiotic stress conditions. PMID:26378103

Candida glabrata tryptophan-based pigment production via the Ehrlich pathway.

Science.gov (United States)

Brunke, Sascha; Seider, Katja; Almeida, Ricardo Sergio; Heyken, Antje; Fleck, Christian Benjamin; Brock, Matthias; Barz, Dagmar; Rupp, Steffen; Hube, Bernhard

2010-04-01

Pigments contribute to the pathogenicity of many fungi, mainly by protecting fungal cells from host defence activities. Here, we have dissected the biosynthetic pathway of a tryptophan-derived pigment of the human pathogen Candida glabrata, identified key genes involved in pigment production and have begun to elucidate the possible biological function of the pigment. Using transcriptional analyses and a transposon insertion library, we have identified genes associated with pigment production. Targeted deletion mutants revealed that the pigment is a by-product of the Ehrlich pathway of tryptophan degradation: a mutant lacking a tryptophan-upregulated aromatic aminotransferase (Aro8) displayed significantly reduced pigmentation and a recombinantly expressed version of this protein was sufficient for pigment production in vitro. Pigment production is tightly regulated as the synthesis is affected by the presence of alternative nitrogen sources, carbon sources, cyclic AMP and oxygen. Growth of C. glabrata on pigment inducing medium leads to an increased resistance to hydrogen peroxide, an effect which was not observed with a mutant defective in pigmentation. Furthermore, pigmented yeast cells had a higher survival rate when exposed to human neutrophils and caused increased damage in a monolayer model of human epithelia, indicating a possible role of pigmentation during interactions with host cells.

Small molecule screening identifies targetable zebrafish pigmentation pathways

DEFF Research Database (Denmark)

Colanesi, Sarah; Taylor, Kerrie L; Temperley, Nicholas D

2012-01-01

Small molecules complement genetic mutants and can be used to probe pigment cell biology by inhibiting specific proteins or pathways. Here, we present the results of a screen of active compounds for those that affect the processes of melanocyte and iridophore development in zebrafish and investig......Small molecules complement genetic mutants and can be used to probe pigment cell biology by inhibiting specific proteins or pathways. Here, we present the results of a screen of active compounds for those that affect the processes of melanocyte and iridophore development in zebrafish...... and investigate the effects of a few of these compounds in further detail. We identified and confirmed 57 compounds that altered pigment cell patterning, number, survival, or differentiation. Additional tissue targets and toxicity of small molecules are also discussed. Given that the majority of cell types...

The acyl-CoA binding protein affects Monascus pigment production in Monascus ruber CICC41233.

Science.gov (United States)

Long, Chuannan; Liu, Mengmeng; Chen, Xia; Wang, Xiaofang; Ai, Mingqiang; Cui, Jingjing; Zeng, Bin

2018-02-01

The present study verified whether acyl-coenzyme A (acyl-CoA)-binding protein (ACBP) affected the production of Monascus pigments (MPs) in Monascus ruber CICC41233 (MrACBP). Phylogenetic analysis revealed that the cloned Mracbp gene, which encoded the MrACBP protein, exhibited the closest match (99% confidence level) to the gene from Penicilliopsis zonata . The MrACBP and maltose-binding protein (MBP) were simultaneously expressed in Escherichia coli Rosetta DE3 in the form of a fusion protein. The microscale thermophoresis binding assay revealed that the purified MBP-MrACBP exhibited a higher affinity for myristoyl-CoA (Kd = 88.16 nM) than for palmitoyl-CoA (Kd = 136.07 nM) and octanoyl-CoA (Kd = 270.9 nM). Further, the Mracbp gene was homologously overexpressed in M. ruber CICC41233, and a positive transformant M. ruber ACBP5 was isolated. The fatty acid myristic acid in M. ruber ACBP5 was lower than that in the parent strain M. ruber CICC41233. However, when compared with the parent strain, the production of total MPs, water-soluble pigment, and ethanol-soluble pigment in M. ruber ACBP5 increased by 11.67, 9.80, and 12.70%, respectively, after 6 days. The relative gene expression level, as determined by a quantitative real-time polymerase chain reaction analysis, of the key genes acbp , pks , mppr1 , fasA , and fasB increased by 4.03-, 3.58-, 1.67-, 2.11-, and 2.62-fold after 6 days. These data demonstrate the binding preference of MrACBP for myristoyl-CoA, and its influence on MPs production.

Strictly NO3- Nutrition Alleviates Iron Deficiency Chlorosis in Arabidopsis thaliana Plants

Directory of Open Access Journals (Sweden)

Najoua Msilini

2014-03-01

Full Text Available The effects of NO3- nutrition on iron deficiency responses were investigated in Arabidopsis thaliana. Plants were grown with or without 5 µM Fe, and with NO3- alone or a mixture of NO3- and NH4+. The results indicated that, NO3- nutrition induced higher dry matter production, regardless the Fe concentration. Fe deficiency reduced growth activity, photosynthetic pigment concentration and Fe content of plants, whatever the N forms. This decrease was more pronounced in plants grown with mixed N source; those plants presented the highest EL and MDA and anthocyanin contents compared to plants grown under Fe sufficient conditions. In iron free-solutions, with NO3- as the sole nitrogen source, enhanced FC-R activity in the roots was observed. However, in the presence of NH4+, plants displayed some decrease in in FC-R and PEPC activities. The presence of NH4+ modified typical Fe stress responses in Arabidopsis thaliana plants.

Lignin monomer composition affects Arabidopsis cell-wall degradability after liquid hot water pretreatment

Directory of Open Access Journals (Sweden)

Ladisch Michael

2010-12-01

Full Text Available Abstract Background Lignin is embedded in the plant cell wall matrix, and impedes the enzymatic saccharification of lignocellulosic feedstocks. To investigate whether enzymatic digestibility of cell wall materials can be improved by altering the relative abundance of the two major lignin monomers, guaiacyl (G and syringyl (S subunits, we compared the degradability of cell wall material from wild-type Arabidopsis thaliana with a mutant line and a genetically modified line, the lignins of which are enriched in G and S subunits, respectively. Results Arabidopsis tissue containing G- and S-rich lignins had the same saccharification performance as the wild type when subjected to enzyme hydrolysis without pretreatment. After a 24-hour incubation period, less than 30% of the total glucan was hydrolyzed. By contrast, when liquid hot water (LHW pretreatment was included before enzyme hydrolysis, the S-lignin-rich tissue gave a much higher glucose yield than either the wild-type or G-lignin-rich tissue. Applying a hot-water washing step after the pretreatment did not lead to a further increase in final glucose yield, but the initial hydrolytic rate was doubled. Conclusions Our analyses using the model plant A. thaliana revealed that lignin composition affects the enzymatic digestibility of LHW pretreated plant material. Pretreatment is more effective in enhancing the saccharification of A. thaliana cell walls that contain S-rich lignin. Increasing lignin S monomer content through genetic engineering may be a promising approach to increase the efficiency and reduce the cost of biomass to biofuel conversion.

Light-induced vegetative anthocyanin pigmentation in Petunia

Science.gov (United States)

Albert, Nick W.; Lewis, David H.; Zhang, Huaibi; Irving, Louis J.; Jameson, Paula E.; Davies, Kevin M.

2009-01-01

The Lc petunia system, which displays enhanced, light-induced vegetative pigmentation, was used to investigate how high light affects anthocyanin biosynthesis, and to assess the effects of anthocyanin pigmentation upon photosynthesis. Lc petunia plants displayed intense purple anthocyanin pigmentation throughout the leaves and stems when grown under high-light conditions, yet remain acyanic when grown under shade conditions. The coloured phenotypes matched with an accumulation of anthocyanins and flavonols, as well as the activation of the early and late flavonoid biosynthetic genes required for flavonol and anthocyanin production. Pigmentation in Lc petunia only occurred under conditions which normally induce a modest amount of anthocyanin to accumulate in wild-type Mitchell petunia [Petunia axillaris×(Petunia axillaris×Petunia hybrida cv. ‘Rose of Heaven’)]. Anthocyanin pigmentation in Lc petunia leaves appears to screen underlying photosynthetic tissues, increasing light saturation and light compensation points, without reducing the maximal photosynthetic assimilation rate (Amax). In the Lc petunia system, where the bHLH factor Leaf colour is constitutively expressed, expression of the bHLH (Lc) and WD40 (An11) components of the anthocyanin regulatory system were not limited, suggesting that the high-light-induced anthocyanin pigmentation is regulated by endogenous MYB transcription factors. PMID:19380423

Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus

OpenAIRE

Jing Zhang; Yujuan Suo; Daofeng Zhang; Fangning Jin; Hang Zhao; Chunlei Shi

2018-01-01

Staphyloxanthin (STX), a golden carotenoid pigment produced by Staphylococcus aureus, is suggested to act as an important virulence factor due to its antioxidant properties. Restraining biosynthesis of STX was considered as an indicator of virulence decline in pigmented S. aureus isolates. However, it is not clear whether natural non-pigmented S. aureus isolates have less virulence than pigmented ones. In this study, it is aimed to compare the pigmented and non-pigmented S. aureus isolates to...

Destruction of liver haem by norethindrone. Conversion into green pigments

OpenAIRE

White, Ian N. H.

1981-01-01

1. Factors affecting the norethindrone-mediated conversion of hepatic haem into green pigments have been studied in the rat. Concentrations of haem and green pigments were estimated spectrophotometrically after esterification and separation by silica gel high-pressure liquid chromatography (h.p.l.c.). 2. Accumulation of green pigments in the liver was dependent on the dose of steroid and the time after dosing, maximum values being reached after 4–8h. Phenobarbitone pretreatment of rats result...

Increased Ac excision (iae): Arabidopsis thaliana mutations affecting Ac transposition

International Nuclear Information System (INIS)

Jarvis, P.; Belzile, F.; Page, T.; Dean, C.

1997-01-01

The maize transposable element Ac is highly active in the heterologous hosts tobacco and tomato, but shows very much reduced levels of activity in Arabidopsis. A mutagenesis experiment was undertaken with the aim of identifying Arabidopsis host factors responsible for the observed low levels of Ac activity. Seed from a line carrying a single copy of the Ac element inserted into the streptomycin phosphotransferase (SPT) reporter fusion, and which displayed typically low levels of Ac activity, were mutagenized using gamma rays. Nineteen mutants displaying high levels of somatic Ac activity, as judged by their highly variegated phenotypes, were isolated after screening the M2 generation on streptomycin-containing medium. The mutations fall into two complementation groups, iae1 and iae2, are unlinked to the SPT::Ac locus and segregate in a Mendelian fashion. The iae1 mutation is recessive and the iae2 mutation is semi-dominant. The iae1 and iae2 mutants show 550- and 70-fold increases, respectively, in the average number of Ac excision sectors per cotyledon. The IAE1 locus maps to chromosome 2, whereas the SPT::Ac reporter maps to chromosome 3. A molecular study of Ac activity in the iae1 mutant confirmed the very high levels of Ac excision predicted using the phenotypic assay, but revealed only low levels of Ac re-insertion. Analyses of germinal transposition in the iae1 mutant demonstrated an average germinal excision frequency of 3% and a frequency of independent Ac re-insertions following germinal excision of 22%. The iae mutants represents a possible means of improving the efficiency of Ac/Ds transposon tagging systems in Arabidopsis, and will enable the dissection of host involvement in Ac transposition and the mechanisms employed for controlling transposable element activity

Disruptions in valine degradation affect seed development and germination in Arabidopsis.

Science.gov (United States)

Gipson, Andrew B; Morton, Kyla J; Rhee, Rachel J; Simo, Szabolcs; Clayton, Jack A; Perrett, Morgan E; Binkley, Christiana G; Jensen, Erika L; Oakes, Dana L; Rouhier, Matthew F; Rouhier, Kerry A

2017-06-01

We have functionally characterized the role of two putative mitochondrial enzymes in valine degradation using insertional mutants. Prior to this study, the relationship between branched-chain amino acid degradation (named for leucine, valine and isoleucine) and seed development was limited to leucine catabolism. Using a reverse genetics approach, we show that disruptions in the mitochondrial valine degradation pathway affect seed development and germination in Arabidopsis thaliana. A null mutant of 3-hydroxyisobutyryl-CoA hydrolase (CHY4, At4g31810) resulted in an embryo lethal phenotype, while a null mutant of methylmalonate semialdehyde dehydrogenase (MMSD, At2g14170) resulted in seeds with wrinkled coats, decreased storage reserves, elevated valine and leucine, and reduced germination rates. These data highlight the unique contributions CHY4 and MMSD make to the overall growth and viability of plants. It also increases our knowledge of the role branched-chain amino acid catabolism plays in seed development and amino acid homeostasis. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus.

Science.gov (United States)

Zhang, Jing; Suo, Yujuan; Zhang, Daofeng; Jin, Fangning; Zhao, Hang; Shi, Chunlei

2018-01-01

Staphyloxanthin (STX), a golden carotenoid pigment produced by Staphylococcus aureus , is suggested to act as an important virulence factor due to its antioxidant properties. Restraining biosynthesis of STX was considered as an indicator of virulence decline in pigmented S. aureus isolates. However, it is not clear whether natural non-pigmented S. aureus isolates have less virulence than pigmented ones. In this study, it is aimed to compare the pigmented and non-pigmented S. aureus isolates to clarify the genetic and virulent differences between the two groups. Here, 132 S. aureus isolates were divided into two phenotype groups depending on the absorbance (OD 450 ) of the extracted carotenoids. Then, all isolates were subjected to spa typing and multilocus sequence typing (MLST), and then the detection of presence of 30 virulence factors and the gene integrity of crtN and crtM . Furthermore, 24 typical S. aureus isolates and 4 S. argenteus strains were selected for the murine infection assay of in vivo virulence, in which the histological observation and enumeration of CFUs were carried out. These isolates were distributed in 26 sequence types (STs) and 49 spa types. The pigmented isolates were scattered in 25 STs, while the non-pigmented isolates were more centralized, which mainly belonged to ST20 (59%) and ST25 (13%). Among the 54 non-pigmented isolates, about 20% carried intact crtN and crtM genes. The in vivo assay suggested that comparing with pigmented S. aureus , non-pigmented S. aureus and S. argenteus strains did not show a reduced virulence in murine sepsis models. Therefore, it suggested that there were no significant genetic and virulent differences between pigmented and non-pigmented S. aureus .

Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Jing Zhang

2018-04-01

Full Text Available Staphyloxanthin (STX, a golden carotenoid pigment produced by Staphylococcus aureus, is suggested to act as an important virulence factor due to its antioxidant properties. Restraining biosynthesis of STX was considered as an indicator of virulence decline in pigmented S. aureus isolates. However, it is not clear whether natural non-pigmented S. aureus isolates have less virulence than pigmented ones. In this study, it is aimed to compare the pigmented and non-pigmented S. aureus isolates to clarify the genetic and virulent differences between the two groups. Here, 132 S. aureus isolates were divided into two phenotype groups depending on the absorbance (OD450 of the extracted carotenoids. Then, all isolates were subjected to spa typing and multilocus sequence typing (MLST, and then the detection of presence of 30 virulence factors and the gene integrity of crtN and crtM. Furthermore, 24 typical S. aureus isolates and 4 S. argenteus strains were selected for the murine infection assay of in vivo virulence, in which the histological observation and enumeration of CFUs were carried out. These isolates were distributed in 26 sequence types (STs and 49 spa types. The pigmented isolates were scattered in 25 STs, while the non-pigmented isolates were more centralized, which mainly belonged to ST20 (59% and ST25 (13%. Among the 54 non-pigmented isolates, about 20% carried intact crtN and crtM genes. The in vivo assay suggested that comparing with pigmented S. aureus, non-pigmented S. aureus and S. argenteus strains did not show a reduced virulence in murine sepsis models. Therefore, it suggested that there were no significant genetic and virulent differences between pigmented and non-pigmented S. aureus.

Annular and central heavy pigment deposition on the posterior lens capsule in the pigment dispersion syndrome: pigment deposition on the posterior lens capsule in the pigment dispersion syndrome.

Science.gov (United States)

Turgut, Burak; Türkçüoğlu, Peykan; Deniz, Nurettin; Catak, Onur

2008-12-01

To report annular and central heavy pigment deposition on the posterior lens capsule in a case of pigment dispersion syndrome. Case report. A 36-year-old female with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the right eye over the past 1-2 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including bilateral Krunkenberg spindles, iris transillumination defects, and dense trabecular meshwork pigmentation. Remarkably, annular and central dense pigmentation of the posterior lens capsule was noted in the right eye. Annular pigment deposition on the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The way of central pigmentation is the entrance of aqueous to Berger's space. In our case, it is probable that spontaneous detachment of the anterior hyaloid membrane aided this entrance.

Pigment dispersion syndrome: a clinical study.

Science.gov (United States)

Scheie, H G; Cameron, J D

1981-01-01

This study involved a group of 407 patients (799 eyes) with pigment dispersion syndrome gathered from a glaucoma population of 9200 patients. The sex distribution was equal. The majority (65%) of patients were myopic. The incidence of retinal detachment was 6.4%. No patients were black, but 5 were mulatto. Approximately one-quarter of the patients wih pigment dispersion syndrome (31% of the men, 19% of the women) had glaucoma. The average age of onset of glaucoma was 15 years less than in control patients with chronic simple glaucoma. When both eyes were affected by glaucoma, the glaucoma was consistently more severe in the eye with the more heavily pigmented angle. The degree of iris transillumination was found to be of no importance in predicting the presence of glaucoma or the severity of trabecular pigmentation. The pressure in 66% of the eyes with pigmentary glaucoma was controlled medically. A higher percentage of patients with pigmentary glaucoma required surgery than patients in the control group with chronic simple glaucoma. Men with pigmentary glaucoma required surgery at a much earlier age than women with pigmentary glaucoma. PMID:7236571

Genetic analysis of seed development in Arabidopsis thaliana = [Genetische analyse van de zaadontwikkeling in Arabidopsis thaliana

NARCIS (Netherlands)

Leon - Kloosterziel, K.

1997-01-01

This thesis deals with the genetic aspects of seed development in Arabidopsisthaliana. Mutants affected in several aspects of seed development and, more specifically, in seed maturation have been isolated by various selection

Violaxanthin de-epoxidase is rate-limiting for non-photochemical quenching under subsaturating light or during chilling in Arabidopsis.

Science.gov (United States)

Chen, Zhong; Gallie, Daniel R

2012-09-01

In response to conditions of excess light energy, plants induce non-photochemical quenching (NPQ) as a protective mechanism to prevent over reduction of photosystem II and the generation of reactive oxygen species (ROS). The xanthophyll cycle, which contributes significantly to reversible NPQ to thermally dissipate excess absorbed light energy, involves de-epoxidation of violaxanthin and antheraxanthin to zeaxanthin in response to excess light energy. The activation of violaxanthin de-epoxidase (VDE), which catalyzes the de-epoxidation reaction, requires the generation of a light-induced, transthylakoid pH gradient. In this work, we overexpressed or repressed the expression of VDE in Arabidopsis (Arabidopsis thaliana) to examine whether VDE is rate-limiting for the induction of NPQ. Increasing VDE expression increased the de-epoxidation state of xanthophyll pigments, the rate of NPQ induction, and the level of NPQ achieved under subsaturating light. In saturating light, however, overexpression of VDE did not increase the xanthophyll pigment de-epoxidation state, the level of NPQ achieved following its initial induction, or substantially improve tolerance to high light. Only under chilling, which reduces VDE activity, did an increase in VDE expression provide slightly greater phototolerance. Repression of VDE expression impaired violaxanthin de-epoxidation, reduced the generation of NPQ, and lowered the level of NPQ achieved while increasing photosensitivity. These results demonstrate that the endogenous level of VDE is rate-limiting for NPQ in Arabidopsis under subsaturating but not saturating light and can become rate-limiting under chilling conditions. These results also show that increasing VDE expression confers greater phototolerance mainly under conditions which limit endogenous VDE activity. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Arabidopsis CDS blastp result: AK288349 [KOME

Lifescience Database Archive (English)

Full Text Available AK288349 J090023P19 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 1e-23 ...

Arabidopsis CDS blastp result: AK241364 [KOME

Lifescience Database Archive (English)

Full Text Available AK241364 J065152E11 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 2e-20 ...

A dominant negative mutant of an Arabidopsis R2R3 Myb (AtMyb90) blocks flower pigment production in tobacco

Science.gov (United States)

A spontaneous mutation converted a hyper-pigmented (anthocyanins), CaMV-35S-pro::AtMYB90 containing, transgenic tobacco line into one displaying wild-type pigmentation in all tissues except for flower petals, which, counter-intuitively, showed anthocyanin levels dramatically below wild-type in the p...

Enhancing Dark Shade Pigment Dyeing of Cotton Fabric Using Plasma Treatment

Directory of Open Access Journals (Sweden)

Chi-Wai Kan

2017-07-01

Full Text Available This study is intended to investigate the effect of atmospheric pressure plasma treatment on dark shade pigment dyeing of cotton fabric. Experimental results reveal that plasma-treated cotton fabric can attain better color yield, levelness, and crocking fastness in dark shade pigment dyeing, compared with normal cotton fabric (not plasma treated. SEM analysis indicates that cracks and grooves were formed on the cotton fiber surface where the pigment and the binder can get deposited and improve the color yield, levelness, and crocking fastness. It was also noticed that pigment was aggregated when deposited on the fiber surface which could affect the final color properties.

Interaction between sugar and abscisic acid signalling during early seedling development in Arabidopsis

NARCIS (Netherlands)

Dekkers, B.J.W.; Schuurmans, J.A.M.J.; Smeekens, J.C.M.

2008-01-01

Sugars regulate important processes and affect the expression of many genes in plants. Characterization of Arabidopsis (Arabidopsis thaliana) mutants with altered sugar sensitivity revealed the function of abscisic acid (ABA) signalling in sugar responses. However, the exact interaction between

Iris phenotypes and pigment dispersion caused by genes influencing pigmentation.

Science.gov (United States)

Anderson, Michael G; Hawes, Norman L; Trantow, Colleen M; Chang, Bo; John, Simon W M

2008-10-01

Spontaneous mutations altering mouse coat colors have been a classic resource for discovery of numerous molecular pathways. Although often overlooked, the mouse iris is also densely pigmented and easily observed, thus representing a similarly powerful opportunity for studying pigment cell biology. Here, we present an analysis of iris phenotypes among 16 mouse strains with mutations influencing melanosomes. Many of these strains exhibit biologically and medically relevant phenotypes, including pigment dispersion, a common feature of several human ocular diseases. Pigment dispersion was identified in several strains with mutant alleles known to influence melanosomes, including beige, light, and vitiligo. Pigment dispersion was also detected in the recently arising spontaneous coat color variant, nm2798. We have identified the nm2798 mutation as a missense mutation in the Dct gene, an identical re-occurrence of the slaty light mutation. These results suggest that dysregulated events of melanosomes can be potent contributors to the pigment dispersion phenotype. Combined, these findings illustrate the utility of studying iris phenotypes as a means of discovering new pathways, and re-linking old ones, to processes of pigmented cells in health and disease.

Loci associated with skin pigmentation identified in African populations

Science.gov (United States)

Crawford, Nicholas G.; Kelly, Derek E.; Hansen, Matthew E. B.; Beltrame, Marcia H.; Fan, Shaohua; Bowman, Shanna L.; Jewett, Ethan; Ranciaro, Alessia; Thompson, Simon; Lo, Yancy; Pfeifer, Susanne P.; Jensen, Jeffrey D.; Campbell, Michael C.; Beggs, William; Hormozdiari, Farhad; Mpoloka, Sununguko Wata; Mokone, Gaonyadiwe George; Nyambo, Thomas; Meskel, Dawit Wolde; Belay, Gurja; Haut, Jake; Rothschild, Harriet; Zon, Leonard; Zhou, Yi; Kovacs, Michael A.; Xu, Mai; Zhang, Tongwu; Bishop, Kevin; Sinclair, Jason; Rivas, Cecilia; Elliot, Eugene; Choi, Jiyeon; Li, Shengchao A.; Hicks, Belynda; Burgess, Shawn; Abnet, Christian; Watkins-Chow, Dawn E.; Oceana, Elena; Song, Yun S.; Eskin, Eleazar; Brown, Kevin M.; Marks, Michael S.; Loftus, Stacie K.; Pavan, William J.; Yeager, Meredith; Chanock, Stephen; Tishkoff, Sarah

2017-01-01

Despite the wide range of skin pigmentation in humans, little is known about its genetic basis in global populations. Examining ethnically diverse African genomes, we identify variants in or near SLC24A5, MFSD12, DDB1, TMEM138, OCA2 and HERC2 that are significantly associated with skin pigmentation. Genetic evidence indicates that the light pigmentation variant at SLC24A5 was introduced into East Africa by gene flow from non-Africans. At all other loci, variants associated with dark pigmentation in Africans are identical by descent in southern Asian and Australo-Melanesian populations. Functional analyses indicate that MFSD12 encodes a lysosomal protein that affects melanogenesis in zebrafish and mice, and that mutations in melanocyte-specific regulatory regions near DDB1/TMEM138 correlate with expression of UV response genes under selection in Eurasians. PMID:29025994

Dense pigmentation of the posterior lens capsule associated with the pigment dispersion syndrome.

Science.gov (United States)

Lin, Danny Y; Volpicelli, Mark; Singh, Kuldev

2003-12-01

To report an unusual case of pigment dispersion syndrome associated with unilateral dense pigmentation of the posterior lens capsule. Case report. A 59-year-old male with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the left eye over the past 10 to 20 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including the presence of bilateral Krunkenberg spindles, iris transillumination defects, and heavy trabecular meshwork pigmentation. Of note, there was remarkably dense pigmentation of the posterior lens capsule in the eye with decreased visual acuity. Pigmentation of the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The optimal treatment of this unusual condition remains undetermined.

Arabidopsis FH1 Formin Affects Cotyledon Pavement Cell Shape by Modulating Cytoskeleton Dynamics

Czech Academy of Sciences Publication Activity Database

Rosero, A.; Oulehlová, Denisa; Stillerová, L.; Schiebertová, P.; Gunt, M.; Žárský, Viktor; Cvrčková, F.

2016-01-01

Roč. 57, č. 3 (2016), s. 488-504 ISSN 0032-0781 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * Confocal microscopy * Cotyledon pavement cells Subject RIV: ED - Physiology Impact factor: 4.760, year: 2016

Arabidopsis VARIEGATED 3 encodes a chloroplasttargeted, zinc-finger protein required for chloroplast and palisade cell development

DEFF Research Database (Denmark)

Næsted, Henrik; Holm, A.; Jenkins, T.

2004-01-01

The stable, recessive Arabidopsis variegated 3 (var3) mutant exhibits a variegated phenotype due to somatic areas lacking or containing developmentally retarded chloroplasts and greatly reduced numbers of palisade cells. The VAR3 gene, isolated by transposon tagging, encodes the 85.9 kDa VAR3...... that pigment profiles are qualitatively similar in wild type and var3, although var3 accumulates lower levels of chlorophylls and carotenoids. These results indicate that VAR3 is a part of a protein complex required for normal chloroplast and palisade cell development....

Abscisic acid deficiency increases defence responses against Myzus persicae in Arabidopsis.

Science.gov (United States)

Hillwig, Melissa S; Chiozza, Mariana; Casteel, Clare L; Lau, Siau Ting; Hohenstein, Jessica; Hernández, Enrique; Jander, Georg; MacIntosh, Gustavo C

2016-02-01

Comparison of Arabidopsis thaliana (Arabidopsis) gene expression induced by Myzus persicae (green peach aphid) feeding, aphid saliva infiltration and abscisic acid (ABA) treatment showed a significant positive correlation. In particular, ABA-regulated genes are over-represented among genes that are induced by M. persicae saliva infiltration into Arabidopsis leaves. This suggests that the induction of ABA-related gene expression could be an important component of the Arabidopsis-aphid interaction. Consistent with this hypothesis, M. persicae populations induced ABA production in wild-type plants. Furthermore, aphid populations were smaller on Arabidopsis aba1-1 mutants, which cannot synthesize ABA, and showed a significant preference for wild-type plants compared with the mutant. Total free amino acids, which play an important role in aphid nutrition, were not altered in the aba1-1 mutant line, but the levels of isoleucine (Ile) and tryptophan (Trp) were differentially affected by aphids in wild-type and mutant plants. Recently, indole glucosinolates have been shown to promote aphid resistance in Arabidopsis. In this study, 4-methoxyindol-3-ylmethylglucosinolate was more abundant in the aba1-1 mutant than in wild-type Arabidopsis, suggesting that the induction of ABA signals that decrease the accumulation of defence compounds may be beneficial for aphids. © 2015 BSPP AND JOHN WILEY & SONS LTD.

Zinc deficiency leads to lipofuscin accumulation in the retinal pigment epithelium of pigmented rats.

Directory of Open Access Journals (Sweden)

Sylvie Julien

Full Text Available BACKGROUND: Age-related macular degeneration (AMD is associated with lipofuscin accumulation whereas the content of melanosomes decreases. Melanosomes are the main storage of zinc in the pigmented tissues. Since the elderly population, as the most affected group for AMD, is prone to zinc deficit, we investigated the chemical and ultrastructural effects of zinc deficiency in pigmented rat eyes after a six-month zinc penury diet. METHODOLOGY/PRINCIPAL FINDINGS: Adult Long Evans (LE rats were investigated. The control animals were fed with a normal alimentation whereas the zinc-deficiency rats (ZD-LE were fed with a zinc deficient diet for six months. Quantitative Energy Dispersive X-ray (EDX microanalysis yielded the zinc mole fractions of melanosomes in the retinal pigment epithelium (RPE. The lateral resolution of the analysis was 100 nm. The zinc mole fractions of melanosomes were significantly smaller in the RPE of ZD-LE rats as compared to the LE control rats. Light, fluorescence and electron microscopy, as well as immunohistochemistry were performed. The numbers of lipofuscin granules in the RPE and of infiltrated cells (Ø>3 µm found in the choroid were quantified. The number of lipofuscin granules significantly increased in ZD-LE as compared to control rats. Infiltrated cells bigger than 3 µm were only detected in the choroid of ZD-LE animals. Moreover, the thickness of the Bruch's membrane of ZD-LE rats varied between 0.4-3 µm and thin, rangy ED1 positive macrophages were found attached at these sites of Bruch's membrane or even inside it. CONCLUSIONS/SIGNIFICANCE: In pigmented rats, zinc deficiency yielded an accumulation of lipofuscin in the RPE and of large pigmented macrophages in the choroids as well as the appearance of thin, rangy macrophages at Bruch's membrane. Moreover, we showed that a zinc diet reduced the zinc mole fraction of melanosomes in the RPE and modulated the thickness of the Bruch's membrane.

Isolation of mutations affecting the development of freezing tolerance in Arabidopsis thaliana (L.) Heynh.

Science.gov (United States)

Warren, G; McKown, R; Marin, A L; Teutonico, R

1996-08-01

We screened for mutations deleterious to the freezing tolerance of Arabidopsis thaliana (L.) Heynh. ecotype Columbia. Tolerance was assayed by the vigor and regrowth of intact plants after cold acclimation and freezing. From a chemically mutagenized population, we obtained 13 lines of mutants with highly penetrant phenotypes. In 5 of these, freezing sensitivity was attributable to chilling injury sustained during cold acclimation, but in the remaining 8 lines, the absence of injury prior to freezing suggested that they were affected specifically in the development of freezing tolerance. In backcrosses, freezing sensitivity from each line segregated as a single nuclear mutation. Complementation tests indicated that the 8 lines contained mutations in 7 different genes. The mutants' freezing sensitivity was also detectable in the leakage of electrolytes from frozen leaves. However, 1 mutant line that displayed a strong phenotype at the whole-plant level showed a relatively weak phenotype by the electrolyte leakage assay.

Ecological-friendly pigments from fungi.

Science.gov (United States)

Durán, Nelson; Teixeira, Maria F S; De Conti, Roseli; Esposito, Elisa

2002-01-01

The dyestuff industry is suffering from the increases in costs of feedstock and energy for dye synthesis, and they are under increasing pressure to minimize the damage to the environment. The industries are continuously looking for cheaper, more environmentally friendly routes to existing dyes. The aim of this minireview is to discuss the most important advances in the fungal pigment area and its interest in biotechnological applications. Characteristic pigments are produced by a wide variety of fungi and the chemical composition of natural dyes are described. These pigments exhibit several biological activities besides cytotoxicity. The synthetic pigments authorized by the EC and in USA and the natural pigments available in the world market are discussed. The obstacle to the exploitation of new natural pigments sources is the food legislation, requesting costly toxicological research, manufacturing costs, and acceptance by consumers. The dislike for novel ingredients is likely to be the biggest impediment for expansion of the pigment list in the near future. If the necessary toxicological testing and the comparison with accepted pigments are made, the fungal pigments, could be acceptable by the current consumer. The potentiality of pigment production in Brazil is possible due to tremendous Amazonian region biodiversity.

Manipulation of hemoglobin expression affects Arabidopsis shoot organogenesis

DEFF Research Database (Denmark)

Wang, Yaping; Elhiti, Mohamed; Hebelstrup, Kim

2011-01-01

Over the past few years non-symbiotic plant hemoglobins have been described in a variety of plant species where they fulfill several functions ranging from detoxification processes to basic aspects of plant growth and post-embryonic development. To date no information is available on the role...... of hemoglobins during invitro morphogenesis. Shoot organogenesis was induced in Arabidopsis lines constitutively expressing class 1, 2 and 3 hemoglobins (GLB1, 2 and 3) and lines in which the respective genes were either downregulated by RNAi (GLB1) or knocked out (GLB2 and GLB3). The process was executed......, 15, and 16), feed-back repressors of the cytokinin pathway, was repressed in both hemoglobin over-expressors whereas that of several Type-B ARRs (ARR2, 12, and 13), transcription activators of cytokinin-responsive genes, was induced. Such changes enhanced the sensitivity of the root explants...

Melanin targeting for intracellular drug delivery: Quantification of bound and free drug in retinal pigment epithelial cells.

Science.gov (United States)

Rimpelä, Anna-Kaisa; Hagström, Marja; Kidron, Heidi; Urtti, Arto

2018-05-31

Melanin binding affects drug distribution and retention in pigmented ocular tissues, thereby affecting drug response, duration of activity and toxicity. Therefore, it is a promising possibility for drug targeting and controlled release in the pigmented cells and tissues. Intracellular unbound drug concentrations determine pharmacological and toxicological actions, but analyses of unbound vs. total drug concentrations in pigmented cells are lacking. We studied intracellular binding and cellular drug uptake in pigmented retinal pigment epithelial cells and in non-pigmented ARPE-19 cells with five model drugs (chloroquine, propranolol, timolol, diclofenac, methotrexate). The unbound drug fractions in pigmented cells were 0.00016-0.73 and in non-pigmented cells 0.017-1.0. Cellular uptake (i.e. distribution ratio Kp), ranged from 1.3 to 6300 in pigmented cells and from 1.0 to 25 in non-pigmented cells. Values for intracellular bioavailability, F ic , were similar in both cells types (although larger variation in pigmented cells). In vitro melanin binding parameters were used to predict intracellular unbound drug fraction and cell uptake. Comparison of predictions with experimental data indicates that other factors (e.g. ion-trapping, lipophilicity-related binding to other cell components) also play a role. Melanin binding is a major factor that leads to cellular uptake and unbound drug fractions of a range of 3-4 orders of magnitude indicating that large reservoirs of melanin bound drug can be generated in the cells. Understanding melanin binding has important implications on retinal drug targeting, efficacy and toxicity. Copyright © 2017. Published by Elsevier B.V.

Treatment of gingival pigmentation : A case series

Directory of Open Access Journals (Sweden)

Prasad Deepak

2005-01-01

Full Text Available A smile expresses a feeling of joy, success, sensuality, affection and courtesy, and reveals self confidence and kindness. The harmony of the smile is determined not only by the shape, the position and the color of the teeth but also by the gingival tissues. Gingival health and appearance are essential components of an attractive smile. Gingival pigmentation results from melanin granules, which are produced by melanoblasts. The degree of pigmentation depends on melanoblastic activity. Although melanin pigmentation of the gingiva is completely benign and does not present a medical problem, complaints of ′black gums′ are common particularly in patients having a very high smile line (gummy smile. For depigmentation of gingiva different treatment modalities have been reported like- Bur abrasion, scraping, partial thickness flap, cryotherapy, electrosurgery and laser. In the present case series bur abrasion, scraping, partial thickness flap (epithelial excision cryotherapy and electrosurgery have been tried for depigmentation, which are simple, effective and yield good results, along with good patient satisfaction. The problems encountered with some of these techniques have also been discussed.

SKL1 Is Essential for Chloroplast Development in Arabidopsis

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Huimin Xu

2018-02-01

Full Text Available The Arabidopsis shikimate kinase-like 1 (skl1-8 mutant is characterized by a pigment-defective phenotype. Although the related phenotypical defect mainly has been attributed to the blocking of chloroplast development, the molecular functions of SKL1 remain largely unknown. In this study, we combined multiple approaches to investigate the potential functions of SKL1. Results showed that the skl1-8 mutant exhibited an albino phenotype and had dramatically reduced chlorophyll content as a consequence of a single nuclear recessive gene mutation. Chemical complementation analysis indicated that SKL1 does not function as SK enzyme in the shikimate pathway. In addition, by chlorophyll fluorescence parameters and immunoblot analysis, the levels of photosynthetic proteins are substantially reduced. Moreover, by transcriptome analysis, specific groups of nuclear genes involved in photosynthesis, such as light-harvesting complex, pigment metabolism, carbon metabolism, and chloroplast gene expression, were down-regulated, whereas several defense and oxidative stress responsive genes were up-regulated in the skl1-8 mutant compared with the wide type. Furthermore, we found the expression of genes related to auxin transport and response was repressed in the skl1-8 mutant, probable suggesting that SKL1 is involved in auxin-related pathways during chloroplast development. Together, these results provide a useful reference for characterization of SKL1 function during chloroplast biogenesis and development.

Retinal pigment epithelial dystrophy in Briard dogs.

Science.gov (United States)

Lightfoot, R M; Cabral, L; Gooch, L; Bedford, P G; Boulton, M E

1996-01-01

The eyes of normal Briard dogs, Briards affected with inherited retinal pigment epithelial dystrophy (RPED) and a range of normal crossbred and beagle dogs were examined and the histopathology of RPED in the Briard was compared with the histopathological features of ageing in the normal canine retina. RPED was characterised by the accumulation of auto-fluorescent lipofuscin-like inclusions in the retinal pigment epithelium (RPE), which initially involved only non-pigmented RPE cells overlying the tapetum but subsequently spread to all pigmented RPE cells. Secondary neuro-retinal degeneration was characterised by a gradual loss of the outer nuclear layer and the subsequent atrophy and degeneration of the inner retina. The loss of primary photoreceptors in the peripheral retina was accompanied by the migration of photoreceptor nuclei and appeared to resemble severe changes due to ageing. Intra-vitreal radiolabelled leucine was used to examine the rate of turnover of the outer segments of the rods in some Briards, but no significant variations were found. The activity of acid phosphatase in RPE was assayed in vitro and showed comparable regional variations in Briard and crossbred dogs. The results suggest that RPED in the Briard is unlikely to be due either to an increased rate of turnover of rod outer segments (and thus an increased phagocytic load) or to a primary insufficiency of lysosomal enzyme.

Production of a Blue Pigment (Glaukothalin by Marine Rheinheimera spp.

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Hans-Peter Grossart

2009-01-01

Full Text Available Two γ-Proteobacteria strains, that is, HP1 and HP9, which both produce a diffusible deep blue pigment, were isolated from the German Wadden Sea and from the Øresund, Denmark, respectively. Both strains affiliate with the genus Rheinheimera. Small amounts of the pigment could be extracted from HP1 grown in a 50 L fermenter and were purified chromatographically. Chemical analysis of the pigment including NMR and mass spectrometry led to a molecular formula of C34H56N4O4 (m.w. 584.85 which has not yet been reported in literature. The molecule is highly symmetrically and consists of two heterocyclic halves to which aliphatic side chains are attached. The pigment has been named glaukothalin due to its blue color and its marine origin (glaukos, gr.=blue, thalatta, gr.=sea. Production of glaukothalin on MB2216 agar plates by our Rheinheimera strains is affected in the presence of other bacterial strains either increasing or decreasing pigment production. The addition of a single amino acid, arginine (5 gl−1, greatly increases pigment production by our Rheinheimera strains. Even though the production of glaukothalin leads to inhibitory activity against three bacterial strains from marine particles, our Rheinheimera isolates are inhibited by various bacteria of different phylogenetic groups. The ecological role of glaukothalin production by Rheinheimera strains, however, remains largely unknown.

Carbachol-mediated pigment granule dispersion in retinal pigment epithelium requires Ca2+ and calcineurin

OpenAIRE

Johnson, Adam S; Garc?a, Dana M

2007-01-01

Abstract Background Inside bluegill (Lepomis macrochirus) retinal pigment epithelial cells, pigment granules move in response to extracellular signals. During the process of aggregation, pigment motility is directed toward the cell nucleus; in dispersion, pigment is directed away from the nucleus and into long apical processes. A number of different chemicals have been found to initiate dispersion, and carbachol (an acetylcholine analog) is one example. Previous research indicates that the ca...

Arabidopsis VARIEGATED 3 encodes a chloroplast-targeted, zinc-finger protein required for chloroplast and palisade cell development

DEFF Research Database (Denmark)

Næsted, Henrik; Holm, Agnethe; Jenkins, Tom

2004-01-01

The stable, recessive Arabidopsis variegated 3 (var3) mutant exhibits a variegated phenotype due to somatic areas lacking or containing developmentally retarded chloroplasts and greatly reduced numbers of palisade cells. The VAR3 gene, isolated by transposon tagging, encodes the 85.9 kDa VAR3...... that pigment profiles are qualitatively similar in wild type and var3, although var3 accumulates lower levels of chlorophylls and carotenoids. These results indicate that VAR3 is a part of a protein complex required for normal chloroplast and palisade cell development....

Ambient temperature and genotype differentially affect developmental and phenotypic plasticity in Arabidopsis thaliana.

Science.gov (United States)

Ibañez, Carla; Poeschl, Yvonne; Peterson, Tom; Bellstädt, Julia; Denk, Kathrin; Gogol-Döring, Andreas; Quint, Marcel; Delker, Carolin

2017-07-06

Global increase in ambient temperatures constitute a significant challenge to wild and cultivated plant species. Forward genetic analyses of individual temperature-responsive traits have resulted in the identification of several signaling and response components. However, a comprehensive knowledge about temperature sensitivity of different developmental stages and the contribution of natural variation is still scarce and fragmented at best. Here, we systematically analyze thermomorphogenesis throughout a complete life cycle in ten natural Arabidopsis thaliana accessions grown under long day conditions in four different temperatures ranging from 16 to 28 °C. We used Q 10 , GxE, phenotypic divergence and correlation analyses to assess temperature sensitivity and genotype effects of more than 30 morphometric and developmental traits representing five phenotype classes. We found that genotype and temperature differentially affected plant growth and development with variing strengths. Furthermore, overall correlations among phenotypic temperature responses was relatively low which seems to be caused by differential capacities for temperature adaptations of individual accessions. Genotype-specific temperature responses may be attractive targets for future forward genetic approaches and accession-specific thermomorphogenesis maps may aid the assessment of functional relevance of known and novel regulatory components.

Hemoglobin is essential for normal growth of Arabidopsis organs

DEFF Research Database (Denmark)

Hebelstrup, Kim Henrik; Hunt, Peter; Dennis, Elizabeth

2006-01-01

In Arabidopsis thaliana, the class I hemoglobin AHb1 is transiently expressed in the hydathodes of leaves and in floral buds from young inflorescences. Nitric oxide (NO) accumulates to high levels in these organs when AHb1 is silenced, indicating an important role in metabolizing NO. AHb1-silenced...... lines are viable but show a mutant phenotype affecting the regions where AHb1 is expressed. Arabidopsis lines with an insertional knockout or overexpression of AHb2, a class II 3-on-3 hemoglobin, were generated. Seedlings overexpressing AHb2 show enhanced survival of hypoxic stress. The AHb2 knockout...... lines develop normally. However, when AHb2 knockout is combined with AHb1 silencing, seedlings die at an early vegetative stage suggesting that the two 3-on-3 hemoglobins, AHb1 and AHb2, together play an essential role for normal development of Arabidopsis seedlings. In conclusion, these results...

Light and the E3 ubiquitin ligase COP1/SPA control the protein stability of the MYB transcription factors PAP1 and PAP2 involved in anthocyanin accumulation in Arabidopsis.

Science.gov (United States)

Maier, Alexander; Schrader, Andrea; Kokkelink, Leonie; Falke, Christian; Welter, Bastian; Iniesto, Elisa; Rubio, Vicente; Uhrig, Joachim F; Hülskamp, Martin; Hoecker, Ute

2013-05-01

Anthocyanins are natural pigments that accumulate only in light-grown and not in dark-grown Arabidopsis plants. Repression of anthocyanin accumulation in darkness requires the CONSTITUTIVELY PHOTOMORPHOGENIC1/SUPPRESSOR OF PHYA-105 (COP1/SPA) ubiquitin ligase, as cop1 and spa mutants produce anthocyanins also in the dark. Here, we show that COP1 and SPA proteins interact with the myeloblastosis (MYB) transcription factors PRODUCTION OF ANTHOCYANIN PIGMENT1 (PAP)1 and PAP2, two members of a small protein family that is required for anthocyanin accumulation and for the expression of structural genes in the anthocyanin biosynthesis pathway. The increased anthocyanin levels in cop1 mutants requires the PAP1 gene family, indicating that COP1 functions upstream of the PAP1 gene family. PAP1 and PAP2 proteins are degraded in the dark and this degradation is dependent on the proteasome and on COP1. Hence, the light requirement for anthocyanin biosynthesis results, at least in part, from the light-mediated stabilization of PAP1 and PAP2. Consistent with this conclusion, moderate overexpression of PAP1 leads to an increase in anthocyanin levels only in the light and not in darkness. Here we show that SPA genes are also required for reducing PAP1 and PAP2 transcript levels in dark-grown seedlings. Taken together, these results indicate that the COP1/SPA complex affects PAP1 and PAP2 both transcriptionally and post-translationally. Thus, our findings have identified mechanisms via which the COP1/SPA complex controls anthocyanin levels in Arabidopsis that may be useful for applications in biotechnology directed towards increasing anthocyanin content in plants. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Long anterior zonules and pigment dispersion.

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Moroi, Sayoko E; Lark, Kurt K; Sieving, Paul A; Nouri-Mahdavi, Kouros; Schlötzer-Schrehardt, Ursula; Katz, Gregory J; Ritch, Robert

2003-12-01

To describe pigment dispersion associated with long anterior zonules. Multicenter observational case series. Fifteen patients, seven of whom were treated for glaucoma or ocular hypertension, were identified with long anterior zonules and pigment dispersion. Transmission electron microscopy was performed on one anterior capsule specimen. All patients had anterior zonules that inserted centrally on the lens capsule. Signs of pigment dispersion included corneal endothelial pigmentation, loss of the pupillary ruff, and variable trabecular meshwork pigmentation. Ultrasound biomicroscopy verified the lack of posterior iris insertion and concavity. There was no exfoliation material. Transmission electron microscopy showed zonular lamellae with adherent pigment granules, and no exfoliation material. Long anterior zonules inserted onto the central lens capsule may cause mechanical disruption of the pigment epithelium at the pupillary ruff and central iris leading to pigment dispersion.

Identification of Yellow Pigmentation Genes in Brassica rapa ssp. pekinensis Using Br300 Microarray

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Hee-Jeong Jung

2014-01-01

Full Text Available The yellow color of inner leaves in Chinese cabbage depends on its lutein and carotene content. To identify responsible genes for yellow pigmentation in leaves, the transcriptome profiles of white (Kenshin and yellow leaves (Wheessen were examined using the Br300K oligomeric chip in Chinese cabbage. In yellow leaves, genes involved in carotene synthesis (BrPSY, BrPDS, BrCRTISO, and BrLCYE, lutein, and zeaxanthin synthesis (BrCYP97A3 and BrHYDB were upregulated, while those associated with carotene degradation (BrNCED3, BrNCED4, and BrNCED6 were downregulated. These expression patterns might support that the content of both lutein and total carotenoid was much higher in the yellow leaves than that in the white leaves. These results indicate that the yellow leaves accumulate high levels of both lutein and β-carotene due to stimulation of synthesis and that the degradation rate is inhibited. A large number of responsible genes as novel genes were specifically expressed in yellow inner leaves, suggesting the possible involvement in pigment synthesis. Finally, we identified three transcription factors (BrA20/AN1-like, BrBIM1, and BrZFP8 that are specifically expressed and confirmed their relatedness in carotenoid synthesis from Arabidopsis plants.

Photosynthetic Pigments in Diatoms.

Science.gov (United States)

Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

2015-09-16

Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.

Photosynthetic Pigments in Diatoms

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Paulina Kuczynska

2015-09-01

Full Text Available Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.

Ascophyllum nodosum Seaweed Extract Alleviates Drought Stress in Arabidopsis by Affecting Photosynthetic Performance and Related Gene Expression

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Antonietta Santaniello

2017-08-01

Full Text Available Drought represents one of the most relevant abiotic stress affecting growth and yield of crop plants. In order to improve the agricultural productivity within the limited water and land resources, it is mandatory to increase crop yields in presence of unfavorable environmental stresses. The use of biostimulants, often containing seaweed extracts, represents one of the options for farmers willing to alleviate abiotic stress consequences on crops. In this work, we investigated the responses of Arabidopsis plants treated with an extract from the brown alga Ascophyllum nodosum (ANE, under drought stress conditions, demonstrating that ANE positively influences Arabidopsis survival. Pre-treatment with ANE induced a partial stomatal closure, associated with changes in the expression levels of genes involved in ABA-responsive and antioxidant system pathways. The pre-activation of these pathways results in a stronger ability of ANE-treated plants to maintain a better photosynthetic performance compared to untreated plants throughout the dehydration period, combined with a higher capacity to dissipate the excess of energy as heat in the reaction centers of photosystem II. Our results suggest that drought stressed plants treated with ANE are able to maintain a strong stomatal control and relatively higher values of both water use efficiency (WUE and mesophyll conductance during the last phase of dehydration. Simultaneously, the activation of a pre-induced antioxidant defense system, in combination with a more efficient energy dissipation mechanism, prevents irreversible damages to the photosynthetic apparatus. In conclusion, pre-treatment with ANE is effective to acclimate plants to the incoming stress, promoting an increased WUE and dehydration tolerance.

Identification of genes affecting the response of tomato and Arabidopsis upon powdery mildew infection

NARCIS (Netherlands)

Gao, D.

2014-01-01

Many plant species are hosts of powdery mildew fungi, including Arabidopsis and economically important crops such as wheat, barley and tomato. Resistance has been explored using induced mutagenesis and natural variation in the plant species. The isolated genes encompass loss-of-function

Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill.

Science.gov (United States)

González, Alfredo; Crittenden, Elizabeth L; García, Dana M

2004-07-13

In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl) carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion.

Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill

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Crittenden Elizabeth L

2004-07-01

Full Text Available Abstract Background In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. Results The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Conclusions Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion.

Natural pigments and sacred art

Science.gov (United States)

Kelekian, Lena, ,, Lady

2010-05-01

Since the dawn of mankind, cavemen has expressed himself through art. The earliest known cave paintings date to some 32,000 years ago and used 4 colours derived from the earth. These pigments were iron oxides and known as ochres, blacks and whites. All pigments known by the Egyptians, the Greeks, the Romans and Renaissance man were natural and it was not until the 18th century that synthetic pigments were made and widely used. Until that time all art, be it sacred or secular used only natural pigments, of which the preparation of many have been lost or rarely used because of their tedious preparation. As a geologist, a mineralogist and an artist specializing in iconography, I have been able to rediscover 89 natural pigments extracted from minerals. I use these pigments to paint my icons in the traditional Byzantine manner and also to restore old icons, bringing back their glamour and conserving them for years to come. The use of the natural pigments in its proper way also helps to preserve the traditional skills of the iconographer. In the ancient past, pigments were extremely precious. Many took an exceedingly long journey to reach the artists, and came from remote countries. Research into these pigments is the work of history, geography and anthropology. It is an interesting journey in itself to discover that the blue aquamarines came from Afghanistan, the reds from Spain, the greens Africa, and so on. In this contribution I will be describing the origins, preparation and use of some natural pigments, together with their history and provenance. Additionally, I will show how the natural pigments are used in the creation of an icon. Being a geologist iconographer, for me, is a sacrement that transforms that which is earthly, material and natural into a thing of beauty that is sacred. As bread and wine in the Eucharist, water during baptism and oil in Holy Union transmit sanctification to the beholder, natural pigments do the same when one considers an icon. The

Phototrophic pigment production with microalgae

NARCIS (Netherlands)

Mulders, K.J.M.

2014-01-01

Abstract

Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main focus on secondary

Corrosion resistance of flaky aluminum pigment coated with cerium oxides/hydroxides in chloride and acidic electrolytes

International Nuclear Information System (INIS)

Niroumandrad, S.; Rostami, M.; Ramezanzadeh, B.

2015-01-01

Graphical abstract: - Highlights: • Flaky aluminum pigments were modified with cerium nitrate salt. • pH value of 3.0 was chosen as the optimized pH for the cerium solution. • Corrosion resistance of the pigment significantly increased after modification. • Alkaline pre-treatment prior to modification affected the cerium layer performance. - Abstract: The objective of this study was to enhance the corrosion resistance of lamellar aluminum pigment through surface treatment by cerium oxides/hydroxides. The surface composition of the pigments was studied by energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the pigment was evaluated by conventional hydrogen evolution measurements in acidic solution and electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution. Results showed that the Ce-rich coating composed of Ce 2 O 3 and CeO 2 was precipitated on the pigment surface after immersion in the cerium solution. The corrosion resistance of pigment was significantly enhanced after modification with cerium layer.

Corrosion resistance of flaky aluminum pigment coated with cerium oxides/hydroxides in chloride and acidic electrolytes

Energy Technology Data Exchange (ETDEWEB)

Niroumandrad, S. [Institute for Color Science and Technology (ICST), PO 16765-654, Tehran (Iran, Islamic Republic of); Rostami, M. [Department of Nanomaterials and Nanocoatings, Institute for Color Science and Technology (ICST), PO 16765-654, Tehran (Iran, Islamic Republic of); Ramezanzadeh, B., E-mail: ramezanzadeh-bh@icrc.ac.ir [Department of Surface Coatings and Corrosion, Institute for Color Science and Technology (ICST), PO 16765-654, Tehran (Iran, Islamic Republic of)

2015-12-01

Graphical abstract: - Highlights: • Flaky aluminum pigments were modified with cerium nitrate salt. • pH value of 3.0 was chosen as the optimized pH for the cerium solution. • Corrosion resistance of the pigment significantly increased after modification. • Alkaline pre-treatment prior to modification affected the cerium layer performance. - Abstract: The objective of this study was to enhance the corrosion resistance of lamellar aluminum pigment through surface treatment by cerium oxides/hydroxides. The surface composition of the pigments was studied by energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The corrosion resistance of the pigment was evaluated by conventional hydrogen evolution measurements in acidic solution and electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution. Results showed that the Ce-rich coating composed of Ce{sub 2}O{sub 3} and CeO{sub 2} was precipitated on the pigment surface after immersion in the cerium solution. The corrosion resistance of pigment was significantly enhanced after modification with cerium layer.

Burkholderia phytofirmans PsJN reduces damages to freezing temperature in Arabidopsis thaliana

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Fan eSU

2015-10-01

Full Text Available Several plant growth-promoting rhizobacteria (PGPR are known to improve plant tolerance to multiple stresses, including low temperatures. However, mechanisms underlying this protection are still poorly understood. The aim of this study was to evaluate the role of the endophytic PGPR, Burkholderia phytofirmans strain PsJN (Bp PsJN, on Arabidopsis thaliana cold tolerance using photosynthesis parameters as physiological markers.Under standard conditions, our results indicated that Bp PsJN inoculation led to growth promotion of Arabidopsis plants without significant modification on photosynthesis parameters and chloroplast organization. However, bacterial colonization induced a cell wall strengthening in the mesophyllImpact of inoculation modes (either on seeds or by soil irrigation and their effects overnight at 0, -1 or -3°C, were investigated by following photosystem II (PSII activity and gas exchanges. Following low temperatures stress, a decrease of photosynthesis parameters was observed. In addition, during three consecutive nights or days at -1°C, PSII activity was monitored. Pigment contents, RuBisCO protein abundance, expression of several genes including RbcS, RbcL, CBF1, CBF2, CBF3, ICE1, COR15a, and COR78 were evaluated at the end of exposure. To assess the impact of the bacteria on cell ultrastructure under low temperatures, microscopic observations were achieved. Results indicated that freezing treatment induced significant changes in PSII activity as early as the first cold day, whereas the same impact on PSII activity was observed only during the third cold night. The significant effects conferred by PsJN were differential accumulation of pigments, and reduced expression of RbcL and COR78. Microscopical observations showed an alteration/disorganization in A. thaliana leaf mesophyll cells independently of the freezing treatments. The presence of bacteria during the three successive nights or days did not significantly improved A

Diversity and functional properties of bistable pigments.

Science.gov (United States)

Tsukamoto, Hisao; Terakita, Akihisa

2010-11-01

Rhodopsin and related opsin-based pigments, which are photosensitive membrane proteins, have been extensively studied using a wide variety of techniques, with rhodopsin being the most understood G protein-coupled receptor (GPCR). Animals use various opsin-based pigments for vision and a wide variety of non-visual functions. Many functionally varied pigments are roughly divided into two kinds, based on their photoreaction: bistable and monostable pigments. Bistable pigments are thermally stable before and after photo-activation, but monostable pigments are stable only before activation. Here, we review the diversity of bistable pigments and their molecular characteristics. We also discuss the mechanisms underlying different molecular characteristics of bistable and monostable pigments. In addition, the potential of bistable pigments as a GPCR model is proposed.

New blue pigment produced by Pantoea agglomerans and its production characteristics at various temperatures.

Science.gov (United States)

Fujikawa, Hiroshi; Akimoto, Ryo

2011-01-01

A bacterium capable of producing a deep blue pigment was isolated from the environment and identified as Pantoea agglomerans. The pigment production characteristics of the bacterium under various conditions were studied. The optimal agar plate ingredients for pigment production by the bacterium were first studied: the optimal ingredients were 5 g/liter glucose, 10 g/liter tryptic soy broth, and 40 g/liter glycerol at pH 6.4. Bacterial cells grew on the agar plate during the incubation, while the pigment spread into the agar plate, meaning that it is water soluble. Pigment production was affected by the initial cell density. Namely, at higher initial cell densities ranging from 10(6.3) to 10(8.2) CFU/cm(2) on the agar plate, faster pigment production was observed, but no blue pigment was produced at a very high initial density of 10(9.1) CFU/cm(2). Thus, the cell population of 10(8.2) CFU/cm(2) was used for subsequent study. Although the bacterium was capable of growing at temperatures above and below 10°C, it could produce the pigment only at temperatures of ≥10°C. Moreover, the pigment production was faster at higher temperatures in the range of 10 to 20°C. Pigment production at various temperature patterns was well described by a new logistic model. These results suggested that the bacterium could be used in the development of a microbial temperature indicator for the low-temperature-storage management of foods and clinical materials. To our knowledge, there is no other P. agglomerans strain capable of producing a blue pigment and the pigment is a new one of microbial origin.

AtFH1 formin mutation affects actin filament and microtubule dynamics in Arabidopsis thaliana

Czech Academy of Sciences Publication Activity Database

Rosero, A.; Žárský, Viktor; Cvrčková, F.

2013-01-01

Roč. 64, č. 2 (2013), s. 585-597 ISSN 0022-0957 R&D Projects: GA ČR GAP305/10/0433 Institutional research plan: CEZ:AV0Z50380511 Keywords : Actin * Arabidopsis * At5g25500 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.794, year: 2013

Skin pigmentation kinetics after UVB exposure

DEFF Research Database (Denmark)

Ravnbak, M.H.; Philipsen, P.A.; Wiegell, S.R.

2008-01-01

There have been few previous studies of the kinetics of pigmentation following ultraviolet B (UVB) exposure, and these have included only fair-skinned persons. The current study investigated pigmentation increase to steady state and fading in 12 Scandinavians and 12 Indians/Pakistanis. Over...... a period of 3 weeks the subjects were UV-irradiated 6 times on the right side of the back and 12 times on the left side using a Solar Simulator and narrowband UVB with equal sub-Minimal Melanogenesis Doses (individually predetermined). Pigmentation was measured from skin remittance at 555 urn and 660 nm...... (allowing correction for erythema). The absolute pigmentation increase was independent of pre-exposure pigmentation, therefore the percentage pigmentation increase was higher in fair-skinned volunteers. The UV dose to minimal pigmentation was higher in darker-skinned persons for single and multiple UV...

Screening of photosynthetic pigments for herbicidal activity with a new computational molecular approach.

Science.gov (United States)

Krishnaraj, R Navanietha; Chandran, Saravanan; Pal, Parimal; Berchmans, Sheela

2013-12-01

There is an immense interest among the researchers to identify new herbicides which are effective against the herbs without affecting the environment. In this work, photosynthetic pigments are used as the ligands to predict their herbicidal activity. The enzyme 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase is a good target for the herbicides. Homology modeling of the target enzyme is done using Modeler 9.11 and the model is validated. Docking studies were performed with AutoDock Vina algorithm to predict the binding of the natural pigments such as β-carotene, chlorophyll a, chlorophyll b, phycoerythrin and phycocyanin to the target. β-carotene, phycoerythrin and phycocyanin have higher binding energies indicating the herbicidal activity of the pigments. This work reports a procedure to screen herbicides with computational molecular approach. These pigments will serve as potential bioherbicides in the future.

Chemical research on red pigments after adverse reactions to tattoo.

Science.gov (United States)

Tammaro, A; Toniolo, C; Giulianelli, V; Serafini, M; Persechino, S

2016-03-01

Currently, the incidence of tattooing is on the rise compared to the past, especially among adolescents, and it leads to the urgency of monitoring the security status of tattooing centers, as well as to inform people about the risks of tattoo practice. In our clinical experience, 20% of tattooed patients presented adverse reactions, like allergic contact dermatitis, psoriasis with Koebner's phenomena and granulomatous reactions, with the latter most prevalent and most often related to red pigment. Adverse reactions to tattoo pigments, especially the red one, are well known and described in literature. Great attention has to be focused on the pigments used, especially for the presence of new substances, often not well known. For this reason, we decided to perform a study on 12 samples of red tattoo ink, obtained by patients affected by different cutaneous reactions in the site of tattoo, to analyze their chemical composition.

Production of Monascus-like pigments

DEFF Research Database (Denmark)

2012-01-01

the cultivation medium with an inoculum of Penicillium to form a cultivation composition; d) cultivating the inoculated cultivation composition of (c); e) separating the one or more produced pigment compositions. The method of the invention may be used for producing Monascus-like pigment compositions for use......The present invention relates to a method for producing one or more Monascus-like pigment composition from Penicillium species comprising: a) providing a cultivation medium comprising a high concentration of C-and N-sources and a high C/N molar ratio, b) adjusting pH to about 5 to 8, c) inoculating...... as colouring agents in food items or non food items. The inventions further relates to Monascus-like pigment composition obtainable by a method of the inventions as well as use of the pigments....

Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill

OpenAIRE

González, Alfredo; Crittenden, Elizabeth L; García, Dana M

2004-01-01

Abstract Background In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and musc...

Pigment production from a mangrove Penicillium

African Journals Online (AJOL)

SAM

2014-06-25

Jun 25, 2014 ... Key words: Penicillium, 2-(4-acetyl phenyl) acetic acid, bio elements, salts, soluble pigment. .... Table 1. Characteristics of the pigment fractions after solvent extraction. ..... naphthoquinone pigment by Fusarium verticillioides.

Identification and hazard prediction of tattoo pigments by means of pyrolysis-gas chromatography/mass spectrometry.

Science.gov (United States)

Schreiver, Ines; Hutzler, Christoph; Andree, Sarah; Laux, Peter; Luch, Andreas

2016-07-01

The implementation of regulation for tattoo ink ingredients across Europe has generated the need for analytical methods suitable to identify prohibited compounds. Common challenges of this subject are the poor solubility and the lack of volatility for most pigments and polymers applied in tattoo inks. Here, we present pyrolysis coupled to online gas chromatography and electron impact ionization mass spectrometry (py-GC/MS) as quick and reliable tool for pigment identification using both purified pigments and tattoo ink formulations. Some 36 organic pigments frequently used in tattoo inks were subjected to py-GC/MS with the aim to establish a pyrogram library. To cross-validate pigment identification, 28 commercially available tattoo inks as well as 18 self-made pigment mixtures were analyzed. Pyrograms of inks and mixtures were evaluated by two different means to work out the most reliable and fastest strategy for an otherwise rather time-consuming data review. Using this approach, the declaration of tattoo pigments currently used on the market could be verified. The pyrolysis library presented here is also assumed suitable to predict decomposition patterns of pigments when affected by other degradation scenarios, such as sunlight exposure or laser irradiation. Thus, the consumers' risk associated with the exposure to toxicologically relevant substances that originate from pigment decomposition in the dermal layers of the skin can be assessed. Differentiation between more or less harmful pigments for this field of application now will become feasible.

A Novel Sugar Transporter from Dianthus spiculifolius, DsSWEET12, Affects Sugar Metabolism and Confers Osmotic and Oxidative Stress Tolerance in Arabidopsis.

Science.gov (United States)

Zhou, Aimin; Ma, Hongping; Feng, Shuang; Gong, Shufang; Wang, Jingang

2018-02-07

Plant SWEETs (sugars will eventually be exported transporters) play a role in plant growth and plant response to biotic and abiotic stresses. In the present study, DsSWEET12 from Dianthus spiculifolius was identified and characterized. Real-time quantitative PCR analysis revealed that DsSWEET12 expression was induced by sucrose starvation, mannitol, and hydrogen peroxide. Colocalization experiment showed that the DsSWEET12-GFP fusion protein was localized to the plasma membrane, which was labeled with FM4-64 dye, in Arabidopsis and suspension cells of D. spiculifolius . Compared to wild type plants, transgenic Arabidopsis seedlings overexpressing DsSWEET12 have longer roots and have a greater fresh weight, which depends on sucrose content. Furthermore, a relative root length analysis showed that transgenic Arabidopsis showed higher tolerance to osmotic and oxidative stresses. Finally, a sugar content analysis showed that the sucrose content in transgenic Arabidopsis was less than that in the wild type, while fructose and glucose contents were higher than those in the wild type. Taken together, our results suggest that DsSWEET12 plays an important role in seedling growth and plant response to osmotic and oxidative stress in Arabidopsis by influencing sugar metabolism.

Gamma radiation effect on Populus nigra assimilatory pigments

International Nuclear Information System (INIS)

Creanga, I. A.; Tudorie, Marcela; Mocanasu, C.; Creanga, Dorina

2002-01-01

The influence of low intensity gamma radiation on the photosynthesis in young poplar saplings was studied. Black poplar (Populus nigra) was chosen due to its ecological importance, as fast growing tree species with many hybrids, in the frame of a polluted environment. Assimilatory pigments in the leaves of irradiated saplings were assayed using standard spectrophotometric method in acetone extract. Series of five saplings formed the experimental samples. Chlorophyll a and chlorophyll b levels appeared as diminished in exposed samples in comparison to the controls. Linear regression was established in every case, the line slope showing the higher effect in chlorophyll b. Carotene pigments presented a slight increasing tendency in the exposed samples. Assimilatory pigment sum was shown to be affected by the same decreasing tendency. Student t-test was applied (two tailed, pair type) to reveal statistical significance of observed modifications. Though not very deep, the modifications induced by exposure to gamma radiation of low intensity (comparable to the local atmospheric variations, caused by both natural and artificial sources) represent putative inhibitory factors in young plant photosynthesis. The main mechanism of radiation action seems to be water radiolysis, triggering peroxide cascade, generally producing toxic products for the cell metabolism. Nevertheless, living cell ability to repair some damages caused by external stress could be revealed in the present case by the enhancing tendency of the carotenes which sustain photosynthesis as secondary pigments. (authors)

Fumed metallic oxides and conventional pigments for glossy inkjet paper

Science.gov (United States)

Lee, Hyunkook

Product development activity in the area of inkjet printing papers has accelerated greatly to meet the rapidly growing market for inkjet papers. Advancements in inkjet printing technology have also placed new demands on the paper substrate due to faster printing rates, greater resolution through increased drop volumes, and colorants added to the ink. To meet these requirements, papermakers are turning to pigmented size press formulations or pigmented coating systems. For inkjet coating applications, both the internal porosity of the pigment particles as well as the packing porosity of the coating affect print quality and dry time. Pores between the pigment particles allow for rapid diffusion of ink fluids into the coating structure, while also providing capacity for ink fluid uptake. Past research has shown the presence of coating cracks to increase the microroughness of the papers, consequently reducing the gloss of the silica/polyvinyl alcohol based coating colors. Coating cracks were not observed, at the same level of magnification, in the scanning electron microscopy images of alumina/polyvinyl alcohol coated papers. Studies are therefore needed to understand the influence of coating cracking on the microroughening of silica/polyvinyl alcohol based coatings and consequences to coating and ink gloss. Since micro roughening is known to be linked to shrinkage of the coating layer, studies are needed to determine if composite pigments can be formulated, which would enable the coating solids of the formulations to be increased to minimize the shrinkage of coating layer during drying. Coating solids greater than 55% solids are needed to reduce the difference between application solids and the coating's immobilization solids point in order to reduce shrinkage. The aim of this research was to address the above mentioned needed studies. Studies were performed to understand the influence of particle packing on gloss and ink jet print quality. Composite pigment structures

Maternal environment affects the genetic basis of seed dormancy in Arabidopsis thaliana.

Science.gov (United States)

Postma, Froukje M; Ågren, Jon

2015-02-01

The genetic basis of seed dormancy, a key life history trait important for adaptive evolution in plant populations, has yet been studied only using seeds produced under controlled conditions in greenhouse environments. However, dormancy is strongly affected by maternal environmental conditions, and interactions between seed genotype and maternal environment have been reported. Consequently, the genetic basis of dormancy of seeds produced under natural field conditions remains unclear. We examined the effect of maternal environment on the genetic architecture of seed dormancy using a recombinant inbred line (RIL) population derived from a cross between two locally adapted populations of Arabidopsis thaliana from Italy and Sweden. We mapped quantitative trait loci (QTL) for dormancy of seeds produced in the greenhouse and at the native field sites of the parental genotypes. The Italian genotype produced seeds with stronger dormancy at fruit maturation than did the Swedish genotype in all three environments, and the maternal field environments induced higher dormancy levels compared to the greenhouse environment in both genotypes. Across the three maternal environments, a total of nine dormancy QTL were detected, three of which were only detected among seeds matured in the field, and six of which showed significant QTL × maternal environment interactions. One QTL had a large effect on dormancy across all three environments and colocalized with the candidate gene DOG1. Our results demonstrate the importance of studying the genetic basis of putatively adaptive traits under relevant conditions. © 2015 John Wiley & Sons Ltd.

Hairless pigmented guinea pigs: a new model for the study of mammalian pigmentation.

Science.gov (United States)

Bolognia, J L; Murray, M S; Pawelek, J M

1990-09-01

A stock of hairless pigmented guinea pigs was developed to facilitate studies of mammalian pigmentation. This stock combines the convenience of a hairless animal with a pigmentary system that is similar to human skin. In both human and guinea pig skin, active melanocytes are located in the basal layer of the interfollicular epidermis. Hairless albino guinea pigs on an outbred Hartley background (CrI:IAF/HA(hr/hr)BR; designated hr/hr) were mated with red-haired guinea pigs (designated Hr/Hr). Red-haired heterozygotes from the F1 generation (Hr/hr) were then mated with each other or with hairless albino guinea pigs. The F2 generation included hairless pigmented guinea pigs that retained their interfollicular epidermal melanocytes and whose skin was red-brown in color. Following UV irradiation, there was an increase in cutaneous pigmentation as well as an increase in the number of active epidermal melanocytes. An additional strain of black hairless guinea pigs was developed using black Hr/Hr animals and a similar breeding scheme. These two strains should serve as useful models for studies of the mammalian pigment system.

Sensitizing pigment in the fly

International Nuclear Information System (INIS)

Vogt, K.; Kirschfeld, K.

1983-01-01

The sensitizing pigment hypothesis for the high UV sensitivity in fly photoreceptors (R1-6) is further substantiated by measurements of the polarisation sensitivity in the UV. The quantum yield of the energy transfer from sensitizing pigment to rhodopsin was estimated by electrophysiological measurements of the UV sensitivity and the rhabdomeric absorptance (at 490 nm) in individual receptor cells. The transfer efficiency is >=0.75 in receptors with an absorptance in the rhabdomeres of 0.55-0.95. This result suggests that the sensitizing pigment is bound in some way to the rhodopsin. A ratio of two molecules of sensitizing pigment per one rhodopsin is proposed. (orig.)

Raman Spectroscopy of Microbial Pigments

Science.gov (United States)

Edwards, Howell G. M.; Oren, Aharon

2014-01-01

Raman spectroscopy is a rapid nondestructive technique providing spectroscopic and structural information on both organic and inorganic molecular compounds. Extensive applications for the method in the characterization of pigments have been found. Due to the high sensitivity of Raman spectroscopy for the detection of chlorophylls, carotenoids, scytonemin, and a range of other pigments found in the microbial world, it is an excellent technique to monitor the presence of such pigments, both in pure cultures and in environmental samples. Miniaturized portable handheld instruments are available; these instruments can be used to detect pigments in microbiological samples of different types and origins under field conditions. PMID:24682303

Pseudomonas aeruginosa induces pigment production and enhances virulence in a white phenotypic variant of Staphylococcus aureus.

Science.gov (United States)

Antonic, Vlado; Stojadinovic, Alexander; Zhang, Binxue; Izadjoo, Mina J; Alavi, Mohammad

2013-01-01

Staphyloxanthin is a virulence factor which protects Staphylococcus aureus in stress conditions. We isolated two pigment variants of S. aureus and one strain of Pseudomonas aeruginosa from a single wound infection. S. aureus variants displayed white and yellow colony phenotypes. The sequence of the operons for staphyloxanthin synthesis indicated that coding and promoter regions were identical between the two pigment variants. Quorum sensing controls pigment synthesis in some bacteria. It is also shown that P. aeruginosa quorum-sensing molecules affect S. aureus transcription. We explored whether the co-infecting P. aeruginosa can affect pigment production in the white S. aureus variant. In co-culture experiments between the white variants and a selected number of Gram-positive and Gram-negative bacteria, only P. aeruginosa induced pigment production in the white variant. Gene expression analysis of the white variant did not indicate upregulation of the crtM and other genes known to be involved in pigment production (sigB, sarA, farnesyl pyrophosphate synthase gene [FPP-synthase], hfq). In contrast, transcription of the catalase gene was significantly upregulated after co-culture. P. aeruginosa-induced pigment synthesis and catalase upregulation correlated with increased resistance to polymyxin B, hydrogen peroxide, and the intracellular environment of macrophages. Our data indicate the presence of silent but functional staphyloxanthin synthesis machinery in a white phenotypic variant of S. aureus which is activated by a co-infecting P. aeruginosa via inter-species communication. Another S. aureus virulence factor, catalase is also induced by this co-infecting bacterium. The resulting phenotypic changes are directly correlated with resistance of the white variant to stressful conditions.

A Novel Sugar Transporter from Dianthus spiculifolius, DsSWEET12, Affects Sugar Metabolism and Confers Osmotic and Oxidative Stress Tolerance in Arabidopsis

Directory of Open Access Journals (Sweden)

Aimin Zhou

2018-02-01

Full Text Available Plant SWEETs (sugars will eventually be exported transporters play a role in plant growth and plant response to biotic and abiotic stresses. In the present study, DsSWEET12 from Dianthus spiculifolius was identified and characterized. Real-time quantitative PCR analysis revealed that DsSWEET12 expression was induced by sucrose starvation, mannitol, and hydrogen peroxide. Colocalization experiment showed that the DsSWEET12-GFP fusion protein was localized to the plasma membrane, which was labeled with FM4-64 dye, in Arabidopsis and suspension cells of D. spiculifolius. Compared to wild type plants, transgenic Arabidopsis seedlings overexpressing DsSWEET12 have longer roots and have a greater fresh weight, which depends on sucrose content. Furthermore, a relative root length analysis showed that transgenic Arabidopsis showed higher tolerance to osmotic and oxidative stresses. Finally, a sugar content analysis showed that the sucrose content in transgenic Arabidopsis was less than that in the wild type, while fructose and glucose contents were higher than those in the wild type. Taken together, our results suggest that DsSWEET12 plays an important role in seedling growth and plant response to osmotic and oxidative stress in Arabidopsis by influencing sugar metabolism.

Central posterior capsule pigmentation in a patient with pigment dispersion and previous ocular trauma: a case report.

Science.gov (United States)

Al-Mezaine, Hani S

2010-01-01

We report a 55-year-old man with unusually dense, unilateral central posterior capsule pigmentation associated with the characteristic clinical features of pigment dispersion syndrome, including a Krukenberg's spindle and dense trabecular pigmentation in both eyes. A history of an old blunt ocular trauma probably caused separation of the anterior hyaloid from the back of the lens, thereby creating an avenue by which pigment could reach the potential space of Berger's from the posterior chamber.

Biomass and pigments production in photosynthetic bacteria wastewater treatment: effects of light sources.

Science.gov (United States)

Zhou, Qin; Zhang, Panyue; Zhang, Guangming

2015-03-01

This study is aimed at enhancing biomass and pigments production together with pollution removal in photosynthetic bacteria (PSB) wastewater treatment via different light sources. Red, yellow, blue, white LED and incandescent lamp were used. Results showed different light sources had great effects on the PSB. PSB had the highest biomass production, COD removal and biomass yield with red LED. The corresponding biomass, COD removal and biomass yield reached 2580 mg/L, 88.6% and 0.49 mg-biomass/mg-COD-removal, respectively. The hydraulic retention time of wastewater treatment could be shortened to 72 h with red LED. Mechanism analysis showed higher ATP was produced with red LED than others. Light sources could significantly affect the pigments production. The pigments productions were greatly higher with LED than incandescent lamp. Yellow LED had the highest pigments production while red LED produced the highest carotenoid/bacteriochlorophyll ratio. Considering both efficiency and energy cost, red LED was the optimal light source. Copyright © 2014 Elsevier Ltd. All rights reserved.

Family-based linkage and association mapping reveals novel genes affecting Plum pox virus infection in Arabidopsis thaliana.

Science.gov (United States)

Pagny, Gaëlle; Paulstephenraj, Pauline S; Poque, Sylvain; Sicard, Ophélie; Cosson, Patrick; Eyquard, Jean-Philippe; Caballero, Mélodie; Chague, Aurélie; Gourdon, Germain; Negrel, Lise; Candresse, Thierry; Mariette, Stéphanie; Decroocq, Véronique

2012-11-01

Sharka is a devastating viral disease caused by the Plum pox virus (PPV) in stone fruit trees and few sources of resistance are known in its natural hosts. Since any knowledge gained from Arabidopsis on plant virus susceptibility factors is likely to be transferable to crop species, Arabidopsis's natural variation was searched for host factors essential for PPV infection. To locate regions of the genome associated with susceptibility to PPV, linkage analysis was performed on six biparental populations as well as on multiparental lines. To refine quantitative trait locus (QTL) mapping, a genome-wide association analysis was carried out using 147 Arabidopsis accessions. Evidence was found for linkage on chromosomes 1, 3 and 5 with restriction of PPV long-distance movement. The most relevant signals occurred within a region at the bottom of chromosome 3, which comprises seven RTM3-like TRAF domain-containing genes. Since the resistance mechanism analyzed here is recessive and the rtm3 knockout mutant is susceptible to PPV infection, it suggests that other gene(s) present in the small identified region encompassing RTM3 are necessary for PPV long-distance movement. In consequence, we report here the occurrence of host factor(s) that are indispensable for virus long-distance movement. © 2012 INRA. New Phytologist © 2012 New Phytologist Trust.

Sulfate as a pivotal factor in regulation of Serratia sp. strain S2B pigment biosynthesis.

Science.gov (United States)

Rastegari, Banafsheh; Karbalaei-Heidari, Hamid Reza

2016-10-01

In the present work, we investigated the prodiginine family as secondary metabolite members. Bacterial strain S2B, with the ability to produce red pigment, was isolated from the Sarcheshmeh copper mine in Iran. 16S rDNA gene sequencing revealed that the strain was placed in the Serratia genus. Pigment production was optimized using low-cost culture medium and the effects of various physicochemical factors were studied via statistical approaches. Purification of the produced pigment by silica gel column chromatography showed a strong red pigment fraction and a weaker orange band. Mass spectrometry, FT-IR spectroscopy and (1)H NMR analysis revealed that the red pigment was prodigiosin and the orange band was a prodigiosin-like analog, with molecular weights of 323 and 317 Da, respectively. Genotoxicity and cytotoxicity studies confirmed their membership in the prodiginine family. Analysis of the production pattern of the pigments in the presence of different concentrations of ammonium salts revealed the role of sulfate as an important factor in regulation of the pigment biosynthesis pathway. Overall, the data showed that regulation of the pigment biosynthesis pathway in Serratia sp. strain S2B was affected by inorganic micronutrients, particularly the sulfate ions. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Putrescine overproduction does not affect the catabolism of spermidine and spermine in poplar and Arabidopsis

Science.gov (United States)

Lin Shao; Pratiksha Bhatnagar; Rajtilak Majumdar; Rakesh Minocha; Subhash C. Minocha

2014-01-01

The effect of up-regulation of putrescine (Put) production by genetic manipulation on the turnover of spermidine (Spd) and spermine (Spm) was investigated in transgenic cells of poplar (Populus nigra x maximowiczii) and seedlings of Arabidopsis thaliana. Several-fold increase in Put production was achieved by expressing a mouse...

Gravity-regulated gene expression in Arabidopsis thaliana

Science.gov (United States)

Sederoff, Heike; Brown, Christopher S.; Heber, Steffen; Kajla, Jyoti D.; Kumar, Sandeep; Lomax, Terri L.; Wheeler, Benjamin; Yalamanchili, Roopa

Plant growth and development is regulated by changes in environmental signals. Plants sense environmental changes and respond to them by modifying gene expression programs to ad-just cell growth, differentiation, and metabolism. Functional expression of genes comprises many different processes including transcription, translation, post-transcriptional and post-translational modifications, as well as the degradation of RNA and proteins. Recently, it was discovered that small RNAs (sRNA, 18-24 nucleotides long), which are heritable and systemic, are key elements in regulating gene expression in response to biotic and abiotic changes. Sev-eral different classes of sRNAs have been identified that are part of a non-cell autonomous and phloem-mobile network of regulators affecting transcript stability, translational kinetics, and DNA methylation patterns responsible for heritable transcriptional silencing (epigenetics). Our research has focused on gene expression changes in response to gravistimulation of Arabidopsis roots. Using high-throughput technologies including microarrays and 454 sequencing, we iden-tified rapid changes in transcript abundance of genes as well as differential expression of small RNA in Arabidopsis root apices after minutes of reorientation. Some of the differentially regu-lated transcripts are encoded by genes that are important for the bending response. Functional mutants of those genes respond faster to reorientation than the respective wild type plants, indicating that these proteins are repressors of differential cell elongation. We compared the gravity responsive sRNAs to the changes in transcript abundances of their putative targets and identified several potential miRNA: target pairs. Currently, we are using mutant and transgenic Arabidopsis plants to characterize the function of those miRNAs and their putative targets in gravitropic and phototropic responses in Arabidopsis.

Incidence and severity of cavity spot of carrot as affected by pigmentation, temperature, and rainfall

Science.gov (United States)

Field trials to determine the effect of carrot pigmentation and weather parameters on cavity spot of carrot (CS) were conducted in the Holland/Bradford Marsh region of Ontario between 2002 and 2009. Twenty three colored carrots from the USDA-ARS breeding program at the University of Wisconsin (5) an...

The visual pigment cyanide effect.

Science.gov (United States)

Crescitelli, F; Karvaly, B

1989-12-01

The visual pigment of the Tokay gecko (Gekko gekko) with its in situ absorption maximum at 521 nm has its spectral position at 500 to 505 nm when chloride-deficient digitonin is used for the extraction. In this case the addition of chloride or bromide to the extract restores the maximum to 521 nm. This property, characteristic of gecko pigments in general, does not occur with any of the rhodopsins that have been tested. Simple salts of cyanide, a pseudohalogenoid with an ionic radius close to those of chloride and bromide and/or its hydrolysis product attacks both this gecko pigment and rhodopsins in the dark. This is seen as a slow thermal loss of photopigment if (sodium) cyanide is present at concentrations above 40 mM for the gecko pigment and 150 mM for the rhodopsins of the midshipman (Porichthys notatus) and of the frog (Rana pipiens). In all cases the loss of the photopigment is accompanied by the appearance of a spectral product with maximum absorption at about 340 nm. Cyanide addition has no effect on the photosensitivity of the native pigments and neither does it alter, as do chloride, bromide and other anions, the spectral absorbance curve. The spectral product at 340 nm also appears when the visual pigments are photolyzed in the presence of cyanide salts below the threshold concentrations given above. Incubation of digitonin-solubilized all-trans-retinal with (sodium) cyanide leads to a reaction product with absorption spectrum similar to that obtained with visual pigments under comparable conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

High efficiency non-viral transfection of retinal and iris pigment epithelial cells with pigment epithelium-derived factor.

Science.gov (United States)

Thumann, G; Stöcker, M; Maltusch, C; Salz, A K; Barth, S; Walter, P; Johnen, S

2010-02-01

Transplantation of pigment epithelial cells in patients with age-related macular degeneration and Parkinson's disease has the potential to improve functional rehabilitation. Genetic modification of cells before transplantation may allow the delivery of neuroprotective factors to achieve functional improvement. As transplantation of cells modified using viral vectors is complicated by the possible dissemination of viral particles and severe immune reactions, we have explored non-viral methods to insert genetic material in pigment epithelial cells. Using lipofection or nucleofection ARPE-19 cells, freshly isolated and primary retinal and iris pigment epithelial (IPE) cells were transfected with plasmids encoding green fluorescent protein (GFP) and with three plasmids encoding recombinant pigment epithelium-derived factor (PEDF) and GFP. Transfection efficiency was evaluated by fluorescence microscopy and stability of protein expression by immunoblotting. Pigment epithelial cells were successfully transfected with plasmid encoding GFP. Expression of GFP in ARPE-19 was transient, but was observed for up to 1 year in IPE cells. Analysis of pigment epithelial cells transfected with PEDF plasmids revealed that PEDF fusion proteins were successfully expressed and functionally active. In conclusion, efficient transfer of genetic information in pigment epithelial cells can be achieved using non-viral transfection protocols.

Central posterior capsule pigmentation in a patient with pigment dispersion and previous ocular trauma: A case report

Directory of Open Access Journals (Sweden)

Al-Mezaine Hani

2010-01-01

Full Text Available We report a 55-year-old man with unusually dense, unilateral central posterior capsule pigmentation associated with the characteristic clinical features of pigment dispersion syndrome, including a Krukenberg′s spindle and dense trabecular pigmentation in both eyes. A history of an old blunt ocular trauma probably caused separation of the anterior hyaloid from the back of the lens, thereby creating an avenue by which pigment could reach the potential space of Berger′s from the posterior chamber.

The genetic control of aposematic black pigmentation in hemimetabolous insects: insights from Oncopeltus fasciatus.

Science.gov (United States)

Liu, Jin; Lemonds, Thomas R; Popadić, Aleksandar

2014-09-01

Variations in body pigmentation, encompassing both the range of specific colors as well as the spatial arrangement of those colors, are among the most noticeable and lineage-specific insect features. However, the genetic mechanisms responsible for generating this diversity are still limited to several model species that are primarily holometabolous insects. To address this lack of knowledge, we utilize Oncopeltus fasciatus, an aposematic hemimetabolous insect, as a new model to study insect pigmentation. First, to determine the genetic regulation of black pigment production in Oncopeltus, we perform an RNAi analysis on three core genes involved in the melanin pathway, tyrosine hydroxylase (TH), dopa decarboxylase (DDC), and laccase 2 (lac2). The black pigmentation is affected in all instances, showing that the black pigments in this species are derived from the melanin pathway. The results of the DDC RNAi are particularly informative because they reveal that it is Dopamine melanin, not DOPA melanin, which is the predominant component of black pigments in Oncopeltus. Second, we test whether pigmentation follows a two-step model where the spatial pre-mapping of enzymatic activity is followed by vein-dependent transportation of melanin substances. We confirm the existence of the first step by observing that premature wings develop black pigmentation when exposed to melanin precursors. In addition, we provide evidence for the second step by showing that wing melanin patterning is disrupted when vein transportation is halted. These findings bring novel insights from a hemimetabolous species and establish a framework for subsequent studies on the mechanisms of pigment production and patterning responsible for variations in insect coloration. © 2014 Wiley Periodicals, Inc.

Genes of the most conserved WOX clade in plants affect root and flower development in Arabidopsis

Directory of Open Access Journals (Sweden)

Moreau Hervé

2008-10-01

Full Text Available Abstract Background The Wuschel related homeobox (WOX family proteins are key regulators implicated in the determination of cell fate in plants by preventing cell differentiation. A recent WOX phylogeny, based on WOX homeodomains, showed that all of the Physcomitrella patens and Selaginella moellendorffii WOX proteins clustered into a single orthologous group. We hypothesized that members of this group might preferentially share a significant part of their function in phylogenetically distant organisms. Hence, we first validated the limits of the WOX13 orthologous group (WOX13 OG using the occurrence of other clade specific signatures and conserved intron insertion sites. Secondly, a functional analysis using expression data and mutants was undertaken. Results The WOX13 OG contained the most conserved plant WOX proteins including the only WOX detected in the highly proliferating basal unicellular and photosynthetic organism Ostreococcus tauri. A large expansion of the WOX family was observed after the separation of mosses from other land plants and before monocots and dicots have arisen. In Arabidopsis thaliana, AtWOX13 was dynamically expressed during primary and lateral root initiation and development, in gynoecium and during embryo development. AtWOX13 appeared to affect the floral transition. An intriguing clade, represented by the functional AtWOX14 gene inside the WOX13 OG, was only found in the Brassicaceae. Compared to AtWOX13, the gene expression profile of AtWOX14 was restricted to the early stages of lateral root formation and specific to developing anthers. A mutational insertion upstream of the AtWOX14 homeodomain sequence led to abnormal root development, a delay in the floral transition and premature anther differentiation. Conclusion Our data provide evidence in favor of the WOX13 OG as the clade containing the most conserved WOX genes and established a functional link to organ initiation and development in Arabidopsis, most

Arsenic triggers the nitric oxide (NO) and S-nitrosoglutathione (GSNO) metabolism in Arabidopsis

International Nuclear Information System (INIS)

Leterrier, Marina; Airaki, Morad; Palma, José M.; Chaki, Mounira; Barroso, Juan B.; Corpas, Francisco J.

2012-01-01

Environmental contamination by arsenic constitutes a problem in many countries, and its accumulation in food crops may pose health complications for humans. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are involved at various levels in the mechanism of responding to environmental stress in higher plants. Using Arabidopsis seedlings exposed to different arsenate concentrations, physiological and biochemical parameters were analyzed to determine the status of ROS and RNS metabolisms. Arsenate provoked a significant reduction in growth parameters and an increase in lipid oxidation. These changes were accompanied by an alteration in antioxidative enzymes and the nitric oxide (NO) metabolism, with a significant increase in NO content, S-nitrosoglutathione reductase (GSNOR) activity and protein tyrosine nitration as well as a concomitant reduction in glutathione and S-nitrosoglutathione (GSNO) content. Our results indicate that 500 μM arsenate (AsV) causes nitro-oxidative stress in Arabidopsis, being the glutathione reductase and the GSNOR activities clearly affected. - Highlights: ► In Arabidopsis, arsenate provokes damages in the membrane integrity of root cells. ► As induces an oxidative stress according to an increase in lipid oxidation. ► NO content and protein tyrosine nitration increases under arsenate stress. ► Arsenate provokes a reduction of GSH, GSSG and GSNO content. ► Arsenate induces a nitro-oxidative stress in Arabidopsis. - Arsenic stress affects nitric oxide (NO) and glutathione (GSH) metabolism which provokes a nitro-oxidative stress.

Plasma membrane lipid–protein interactions affect signaling processes in sterol-biosynthesis mutants in Arabidopsis thaliana

Science.gov (United States)

Zauber, Henrik; Burgos, Asdrubal; Garapati, Prashanth; Schulze, Waltraud X.

2014-01-01

The plasma membrane is an important organelle providing structure, signaling and transport as major biological functions. Being composed of lipids and proteins with different physicochemical properties, the biological functions of membranes depend on specific protein–protein and protein–lipid interactions. Interactions of proteins with their specific sterol and lipid environment were shown to be important factors for protein recruitment into sub-compartmental structures of the plasma membrane. System-wide implications of altered endogenous sterol levels for membrane functions in living cells were not studied in higher plant cells. In particular, little is known how alterations in membrane sterol composition affect protein and lipid organization and interaction within membranes. Here, we conducted a comparative analysis of the plasma membrane protein and lipid composition in Arabidopsis sterol-biosynthesis mutants smt1 and ugt80A2;B1. smt1 shows general alterations in sterol composition while ugt80A2;B1 is significantly impaired in sterol glycosylation. By systematically analyzing different cellular fractions and combining proteomic with lipidomic data we were able to reveal contrasting alterations in lipid–protein interactions in both mutants, with resulting differential changes in plasma membrane signaling status. PMID:24672530

Nitric oxide-dependent pigment migration induced by ultraviolet radiation in retinal pigment cells of the crab Neohelice granulata.

Science.gov (United States)

Filgueira, Daza de Moraes Vaz Batista; Guterres, Laís Pereira; Votto, Ana Paula de Souza; Vargas, Marcelo Alves; Boyle, Robert Tew; Trindade, Gilma Santos; Nery, Luiz Eduardo Maia

2010-01-01

The purpose of this study was to verify the occurrence of pigment dispersion in retinal pigment cells exposed to UVA and UVB radiation, and to investigate the possible participation of a nitric oxide (NO) pathway. Retinal pigment cells from Neohelice granulata were obtained by cellular dissociation. Cells were analyzed for 30 min in the dark (control) and then exposed to 1.1 and 3.3 J cm(-2) UVA, 0.07 and 0.9 J cm(-2) UVB, 20 nmβ-PDH (pigment dispersing hormone) or 10 μm SIN-1 (NO donor). Histological analyses were performed to verify the UV effect in vivo. Cultured cells were exposed to 250 μm L-NAME (NO synthase blocker) and afterwards were treated with UVA, UVB or β-PDH. The retinal cells in culture displayed significant pigment dispersion in response to UVA, UVB and β-PDH. The same responses to UVA and UVB were observed in vivo. SIN-1 did not induce pigment dispersion in the cell cultures. L-NAME significantly decreased the pigment dispersion induced by UVA and UVB but not by β-PDH. All retinal cells showed an immunopositive reaction against neuronal nitric oxide synthases. Therefore, UVA and UVB radiation are capable of inducing pigment dispersion in retinal pigment cells of Neohelice granulata and this dispersion may be nitric oxide synthase dependent. © 2010 The Authors. Journal Compilation. The American Society of Photobiology.

State of art in research of ceramic pigments

International Nuclear Information System (INIS)

Sulcova, P.; Trojan, M.

2004-01-01

The research of our laboratory is focused on investigation of special inorganic pigments, mainly on ceramic pigments. many pigments used just now are questionable from the hygienic point of view. The fact that the most of the pigments contain problematic elements opens necessity of substitution of pigments containing toxic metals (chromium). Yellow ceramic pigments commonly used such as Pb 2 Sb 2 O 7 , PbCrO 4 and CdS are now being expelled from the market because of their toxicity. For this reason the main attention has been directed to the synthesis of new inorganic compounds mainly with yellow, orange and red colour hues, which can be used as pigments for colouring of glaze, plastics or building materials. In harmony with this postulate the pigments based on CeO 2 represent new special inorganic pigments with high-temperature stability have been synthesized. The commercial significance is in thermal, chemical and light stability, combined with their low toxicity. (author)

Pigment signatures of phytoplankton communities in the Beaufort Sea

Science.gov (United States)

Coupel, P.; Matsuoka, A.; Ruiz-Pino, D.; Gosselin, M.; Marie, D.; Tremblay, J.-É.; Babin, M.

2015-02-01

Phytoplankton are expected to respond to recent environmental changes of the Arctic Ocean. In terms of bottom-up control, modifying the phytoplankton distribution will ultimately affect the entire food web and carbon export. However, detecting and quantifying changes in phytoplankton communities in the Arctic Ocean remains difficult because of the lack of data and the inconsistent identification methods used. Based on pigment and microscopy data sampled in the Beaufort Sea during summer 2009, we optimized the chemotaxonomic tool CHEMTAX (CHEMical TAXonomy) for the assessment of phytoplankton community composition in an Arctic setting. The geographical distribution of the main phytoplankton groups was determined with clustering methods. Four phytoplankton assemblages were determined and related to bathymetry, nutrients and light availability. Surface waters across the whole survey region were dominated by prasinophytes and chlorophytes, whereas the subsurface chlorophyll maximum was dominated by the centric diatoms Chaetoceros socialis on the shelf and by two populations of nanoflagellates in the deep basin. Microscopic counts showed a high contribution of the heterotrophic dinoflagellates Gymnodinium and Gyrodinium spp. to total carbon biomass, suggesting high grazing activity at this time of the year. However, CHEMTAX was unable to detect these dinoflagellates because they lack peridinin. In heterotrophic dinoflagellates, the inclusion of the pigments of their prey potentially leads to incorrect group assignments and some misinterpretation of CHEMTAX. Thanks to the high reproducibility of pigment analysis, our results can serve as a baseline to assess change and spatial or temporal variability in several phytoplankton populations that are not affected by these misinterpretations.

Synthesis of new environment-friendly yellow pigments

International Nuclear Information System (INIS)

Furukawa, Shinya; Masui, Toshiyuki; Imanaka, Nobuhito

2006-01-01

New inorganic pigments based on amorphous cerium tungstate, Ce 1-x M x W 2 O 8 (M = Zr or Ti, 0 ≤ x ≤ 0.6), were synthesized and their color properties were characterized from the viewpoint of possible ecological inorganic pigments. The Ce 1-x M x W 2 O 8 materials absorb the visible and the ultraviolet light under 500 nm efficiently, which is originated in the O 2p -Ce 4f and the O 2p -W 5d double charge transfer transitions, and, as a result, the pigments can show a brilliant yellow color. The optical absorption edge wavelength of these pigments depends on the Zr or Ti content, and the effective yellow hue was observed at x = 0.2 for both pigments. The color properties of the present pigments suggest that they have a potential to be applied as a satisfactory pigment for paints. Furthermore, these pigments can be prepared by a simple co-precipitation method. They are inert and safe and do not produce side effects in the human body because they are composed of non-toxic and safe elements

GmGBP1, a homolog of human ski interacting protein in soybean, regulates flowering and stress tolerance in Arabidopsis

Directory of Open Access Journals (Sweden)

Zhang Yanwei

2013-02-01

Full Text Available Abstract Background SKIP is a transcription cofactor in many eukaryotes. It can regulate plant stress tolerance in rice and Arabidopsis. But the homolog of SKIP protein in soybean has been not reported up to now. Results In this study, the expression patterns of soybean GAMYB binding protein gene (GmGBP1 encoding a homolog of SKIP protein were analyzed in soybean under abiotic stresses and different day lengths. The expression of GmGBP1 was induced by polyethyleneglycol 6000, NaCl, gibberellin, abscisic acid and heat stress. GmGBP1 had transcriptional activity in C-terminal. GmGBP1 could interact with R2R3 domain of GmGAMYB1 in SKIP domain to take part in gibberellin flowering pathway. In long-day (16 h-light condition, transgenic Arabidopsis with the ectopic overexpression of GmGBP1 exhibited earlier flowering and less number of rosette leaves; Suppression of AtSKIP in Arabidopsis resulted in growth arrest, flowering delay and down-regulation of many flowering-related genes (CONSTANS, FLOWERING LOCUS T, LEAFY; Arabidopsis myb33 mutant plants with ectopic overexpression of GmGBP1 showed the same flowering phenotype with wild type. In short-day (8 h-light condition, transgenic Arabidopsis plants with GmGBP1 flowered later and showed a higher level of FLOWERING LOCUS C compared with wild type. When treated with abiotic stresses, transgenic Arabidopsis with the ectopic overexpression of GmGBP1 enhanced the tolerances to heat and drought stresses but reduced the tolerance to high salinity, and affected the expressions of several stress-related genes. Conclusions In Arabidopsis, GmGBP1 might positively regulate the flowering time by affecting CONSTANS, FLOWERING LOCUS T, LEAFY and GAMYB directly or indirectly in photoperiodic and gibberellin pathways in LDs, but GmGBP1 might represse flowering by affecting FLOWERING LOCUS C and SHORT VEGETATIVE PHASE in autonomous pathway in SDs. GmGBP1 might regulate the activity of ROS-eliminating to improve the

Swapping one red pigment for another.

Science.gov (United States)

Davies, Kevin M

2015-01-01

Betalains are bright red and yellow pigments, which are produced in only one order of plants, the Caryophyllales, and replace the more familiar anthocyanin pigments. The evolutionary origin of betalain production is a mystery, but a new study has identified the first regulator of betalain production and discovered a previously unknown link between the two pigment pathways.

Comparison of chemical changes during photooxidation of polypropylene film and filament containing phthalocyanine pigment

International Nuclear Information System (INIS)

Ahmadi, Z.; Haghighat Kish, M.; Kotak, R.; Katbab, A. A.

2008-01-01

Photooxidation as an important process, which significantly affects the service life of the polypropylene products, has been the subject of much theoretical and experimental study. Pigments used often change the light stabilities of polypropylene. Out-door applications of pigmented polypropylene are now increasingly developed in products such as artificial grass. The aim of this work is to examine the effect of photo-oxidation on the structure of isotactic polypropylene (iPP) in film and filament forms, where phthalocyanine pigment is used. For production of films and filaments, iPP granules with MFI 25 g/10 min were used, with and without phthalocyanine pigment. Samples were exposed to xenon lamp for various time lengths. The extent of the changes in chemical and structural parameters was examined by differential scanning calorimetry, Fourier transform infrared spectroscopy and wide angle x-ray diffraction. The results show that carbonyl and hydroperoxide indices increase during the exposure to the radiation. The changes in melting points of the samples were not significant after irradiation process. The effects of phthalocyanine pigment in the photooxidation of film and filament were different. Crystalline fractions of the non-pigmented filament samples decreased during the irradiation time while increased in film samples. Build up of hydroperoxide and carbonyl group in filament was higher than in film samples; that could be due to the differences in structural parameters. Crystallinity variations during photooxidation are related to the nucleation effect of the pigment, chemical crystallization and phase transformation

Comparison of Chemical Changes During Photooxidation of Polypropylene Film and Filament Containing Phthalocyanine Pigment

Directory of Open Access Journals (Sweden)

Z. Ahmadi

2008-02-01

Full Text Available Photooxidation as an important process, which significantly affects the service life of the polypropylene products, has been the subject of much theoretical and experimental study. Pigments used often change the light stabilities of polypropylene. Out-door applications of pigmented polypr-opylene are now increasingly developed in products such as artificial grass. The aim of this work is to examine the effect of photo-oxidation on the structure of isotactic polypropylene (iPP in film and filament forms, where phthalocyanine pigment is used. For production of films and filaments, iPP granules with MFI 25 g/10min were used, with and without phthalocyanine pigment. Samples were exposed to xenon lamp for various time lengths. The extent of the changes in chemical and structural parameters was examined by differential scanning calorimetry, Fourier transform infrared spectroscopy and wide angle x-ray diffraction. The results show that carbonyl and hydroperoxide indices increase during the exposure to the radiation. The changes in melting points of the samples were not significant after irradiation process. The effects of phthalocyanine pigment in the photooxidation of filmand filament were different. Crystalline fractions of the non-pigmented filament samples decreased during the irradiation time while increased in film samples. Build up of hydroperoxide and carbonyl group in filament was higher than in film samples; that could be due to the differences in structural parameters. Crystallinity variations during photooxidation are related to the nucleation effect of the pigment, chemical crystallization and phase transformation.

Modification of cadmium pigments for colouring of polyolefins

International Nuclear Information System (INIS)

Kalinskaya, T.V.; Livshits, I.M.

1976-01-01

Modification conditions are studied of cadmium pigments, obtained by different methods, aliphatic acids(C 5 , C 8 and C 17 ). It is found, that cadmium pigments can adsorb acids with the number of atoms of carbon not less than 8. Stearic acid adsorption on lemon cadmium pigment taken as an example has shown the efficiency of pigment modification influence on its dispersancy in non-polar medium. Modification of yellow cadmium pigments of stearic acid makes possible to obtain pigment output forms ensuring a good particle distribution during polyolefine colouring

Photosynthesis, chlorophyll fluorescence, light-harvesting system and photoinhibition resistance of a zeaxanthin-accumulating mutant of Arabidopsis thaliana.

Science.gov (United States)

Tardy, F; Havaux, M

1996-06-01

The abscisic-acid-deficient aba-1 mutant of Arabidopsis thaliana is unable to epoxidize zeaxanthin. As a consequence, it contains large amounts of this carotenoid and lacks epoxy-xanthophylls. HPLC analysis of pigment contents in leaves, isolated thylakoids and preparations of the major light-harvesting complex of photosystem II (PSII) (LHC-II) indicated that zeaxanthin replaced neoxanthin, violaxanthin and antheraxanthin in the light-harvesting system of PSII in aba-1. Non-denaturing electrophoretic fractionation of solubilized thylakoids showed that the xanthophyll imbalance in aba-1 was associated with a pronounced decrease in trimeric LHC-II in favour of monomeric complexes, with a substantial increase in free pigments (mainly zeaxanthin and chlorophyll b), suggesting a decreased stability of LHC-II. The reduced thermostability of PSII in aba-1 was also deduced from in vivo chlorophyll fluorescence measurements. Wild-type and aba-1 leaves could not be distinguished on the basis of their photosynthetic performance: no significant difference was observed between the two types of leaves for light-limited and light-saturated photosynthetic oxygen evolution, PSII photochemistry and PSII to PSI electron flow. When dark-adapted leaves (grown in white light of 80 mumol m-2s-1) were suddenly exposed to red light of 150 mumol m-2s-1, there was a strong nonphotochemical quenching of chlorophyll fluorescence, the amplitude of which was virtually identical (at steady state) in aba-1 and wild-type leaves, despite the fact that the xanthophyll cycle pigment pool was completely in the form of zeaxanthin in aba-1 and almost exclusively in the form of violaxanthin in the wild type. A high concentration of zeaxanthin in aba-1 thylakoids did not, in itself, provide any particular protection against the photoinhibition of PSII. Taken together, the presented results indicate the following: (1) zeaxanthin can replace epoxy-xanthophylls in LHC-II without significantly affecting the

Effect of solar radiation on photosynthesis and pigmentation in the cyanobacterium microcoleus chtihonoplastes

International Nuclear Information System (INIS)

Annan, J.N.; Galyuon, I. K. A.; Donkor, V.A.

2007-01-01

The effects of solar radiation on the photosynthetic oxygen production and pigmentation were investigated in the marine filamentous cyanobacterium. Microcoleus chthonoplastes harvested from the intertidal zone of the Biriwa coast in Ghana. The organism was exposed to unfiltered solar radiation (UV-B. UV-A and PAR) and solar radiation filtered through optical filters. WG320 (UV-A and PAR), GG400 (PAR only), and UG5 (only UV-B and UV-A), Photosynthetic oxygen production was impaired. The reduction in the rate of photosynthetic oxygen production took over 2 hours to occur. The photoinhibition due to unfiltered solar radiation and combined UV-A and PAR were most severe. Absorption spectra of the crude extracts of M. chthonoplastes, indicated the presence of chlorophyll a, carotenoids, phycoerythrin and phycocyanin as the photosynthetic pigments, which were significantly bleached under the various solar radiation wavelengths. Generally, the phycobilins were affected most. Fluorescence measurements showed peaks that decreased significantly in amplitude and also underwent a shift towards shorter wavelengths, with prolonged exposure time, indicating that energy transfer from the accessory pigments was adversely affected. The implication is that increased solar radiation may have severe consequences on the marine ecosystem. (au)

Arabidopsis flower specific defense gene expression patterns affect resistance to pathogens

KAUST Repository

Ederli, Luisa

2015-02-20

We investigated whether the Arabidopsis flower evolved protective measures to increase reproductive success. Firstly, analyses of available transcriptome data show that the most highly expressed transcripts in the closed sepal (stage 12) are enriched in genes with roles in responses to chemical stimuli and cellular metabolic processes. At stage 15, there is enrichment in transcripts with a role in responses to biotic stimuli. Comparative analyses between the sepal and petal in the open flower mark an over-representation of transcripts with a role in responses to stress and catalytic activity. Secondly, the content of the biotic defense-associated phytohormone salicylic acid (SA) in sepals and petals is significantly higher than in leaves. To understand whether the high levels of stress responsive transcripts and the higher SA content affect defense, wild-type plants (Col-0) and transgenic plants defective in SA accumulation (nahG) were challenged with the biotrophic fungus Golovinomyces cichoracearum, the causal agent of powdery mildew, and the necrotrophic fungus Botrytis cinerea. NahG leaves were more sensitive than those of Col-0, suggesting that in leaves SA has a role in the defense against biotrophs. In contrast, sepals and petals of both genotypes were resistant to G. cichoracearum, indicating that in the flower, resistance to the biotrophic pathogen is not critically dependent on SA, but likely dependent on the up-regulation of stress-responsive genes. Since sepals and petals of both genotypes are equally susceptible to B. cinerea, we conclude that neither stress-response genes nor increased SA accumulation offers protection against the necrotrophic pathogen. These results are interpreted in the light of the distinctive role of the flower and we propose that in the early stages, the sepal may act as a chemical defense barrier of the developing reproductive structures against biotrophic pathogens.

Effects of Depilation-Induced Skin Pigmentation and Diet-Induced Fluorescence on In Vivo Fluorescence Imaging

OpenAIRE

Kwon, Sunkuk; Sevick-Muraca, Eva M.

2017-01-01

Near-infrared fluorescence imaging (NIRFI) and far-red fluorescence imaging (FRFI) were used to investigate effects of depilation-induced skin pigmentation and diet-induced background fluorescence on fluorescent signal amplitude and lymphatic contraction frequency in C57BL6 mice. Far-red fluorescent signal amplitude, but not frequency, was affected by diet-induced fluorescence, which was removed by feeding the mice an alfalfa-free diet, and skin pigmentation further impacted the amplitude mea...

Effects of ultraviolet radiation, visible light, and infrared radiation on erythema and pigmentation: a review.

Science.gov (United States)

Sklar, Lindsay R; Almutawa, Fahad; Lim, Henry W; Hamzavi, Iltefat

2013-01-01

The effects of ultraviolet radiation, visible light, and infrared radiation on cutaneous erythema, immediate pigment darkening, persistent pigment darkening, and delayed tanning are affected by a variety of factors. Some of these factors include the depth of cutaneous penetration of the specific wavelength, the individual skin type, and the absorption spectra of the different chromophores in the skin. UVB is an effective spectrum to induce erythema, which is followed by delayed tanning. UVA induces immediate pigment darkening, persistent pigment darkening, and delayed tanning. At high doses, UVA (primarily UVA2) can also induce erythema in individuals with skin types I-II. Visible light has been shown to induce erythema and a tanning response in dark skin, but not in fair skinned individuals. Infrared radiation produces erythema, which is probably a thermal effect. In this article we reviewed the available literature on the effects of ultraviolet radiation, visible light, and infrared radiation on the skin in regards to erythema and pigmentation. Much remains to be learned on the cutaneous effects of visible light and infrared radiation.

Hemoglobin is essential for normal growth of Arabidopsis organs

DEFF Research Database (Denmark)

Hebelstrup, Kim Henrik; Hunt, Peter; Dennis, Elizabeth

2006-01-01

In Arabidopsis thaliana, the class I hemoglobin AHb1 is transiently expressed in the hydathodes of leaves and in floral buds from young inflorescences. Nitric oxide (NO) accumulates to high levels in these organs when AHb1 is silenced, indicating an important role in metabolizing NO. AHb1-silence...... suggests that 3-on-3 hemoglobins apart from a role in hypoxic stress play a general role under non-stressed conditions where they are essential for normal development by controlling the level of NO which tends to accumulate in floral buds and leaf hydathodes of plants......In Arabidopsis thaliana, the class I hemoglobin AHb1 is transiently expressed in the hydathodes of leaves and in floral buds from young inflorescences. Nitric oxide (NO) accumulates to high levels in these organs when AHb1 is silenced, indicating an important role in metabolizing NO. AHb1-silenced...... lines are viable but show a mutant phenotype affecting the regions where AHb1 is expressed. Arabidopsis lines with an insertional knockout or overexpression of AHb2, a class II 3-on-3 hemoglobin, were generated. Seedlings overexpressing AHb2 show enhanced survival of hypoxic stress. The AHb2 knockout...

Rhizosphere Microbial Community Composition Affects Cadmium and Zinc Uptake by the Metal-Hyperaccumulating Plant Arabidopsis halleri

Science.gov (United States)

Muehe, E. Marie; Weigold, Pascal; Adaktylou, Irini J.; Planer-Friedrich, Britta; Kraemer, Ute; Kappler, Andreas

2015-01-01

The remediation of metal-contaminated soils by phytoextraction depends on plant growth and plant metal accessibility. Soil microorganisms can affect the accumulation of metals by plants either by directly or indirectly stimulating plant growth and activity or by (im)mobilizing and/or complexing metals. Understanding the intricate interplay of metal-accumulating plants with their rhizosphere microbiome is an important step toward the application and optimization of phytoremediation. We compared the effects of a “native” and a strongly disturbed (gamma-irradiated) soil microbial communities on cadmium and zinc accumulation by the plant Arabidopsis halleri in soil microcosm experiments. A. halleri accumulated 100% more cadmium and 15% more zinc when grown on the untreated than on the gamma-irradiated soil. Gamma irradiation affected neither plant growth nor the 1 M HCl-extractable metal content of the soil. However, it strongly altered the soil microbial community composition and overall cell numbers. Pyrosequencing of 16S rRNA gene amplicons of DNA extracted from rhizosphere samples of A. halleri identified microbial taxa (Lysobacter, Streptomyces, Agromyces, Nitrospira, “Candidatus Chloracidobacterium”) of higher relative sequence abundance in the rhizospheres of A. halleri plants grown on untreated than on gamma-irradiated soil, leading to hypotheses on their potential effect on plant metal uptake. However, further experimental evidence is required, and wherefore we discuss different mechanisms of interaction of A. halleri with its rhizosphere microbiome that might have directly or indirectly affected plant metal accumulation. Deciphering the complex interactions between A. halleri and individual microbial taxa will help to further develop soil metal phytoextraction as an efficient and sustainable remediation strategy. PMID:25595759

Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens.

Science.gov (United States)

de Ondarza, José

2017-01-01

Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia 's virulence genes and defenses is therefore valuable. Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 - 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H 2 O 2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens .

Carbachol-mediated pigment granule dispersion in retinal pigment epithelium requires Ca2+ and calcineurin.

Science.gov (United States)

Johnson, Adam S; García, Dana M

2007-12-19

Inside bluegill (Lepomis macrochirus) retinal pigment epithelial cells, pigment granules move in response to extracellular signals. During the process of aggregation, pigment motility is directed toward the cell nucleus; in dispersion, pigment is directed away from the nucleus and into long apical processes. A number of different chemicals have been found to initiate dispersion, and carbachol (an acetylcholine analog) is one example. Previous research indicates that the carbachol-receptor interaction activates a Gq-mediated pathway which is commonly linked to Ca2+ mobilization. The purpose of the present study was to test for involvement of calcium and to probe calcium-dependent mediators to reveal their role in carbachol-mediated dispersion. Carbachol-induced pigment granule dispersion was blocked by the calcium chelator BAPTA. In contrast, the calcium channel antagonist verapamil, and incubation in Ca2+-free medium failed to block carbachol-induced dispersion. The calcineurin inhibitor cypermethrin blocked carbachol-induced dispersion; whereas, two protein kinase C inhibitors (staurosporine and bisindolylmaleimide II) failed to block carbachol-induced dispersion, and the protein kinase C activator phorbol 12-myristate 13-acetate failed to elicit dispersion. A rise in intracellular calcium is necessary for carbachol-induced dispersion; however, the Ca2+ requirement is not dependent on extracellular sources, implying that intracellular stores are sufficient to enable pigment granule dispersion to occur. Calcineurin is a likely Ca2+-dependent mediator involved in the signal cascade. Although the pathway leads to the generation of diacylglycerol and calcium (both required for the activation of certain PKC isoforms), our evidence does not support a significant role for PKC.

Mutations affecting the radial organisation of the Arabidopsis root display specific defects throughout the embryonic axis

NARCIS (Netherlands)

Scheres, B.J.G.; Di Laurenzio, L.; Willemsen, V.; Hauser, M.-T.; Janmaat, K.; Benfey, P.N.

1995-01-01

The primary root of Arabidopsis thaliana has a remarkably uniform cellular organisation. The fixed radial pattern of cell types in the mature root arises from proliferative divisions within the root meristem. The root meristem, in turn, is laid down during embryogenesis. We have analysed six

Characterization of green seed, an enchancer of abi3-1 in Arabidopsis that affects seed longevity

NARCIS (Netherlands)

Clerkx, E.J.M.; Vries, de M.H.C.; Ruijs, G.J.; Groot, S.P.C.; Koornneef, M.

2003-01-01

Seeds are usually stored in physiological conditions in which they gradually lose their viability and vigor depending on storage conditions, storage time, and genotype. Very little is known about the underlying genetics of seed storability and seed deterioration. We analyzed a mutant in Arabidopsis

Production of Monascus-like pigments

DEFF Research Database (Denmark)

2012-01-01

The present invention relates to a method for producing one or more Monascus-like pigment composition from Penicillium species comprising: a) providing a cultivation medium comprising a high concentration of C-and N-sources and a high C/N molar ratio, b) adjusting pH to about 5 to 8, c) inoculati...... as colouring agents in food items or non food items. The inventions further relates to Monascus-like pigment composition obtainable by a method of the inventions as well as use of the pigments....

Depletion of Arabidopsis SC35 and SC35-like serine/arginine-rich proteins affects the transcription and splicing of a subset of genes.

Science.gov (United States)

Yan, Qingqing; Xia, Xi; Sun, Zhenfei; Fang, Yuda

2017-03-01

Serine/arginine-rich (SR) proteins are important splicing factors which play significant roles in spliceosome assembly and splicing regulation. However, little is known regarding their biological functions in plants. Here, we analyzed the phenotypes of mutants upon depleting different subfamilies of Arabidopsis SR proteins. We found that loss of the functions of SC35 and SC35-like (SCL) proteins cause pleiotropic changes in plant morphology and development, including serrated leaves, late flowering, shorter roots and abnormal silique phyllotaxy. Using RNA-seq, we found that SC35 and SCL proteins play roles in the pre-mRNA splicing. Motif analysis revealed that SC35 and SCL proteins preferentially bind to a specific RNA sequence containing the AGAAGA motif. In addition, the transcriptions of a subset of genes are affected by the deletion of SC35 and SCL proteins which interact with NRPB4, a specific subunit of RNA polymerase II. The splicing of FLOWERING LOCUS C (FLC) intron1 and transcription of FLC were significantly regulated by SC35 and SCL proteins to control Arabidopsis flowering. Therefore, our findings provide mechanistic insight into the functions of plant SC35 and SCL proteins in the regulation of splicing and transcription in a direct or indirect manner to maintain the proper expression of genes and development.

Pigments in Extra-Virgin Olive Oils Produced in Tuscany (Italy) in Different Years

Science.gov (United States)

Lazzerini, Cristina; Domenici, Valentina

2017-01-01

Pigments are responsible for the color of olive oils, and are an important ingredient that is directly related to the quality of this food. However, the concentration of pigments can vary significantly depending on the climate conditions, harvesting time, and olive cultivars. In this work, we quantified the main pigments in several extra-virgin olive oils produced from a blend of three cultivars (Moraiolo, Frantoio, and Leccino) typical of Tuscany (Italy) harvested in three different years: 2012, 2013, and 2014. Pigments—namely, β-carotene, lutein, pheophytin A, and pheophytin B—were quantified by a method based on the mathematical analysis of the near ultraviolet-visible absorption spectra of the oils. Data were analyzed by a multivariate statistical approach. The results show that the pigments’ content of extra-virgin olive oils produced in 2014 can be well distinguished with respect to previous years. This can be explained by the anomalous climate conditions, which strongly affected Italy and, in particular, Tuscany, where the olives were harvested. This study represents an interesting example of how pigment content can be significant in characterizing olive oils. Moreover, this is the first report of pigment quantification in extra-virgin olive oils produced in Tuscany. PMID:28353651

Supercritical carbon dioxide extraction of pigments from Bixa orellana seeds (experiments and modeling

Directory of Open Access Journals (Sweden)

B. P. Nobre

2006-06-01

Full Text Available Supercritical CO2 extraction of the pigments from Bixa orellana seeds was carried out in a flow apparatus at a pressure of 200 bar and a temperature of 40 ºC at two fluid flow rates (0.67g/min and 1.12g/min. The efficiency of the extraction was low (only about 1% of the pigment was extracted. The increase in flow rate led to a decrease in pigment recovery. A large increase in recovery (from 1% to 45% was achieved using supercritical carbon dioxide with 5 mol % ethanol as extraction fluid at pressures of 200 and 300 bar and temperatures of 40 and 60 ºC. Although the increase in temperature and pressure led to an increase in recovery, the changes in flow rate did not seem to affect it. Furthermore, two plug flow models were applied to describe the supercritical extraction of the pigments from annatto seeds. Mass transfer coefficients were determined and compared well with those obtained by other researchers with similar models for the supercritical extraction of solutes from plant materials.

Crystalline Organic Pigment-Based Field-Effect Transistors.

Science.gov (United States)

Zhang, Haichang; Deng, Ruonan; Wang, Jing; Li, Xiang; Chen, Yu-Ming; Liu, Kewei; Taubert, Clinton J; Cheng, Stephen Z D; Zhu, Yu

2017-07-05

Three conjugated pigment molecules with fused hydrogen bonds, 3,7-diphenylpyrrolo[2,3-f]indole-2,6(1H,5H)-dione (BDP), (E)-6,6'-dibromo-[3,3'-biindolinylidene]-2,2'-dione (IIDG), and 3,6-di(thiophen-2-yl)-2,5-dihydropyrrolo-[3,4-c]pyrrole-1,4-dione (TDPP), were studied in this work. The insoluble pigment molecules were functionalized with tert-butoxylcarbonyl (t-Boc) groups to form soluble pigment precursors (BDP-Boc, IIDG-Boc, and TDPP-Boc) with latent hydrogen bonding. The single crystals of soluble pigment precursors were obtained. Upon simple thermal annealing, the t-Boc groups were removed and the soluble pigment precursor molecules with latent hydrogen bonding were converted into the original pigment molecules with fused hydrogen bonding. Structural analysis indicated that the highly crystalline soluble precursors were directly converted into highly crystalline insoluble pigments, which are usually only achievable by gas-phase routes like physical vapor transport. The distinct crystal structure after the thermal annealing treatment suggests that fused hydrogen bonding is pivotal for the rearrangement of molecules to form a new crystal in solid state, which leads to over 2 orders of magnitude enhancement in charge mobility in organic field-effect transistor (OFET) devices. This work demonstrated that crystalline OFET devices with insoluble pigment molecules can be fabricated by their soluble precursors. The results indicated that a variety of commercially available conjugated pigments could be potential active materials for high-performance OFETs.

GDP-D-mannose epimerase regulates male gametophyte development, plant growth and leaf senescence in Arabidopsis.

Science.gov (United States)

Qi, Tiancong; Liu, Zhipeng; Fan, Meng; Chen, Yan; Tian, Haixia; Wu, Dewei; Gao, Hua; Ren, Chunmei; Song, Susheng; Xie, Daoxin

2017-09-04

Plant GDP-D-mannose epimerase (GME) converts GDP-D-mannose to GDP-L-galactose, a precursor of both L-ascorbate (vitamin C) and cell wall polysaccharides. However, the genetic functions of GME in Arabidopsis are unclear. In this study, we found that mutations in Arabidopsis GME affect pollen germination, pollen tube elongation, and transmission and development of the male gametophyte through analysis of the heterozygous GME/gme plants and the homozygous gme plants. Arabidopsis gme mutants also exhibit severe growth defects and early leaf senescence. Surprisingly, the defects in male gametophyte in the gme plants are not restored by L-ascorbate, boric acid or GDP-L-galactose, though boric acid rescues the growth defects of the mutants, indicating that GME may regulate male gametophyte development independent of L-ascorbate and GDP-L-galactose. These results reveal key roles for Arabidopsis GME in reproductive development, vegetative growth and leaf senescence, and suggest that GME regulates plant growth and controls male gametophyte development in different manners.

Toxicity and deficiency of copper in Elsholtzia splendens affect photosynthesis biophysics, pigments and metal accumulation.

Science.gov (United States)

Peng, Hongyun; Kroneck, Peter M H; Küpper, Hendrik

2013-06-18

Elsholtzia splendens is a copper-tolerant plant species growing on copper deposits in China. Spatially and spectrally resolved kinetics of in vivo absorbance and chlorophyll fluorescence in mesophyll of E. splendens were used to investigate the copper-induced stress from deficiency and toxicity as well as the acclimation to excess copper stress. The plants were cultivated in nutrient solutions containing either Fe(III)-EDTA or Fe(III)-EDDHA. Copper toxicity affected light-acclimated electron flow much stronger than nonphotochemical quenching (NPQ) or dark-acclimated photochemical efficiency of PSIIRC (Fv/Fm). It also changed spectrally resolved Chl fluorescence kinetics, in particular by strengthening the short-wavelength (<700 nm) part of NPQ altering light harvesting complex II (LHCII) aggregation. Copper toxicity reduced iron accumulation, decreased Chls and carotenoids in leaves. During acclimation to copper toxicity, leaf copper decreased but leaf iron increased, with photosynthetic activity and pigments recovering to normal levels. Copper tolerance in E. splendens was inducible; acclimation seems be related to homeostasis of copper and iron in E. splendens. Copper deficiency appeared at 10 mg copper per kg leaf DW, leading to reduced growth and decreased photosynthetic parameters (F0, Fv/Fm, ΦPSII). The importance of these results for evaluating responses of phytoremediation plants to stress in their environment is discussed.

A pomegranate (Punica granatum L.) WD40-repeat gene is a functional homologue of Arabidopsis TTG1 and is involved in the regulation of anthocyanin biosynthesis during pomegranate fruit development.

Science.gov (United States)

Ben-Simhon, Zohar; Judeinstein, Sylvie; Nadler-Hassar, Talia; Trainin, Taly; Bar-Ya'akov, Irit; Borochov-Neori, Hamutal; Holland, Doron

2011-11-01

Anthocyanins are the major pigments responsible for the pomegranate (Punica granatum L.) fruit skin color. The high variability in fruit external color in pomegranate cultivars reflects variations in anthocyanin composition. To identify genes involved in the regulation of anthocyanin biosynthesis pathway in the pomegranate fruit skin we have isolated, expressed and characterized the pomegranate homologue of the Arabidopsis thaliana TRANSPARENT TESTA GLABRA1 (TTG1), encoding a WD40-repeat protein. The TTG1 protein is a regulator of anthocyanins and proanthocyanidins (PAs) biosynthesis in Arabidopsis, and acts by the formation of a transcriptional regulatory complex with two other regulatory proteins: bHLH and MYB. Our results reveal that the pomegranate gene, designated PgWD40, recovered the anthocyanin, PAs, trichome and seed coat mucilage phenotype in Arabidopsis ttg1 mutant. PgWD40 expression and anthocyanin composition in the skin were analyzed during pomegranate fruit development, in two accessions that differ in skin color intensity and timing of appearance. The results indicate high positive correlation between the total cyanidin derivatives quantity (red pigments) and the expression level of PgWD40. Furthermore, strong correlation was found between the steady state levels of PgWD40 transcripts and the transcripts of pomegranate homologues of the structural genes PgDFR and PgLDOX. PgWD40, PgDFR and PgLDOX expression also correlated with the expression of pomegranate homologues of the regulatory genes PgAn1 (bHLH) and PgAn2 (MYB). On the basis of our results we propose that PgWD40 is involved in the regulation of anthocyanin biosynthesis during pomegranate fruit development and that expression of PgWD40, PgAn1 and PgAn2 in the pomegranate fruit skin is required to regulate the expression of downstream structural genes involved in the anthocyanin biosynthesis.

Pigmented xerodermoid - Report of three cases

Directory of Open Access Journals (Sweden)

Das Jayanta Kumar

2005-01-01

Full Text Available Pigmented xerodermoid, a rare genodermatosis, presents with clinical features and pathology similar to xeroderma pigmentosum, but at a later age. DNA repair replication is normal, but there is total depression of DNA synthesis after exposure to UV radiation. Two siblings in their teens and a man in his thirties with features of pigmented xerodermoid, e.g. photophobia, freckle-like lesions, keratoses, dryness of skin, and hypo- and hyper-pigmentation, are described. Although classically the onset of pigmented xerodermoid is said to be delayed till third to fourth decade of life, it seems the disease may appear earlier in the tropics. Early diagnosis and management could be life-saving.

Reference: 387 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available Michael F et al. 2006 Jul. Plant Physiol. 141(3):957-65. Karyogamy, or nuclear fusion, is essential for sex...ual reproduction. In angiosperms, karyogamy occurs three times: twice during double fertilization of the egg...e two polar nuclei fuse to form the diploid central cell nucleus. The molecular mechanisms controlling karyoga...etected during megagametogenesis. nfd1 is also affected in karyogamy during double fertilization. Using tran...odes the Arabidopsis RPL21M protein and is required for karyogamy during female g

Efficient Plastid Transformation in Arabidopsis.

Science.gov (United States)

Yu, Qiguo; Lutz, Kerry Ann; Maliga, Pal

2017-09-01

Plastid transformation is routine in tobacco ( Nicotiana tabacum ) but 100-fold less frequent in Arabidopsis ( Arabidopsis thaliana ), preventing its use in plastid biology. A recent study revealed that null mutations in ACC2 , encoding a plastid-targeted acetyl-coenzyme A carboxylase, cause hypersensitivity to spectinomycin. We hypothesized that plastid transformation efficiency should increase in the acc2 background, because when ACC2 is absent, fatty acid biosynthesis becomes dependent on translation of the plastid-encoded ACC β-carboxylase subunit. We bombarded ACC2 -defective Arabidopsis leaves with a vector carrying a selectable spectinomycin resistance ( aadA ) gene and gfp , encoding the green fluorescence protein GFP. Spectinomycin-resistant clones were identified as green cell clusters on a spectinomycin medium. Plastid transformation was confirmed by GFP accumulation from the second open reading frame of a polycistronic messenger RNA, which would not be translated in the cytoplasm. We obtained one to two plastid transformation events per bombarded sample in spectinomycin-hypersensitive Slavice and Columbia acc2 knockout backgrounds, an approximately 100-fold enhanced plastid transformation frequency. Slavice and Columbia are accessions in which plant regeneration is uncharacterized or difficult to obtain. A practical system for Arabidopsis plastid transformation will be obtained by creating an ACC2 null background in a regenerable Arabidopsis accession. The recognition that the duplicated ACCase in Arabidopsis is an impediment to plastid transformation provides a rational template to implement plastid transformation in related recalcitrant crops. © 2017 American Society of Plant Biologists. All Rights Reserved.

Carbachol-mediated pigment granule dispersion in retinal pigment epithelium requires Ca2+ and calcineurin

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García Dana M

2007-12-01

Full Text Available Abstract Background Inside bluegill (Lepomis macrochirus retinal pigment epithelial cells, pigment granules move in response to extracellular signals. During the process of aggregation, pigment motility is directed toward the cell nucleus; in dispersion, pigment is directed away from the nucleus and into long apical processes. A number of different chemicals have been found to initiate dispersion, and carbachol (an acetylcholine analog is one example. Previous research indicates that the carbachol-receptor interaction activates a Gq-mediated pathway which is commonly linked to Ca2+ mobilization. The purpose of the present study was to test for involvement of calcium and to probe calcium-dependent mediators to reveal their role in carbachol-mediated dispersion. Results Carbachol-induced pigment granule dispersion was blocked by the calcium chelator BAPTA. In contrast, the calcium channel antagonist verapamil, and incubation in Ca2+-free medium failed to block carbachol-induced dispersion. The calcineurin inhibitor cypermethrin blocked carbachol-induced dispersion; whereas, two protein kinase C inhibitors (staurosporine and bisindolylmaleimide II failed to block carbachol-induced dispersion, and the protein kinase C activator phorbol 12-myristate 13-acetate failed to elicit dispersion. Conclusion A rise in intracellular calcium is necessary for carbachol-induced dispersion; however, the Ca2+ requirement is not dependent on extracellular sources, implying that intracellular stores are sufficient to enable pigment granule dispersion to occur. Calcineurin is a likely Ca2+-dependent mediator involved in the signal cascade. Although the pathway leads to the generation of diacylglycerol and calcium (both required for the activation of certain PKC isoforms, our evidence does not support a significant role for PKC.

Key factors for UV curable pigment dispersions

International Nuclear Information System (INIS)

Magny, B.; Pezron, E.; Ciceron, P.H.; Askienazy, A.

1999-01-01

UV oligomers with good pigment dispersion are needed to allow good formulation flexibility and possibility to apply thinner films. Pigment dispersion mainly depends on three phenomena: the wetting of agglomerates, the breakage of agglomerates by mechanical stress and the stabilization of smaller agglomerates and primary particles against flocculation. It has been shown that oligomers with low viscosity and low surface tension induce a good pigment wetting. Examples of monomers and oligomers for good pigment dispersion are given

The Arabidopsis-related halophyte Thellungiella halophila: boron tolerance via boron complexation with metabolites?

Science.gov (United States)

Lamdan, Netta Li; Attia, Ziv; Moran, Nava; Moshelion, Menachem

2012-04-01

Tolerance to boron (B) is still not completely understood. We tested here the hypothesis that Thellungiella halophila, an Arabidopsis thaliana-related 'extremophile' plant, with abundance of B in its natural environment, is tolerant to B, and examined the potential mechanisms of this tolerance. With 1-10 mm B applied ([B](ext)) to Thellungiella and Arabidopsis grown in hydroponics, the steady-state accumulated B concentration ([B](int)) in the root was below [B](ext), and was similar in both, suggesting both extrude B actively. Whether grown in soil or hydroponically, the shoot [B](int) was higher in Arabidopsis than in Thellungiella, suggesting more effective net B exclusion by Thellungiella root. Arabidopsis exhibited toxicity symptoms including reduced shoot fresh weight (FW), but Thellungiella was not affected, even at similar levels of shoot-accumulated [B](int) (about 10 to 40 mm B in 'shoot water'), suggesting additional B tolerance mechanism in Thellungiella shoot. At [B](ext) = 5 mm, the summed shoot concentration of the potentially B-binding polyhydroxyl metabolites (malic acid, fructose, glucose, sucrose and citric acid) in Arabidopsis was below [B](int) , but in Thellungiella it was over twofold higher than [B](int) , and therefore likely to allow appreciable 1:2 boron-metabolite complexation in the shoot. This, we suggest, is an important component of Thellungiella B tolerance mechanism. © 2011 Blackwell Publishing Ltd.

The gecko visual pigments. The behavior of opsin.

Science.gov (United States)

Crescitelli, F

1979-05-01

The 521-pigment extracted out of the retina of the Tokay gecko has the typical stereospecificity of the vertebrate visual pigments. This is true for the pigment in the chloride-depleted, "blue-shifted" state as well as for the normal pigment with added chloride. While in the chloride-deficient state, pigment regeneration occurred with both 11-cis- and 9-cis-retinals and the regenerated photopigments were also in the blue-shifted, chloride-depleted state. As with the native pigment, these regenerated pigments were bathochromically shifted to their normal positions by the addition of chloride. Chloride-deficient opsin by itself also responded to chloride for the pigment regenerated with 11-cis-retinal from such chloride-treated opsin was in the normal 521-position. Regeneration was always rapid, reaching completion in less than 5 min, and was significantly faster than for cow rhodopsin regenerating under the same conditions. This rapid rate was found with or without chloride, with both 11-cis- and 9-cis-retinals and in the presence of the sulfhydryl poison, p-hydroxymercuribenzoate (PMB). Like the native chloride-deficient pigment, the regenerated chloride-depleted photopigments responded to PMB by a blue shift beyond the position of the chloride-deficient state. The addition of chloride to these "poisoned" regenerated pigments caused a bathochromic shift of such magnitude as to indicate a repair of both the PMB and chloride-deficient blue shift. In this discussion the possible implications of these results to phylogenetic considerations are considered as well as to some molecular properties of the 521-pigment.

Loss of ferulate 5-hydroxylase leads to Mediator-dependent inhibition of soluble phenylpropanoid biosynthesis in Arabidopsis

Energy Technology Data Exchange (ETDEWEB)

Anderson, Nickolas; Bonawitz, Nicholas D.; Nyffeler, Kayleigh E.; Chapple, Clint

2015-06-05

Phenylpropanoids are phenylalanine-derived specialized metabolites and include important structural components of plant cell walls, such as lignin and hydroxycinnamic acids, as well as ultraviolet and visible light-absorbing pigments, such as hydroxycinnamate esters (HCEs) and anthocyanins. Previous work has revealed a remarkable degree of plasticity in HCE biosynthesis, such that most Arabidopsis (Arabidopsis thaliana) mutants with blockages in the pathway simply redirect carbon flux to atypical HCEs. In contrast, the ferulic acid hydroxylase1 (fah1) mutant accumulates greatly reduced levels of HCEs, suggesting that phenylpropanoid biosynthesis may be repressed in response to the loss of FERULATE 5-HYDROXYLASE (F5H) activity. Here, we show that in fah1 mutant plants, the activity of HCE biosynthetic enzymes is not limiting for HCE accumulation, nor is phenylpropanoid flux diverted to the synthesis of cell wall components or flavonol glycosides. We further show that anthocyanin accumulation is also repressed in fah1 mutants and that this repression is specific to tissues in which F5H is normally expressed. Finally, we show that repression of both HCE and anthocyanin biosynthesis in fah1 mutants is dependent on the MED5a/5b subunits of the transcriptional coregulatory complex Mediator, which are similarly required for the repression of lignin biosynthesis and the stunted growth of the phenylpropanoid pathway mutant reduced epidermal fluorescence8. Taken together, these observations show that the synthesis of HCEs and anthocyanins is actively repressed in a MEDIATOR-dependent manner in Arabidopsis fah1 mutants and support an emerging model in which MED5a/5b act as central players in the homeostatic repression of phenylpropanoid metabolism.

The influences of Hygromycin B on growth of Arabidopsis thaliana ...

African Journals Online (AJOL)

In this article, growth and development of Arabidopsis thaliana seedling cotyledon and leaf were evidently affected by Hygromycin B. As compared to the control, cotyledon of seedling on Murashige and Skoog (MS) with Hygromycin B was very small and its leaf was not formed. Along with increase in culture time, cells in the ...

Non-aqueous pigmented inkjet inks

NARCIS (Netherlands)

DEROOVER, GEERT; Bernaerts, Katrien; HOOGMARTENS, IVAN

2009-01-01

A non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to Formula (I): wherein, T represents hydrogen or a polymerization terminating group; Z represents theA non-aqueous inkjet ink comprises a benzimidazolone pigment and a polymeric dispersant according to

Sinapic acid or its derivatives interfere with abscisic acid homeostasis during Arabidopsis thaliana seed germination.

Science.gov (United States)

Bi, Baodi; Tang, Jingliang; Han, Shuang; Guo, Jinggong; Miao, Yuchen

2017-06-06

Sinapic acid and its esters have broad functions in different stages of seed germination and plant development and are thought to play a role in protecting against ultraviolet irradiation. To better understand the interactions between sinapic acid esters and seed germination processes in response to various stresses, we analyzed the role of the plant hormone abscisic acid (ABA) in the regulation of sinapic acid esters involved in seed germination and early seedling growth. We found that exogenous sinapic acid promotes seed germination in a dose-dependent manner in Arabidopsis thaliana. High-performance liquid chromatography mass spectrometry analysis showed that exogenous sinapic acid increased the sinapoylcholine content of imbibed seeds. Furthermore, sinapic acid affected ABA catabolism, resulting in reduced ABA levels and increased levels of the ABA-glucose ester. Using mutants deficient in the synthesis of sinapate esters, we showed that the germination of mutant sinapoylglucose accumulator 2 (sng2) and bright trichomes 1 (brt1) seeds was more sensitive to ABA than the wild-type. Moreover, Arabidopsis mutants deficient in either abscisic acid deficient 2 (ABA2) or abscisic acid insensitive 3 (ABI3) displayed increased expression of the sinapoylglucose:choline sinapoyltransferase (SCT) and sinapoylcholine esterase (SCE) genes with sinapic acid treatment. This treatment also affected the accumulation of sinapoylcholine and free choline during seed germination. We demonstrated that sinapoylcholine, which constitutes the major phenolic component in seeds among various minor sinapate esters, affected ABA homeostasis during seed germination and early seedling growth in Arabidopsis. Our findings provide insights into the role of sinapic acid and its esters in regulating ABA-mediated inhibition of Arabidopsis seed germination in response to drought stress.

Microscopic Analysis of Pigments Extracted from Spalting Fungi

Directory of Open Access Journals (Sweden)

Sarath M. Vega Gutierrez

2017-03-01

Full Text Available Pigments that are currently available in the market usually come from synthetic sources, or, if natural, often need mordants to bind to the target substrate. Recent research on the fungal pigment extracts from Scytalidium cuboideum, Scytalidium ganodermophthorum, Chlorociboria aeruginosa, and Chlorociboria aeruginascens have been shown to successfully dye materials, like wood, bamboo, and textiles, however, there is no information about their binding mechanisms. Due to this, a microscopic study was performed to provide information to future manufacturers interested in these pigments. The results of this study show that S. ganodermophthorum and C. aeruginosa form an amorphous layer on substrates, while S. cuboideum forms crystal-like structures. The attachment and morphology indicate that there might be different chemical and physical interactions between the extracted pigments and the materials. This possibility can explain the high resistance of the pigments to UV light and color fastness that makes them competitive against synthetic pigments. These properties make these pigments a viable option for an industry that demands natural pigments with the properties of the synthetic ones.

Pigmentation changes in Siderastrea spp. during bleaching events in the costal reefs of northeastern Brazil

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Roberto Sassi

2015-03-01

Full Text Available We report here the occurrence of seasonal changes in the pigmentation of colonies of Siderastrea spp. during bleaching events on coastal reefs in northeastern Brazil. Bleached affected almost 50% of coral colonies analyzed in Cabo Branco reefs (Paraiba state in the summer of 2005. The same phenomenon was detected along various coastal reefs in northeastern Brazil during the summer of 2007 and 2008. These events were seasonal, and began with the emergence of pale colonies that became pale-pink and then purple during the rainy months. The patterns and intensity of colonies pigmentation changes varied with the studied sites. The decrease in zooxanthellae density and chlorophyll-a content was quantified in the colonies with their pigmentation pattern altered (bleaching. Microbiological analyses revealed higher densities of bacteria in pink colonies (bleached as compared to brown colonies (normal. Environmental disturbances may lead to the pigmentation changes in Siderastrea spp., but the immediate causes of this phenomenon are not clear and require further investigations.

PRODUCTION OF MONASCUS-LIKE AZAPHILONE PIGMENT

DEFF Research Database (Denmark)

2009-01-01

The present invention relates to the field of biotechnological production of polyketide based colorants from filamentous fungi, in particular a method for preparing a biomass comprising a Monascus-like pigment composition from a nontoxigenic and non-pathogenic fungal source. The present invention...... further relates to use of the Monascus-like pigment composition as a colouring agent for food items and/or non-food items, and a cosmetic composition comprising the Monascus-like pigment composition....

Pigmented xerodermoid - Report of three cases

OpenAIRE

Das Jayanta Kumar; Gangopadhyay Asok Kumar

2005-01-01

Pigmented xerodermoid, a rare genodermatosis, presents with clinical features and pathology similar to xeroderma pigmentosum, but at a later age. DNA repair replication is normal, but there is total depression of DNA synthesis after exposure to UV radiation. Two siblings in their teens and a man in his thirties with features of pigmented xerodermoid, e.g. photophobia, freckle-like lesions, keratoses, dryness of skin, and hypo- and hyper-pigmentation, are described. Although classically the on...

Production of Monascus-like azaphilone Pigment

DEFF Research Database (Denmark)

2009-01-01

The present invention relates to the field of biotechnological production of polyketide based colorants from filamentous fungi, in particular a method for preparing a biomass comprising a Monascus-like pigment composition from a nontoxigenic and non-pathogenic fungal source. The present invention...... further relates to use of the Monascus-like pigment composition as a colouring agent for food items and/or non-food items, and a cosmetic composition comprising the Monascus-like pigment composition....

Photosynthetic Pigments in Diatoms

OpenAIRE

Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

2015-01-01

Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvestin...

Pigmented villonodular synovitis of the hip in systemic lupus erythematosus: a case report

Directory of Open Access Journals (Sweden)

Anders Hans-Joachim

2011-09-01

Full Text Available Abstract Introduction Pigmented villonodular synovitis is a rare disease of unknown etiology mostly affecting the knee and foot. Until now an association with autoimmune diseases has not been reported. Case presentation The diagnosis of systemic lupus erythematosus was made in a 15-year-old Caucasian girl based on otherwise unexplained fatigue, arthralgia, tenosynovitis, leukopenia, low platelets and the presence of antinuclear and deoxyribonucleic antibodies. At the age of 20 a renal biopsy revealed lupus nephritis class IV and she went into complete remission with mycophenolate mofetil and steroids. She was kept on mycophenolate mofetil for maintenance therapy. At the age of 24 she experienced a flare-up of lupus nephritis with nephrotic syndrome and new onset of pain in her right hip. Magnetic resonance imaging, arthroscopy and subtotal synovectomy identified pigmented villonodular synovitis as the underlying diagnosis. Although her systemic lupus erythematosus went into remission with another course of steroids and higher doses of mycophenolate mofetil, the pigmented villonodular synovitis persisted and she had to undergo open synovectomy to control her symptoms. Conclusion Systemic lupus erythematosus is associated with many different musculoskeletal manifestations including synovitis and arthritis. Pigmented villonodular synovitis has not previously been reported in association with systemic lupus erythematosus, but as its etiology is still unknown, the present case raises the question about a causal relationship between systemic lupus erythematosus and pigmented villonodular synovitis.

A new quantitative evaluation method for age-related changes of individual pigmented spots in facial skin.

Science.gov (United States)

Kikuchi, K; Masuda, Y; Yamashita, T; Sato, K; Katagiri, C; Hirao, T; Mizokami, Y; Yaguchi, H

2016-08-01

Facial skin pigmentation is one of the most prominent visible features of skin aging and often affects perception of health and beauty. To date, facial pigmentation has been evaluated using various image analysis methods developed for the cosmetic and esthetic fields. However, existing methods cannot provide precise information on pigmented spots, such as variations in size, color shade, and distribution pattern. The purpose of this study is the development of image evaluation methods to analyze individual pigmented spots and acquire detailed information on their age-related changes. To characterize the individual pigmented spots within a cheek image, we established a simple object-counting algorithm. First, we captured cheek images using an original imaging system equipped with an illumination unit and a high-resolution digital camera. The acquired images were converted into melanin concentration images using compensation formulae. Next, the melanin images were converted into binary images. The binary images were then subjected to noise reduction. Finally, we calculated parameters such as the melanin concentration, quantity, and size of individual pigmented spots using a connected-components labeling algorithm, which assigns a unique label to each separate group of connected pixels. The cheek image analysis was evaluated on 643 female Japanese subjects. We confirmed that the proposed method was sufficiently sensitive to measure the melanin concentration, and the numbers and sizes of individual pigmented spots through manual evaluation of the cheek images. The image analysis results for the 643 Japanese women indicated clear relationships between age and the changes in the pigmented spots. We developed a new quantitative evaluation method for individual pigmented spots in facial skin. This method facilitates the analysis of the characteristics of various pigmented facial spots and is directly applicable to the fields of dermatology, pharmacology, and esthetic

RBP-Jκ-dependent Notch signaling enhances retinal pigment epithelial cell proliferation in transgenic mice.

Science.gov (United States)

Schouwey, K; Aydin, I T; Radtke, F; Beermann, F

2011-01-20

The Notch signaling pathway is an ubiquitous cell-cell interaction mechanism, which is essential in controlling processes like cell proliferation, cell fate decision, differentiation or stem cell maintenance. Recent data have shown that Notch signaling is RBP-Jκ-dependent in melanocytes, being required for survival of these pigment cells that are responsible for coloration of the skin and hairs in mammals. In addition, Notch is believed to function as an oncogene in melanoma, whereas it is a tumor suppressor in mouse epidermis. In this study, we addressed the implication of the Notch signaling in the development of another population of pigment cells forming the retinal pigment epithelium (RPE) in mammalian eyes. The constitutive activity of Notch in Tyrp1::NotchIC/° transgenic mice enhanced RPE cell proliferation, and the resulting RPE-derived pigmented tumor severely affected the overall eye structure. This RPE cell proliferation is dependent on the presence of the transcription factor RBP-Jκ, as it is rescued in mice lacking RBP-Jκ in the RPE. In conclusion, Notch signaling in the RPE uses the canonical pathway, which is dependent on the transcription factor RBP-Jκ. In addition, it is of importance for RPE development, and constitutive Notch activity leads to hyperproliferation and benign tumors of these pigment cells.

Mutations in CTNNA1 cause butterfly-shaped pigment dystrophy and perturbed retinal pigment epithelium integrity

NARCIS (Netherlands)

Saksens, N.T.; Krebs, M.P.; Schoenmaker, F.E.; Hicks, W.; Yu, M.; Shi, L.; Rowe, L.; Collin, G.B.; Charette, J.R.; Letteboer, S.J.; Neveling, K.; Moorsel, T.W. van; Abu-Ltaif, S.; Baere, E. De; Walraedt, S.; Banfi, S.; Simonelli, F.; Cremers, F.P.; Boon, C.J.; Roepman, R.; Leroy, B.P.; Peachey, N.S.; Hoyng, C.B.; Nishina, P.M.; Hollander, A.I. den

2016-01-01

Butterfly-shaped pigment dystrophy is an eye disease characterized by lesions in the macula that can resemble the wings of a butterfly. Here we report the identification of heterozygous missense mutations in the CTNNA1 gene (encoding alpha-catenin 1) in three families with butterfly-shaped pigment

Eggshell Biliverdin and Protoporphyrin Pigments in a Songbird: Are They Derived from Erythrocytes, Blood Plasma, or the Shell Gland?

Science.gov (United States)

Hargitai, Rita; Boross, Nóra; Hámori, Susanne; Neuberger, Eszter; Nyiri, Zoltán

Biliverdin and protoporphyrin pigments are deposited into the eggshell when the developing egg is in the shell gland. However, the site of synthesis of eggshell pigments is still uncertain, although it may influence the possible costs and potential functions of eggshell coloration in avian species. Eggshell pigments may be derived from red blood cells or be produced in other organs and then transferred to the shell gland, or they may be synthesized de novo in the shell gland. We studied in the canary (Serinus canaria) whether eggshell blue-green and brown pigmentations are associated with experimentally elevated anemia, female hematocrit level, immature erythrocyte percentage, and feces and plasma pigment levels during egg laying to find out the possible origin of eggshell pigments. We found no significant effects of hematocrit level or experimentally elevated anemia on intensity of eggshell blue-green and brown pigmentations; therefore, we consider it less likely that eggshell pigments are derived from erythrocytes. In addition, we found no significant associations between female feces biliverdin concentration during egg laying and intensity of eggshell blue-green pigmentation, suggesting that eggshell biliverdin may not originate from the spleen or liver. We found a negative association between plasma and feces protoporphyrin concentrations during egg laying and eggshell brown chroma. This result suggests that an increased production of protoporphyrin in the liver, which could have elevated plasma and feces protoporphyrin concentrations, could inhibit eggshell protoporphyrin pigmentation, probably through affecting enzymatic activities. We suggest that both pigments are produced de novo in the shell gland in the canary, but circulating pigment levels may influence shell gland pigment synthesis, thus connecting the physiological status of the female to eggshell coloration.

Seperation, identification and analysis of pigment (melanin ...

African Journals Online (AJOL)

Nine strains among 180 Streptomyces isolates produce a diffusible dark brown pigment on both peptone-yeast extract agar and synthetic tyrosine-agar. They also show the positive reaction to Ltyrosine or L-dopa substrates. The pigment has been referred to be as merely as dark brown watersoluble pigment, as melanoid or ...

Pigment retinopathy in warmblood horses with equine degenerative myeloencephalopathy and equine motor neuron disease.

Science.gov (United States)

Finno, Carrie J; Kaese, Heather J; Miller, Andrew D; Gianino, Giuliana; Divers, Thomas; Valberg, Stephanie J

2017-07-01

A pigment retinopathy has been reported in adult horses with equine motor neuron disease (EMND) arising from chronic α-tocopherol (α-TP) deficiency. A pigment retinopathy has not been identified in horses with neuroaxonal dystrophy/equine degenerative myeloencephalopathy (NAD/EDM) that affects genetically susceptible young horses with α-TP deficiency. The objective of this report is to describe, for the first time, a pigment retinopathy in a family of α-TP-deficient Warmbloods (WB) with clinically apparent NAD/EDM or EMND. Twenty-five WB horses from one farm underwent complete neurologic and ophthalmic examinations and serum α-TP concentrations were assessed. Two of the most severely ataxic horses were euthanized and postmortem examinations performed. Alpha-TP deficiency was widespread on this farm (22 of 25 horses). Eleven of 25 horses were clinically normal (age range 2-12 years), one had signs of EMND (6 years of age), 10 had signs of ataxia consistent with NAD/EDM (1-10 years), and two of these were postmortem confirmed concurrent NAD/EDM and EMND. A pigment retinopathy characterized by varying amounts of granular dark pigment in the tapetal retina was observed in four clinically apparent NAD/EDM horses (two postmortem confirmed concurrent NAD/EDM and EMND) and one horse with clinical signs of EMND. A pigment retinopathy can be present in young α-TP-deficient Warmblood horses with clinical signs of EMND as well as those with signs of NAD/EDM. © 2016 American College of Veterinary Ophthalmologists.

FRIENDLY regulates mitochondrial distribution, fusion, and quality control in Arabidopsis.

Science.gov (United States)

El Zawily, Amr M; Schwarzländer, Markus; Finkemeier, Iris; Johnston, Iain G; Benamar, Abdelilah; Cao, Yongguo; Gissot, Clémence; Meyer, Andreas J; Wilson, Ken; Datla, Raju; Macherel, David; Jones, Nick S; Logan, David C

2014-10-01

Mitochondria are defining components of most eukaryotes. However, higher plant mitochondria differ biochemically, morphologically, and dynamically from those in other eukaryotes. FRIENDLY, a member of the CLUSTERED MITOCHONDRIA superfamily, is conserved among eukaryotes and is required for correct distribution of mitochondria within the cell. We sought to understand how disruption of FRIENDLY function in Arabidopsis (Arabidopsis thaliana) leads to mitochondrial clustering and the effects of this aberrant chondriome on cell and whole-plant physiology. We present evidence for a role of FRIENDLY in mediating intermitochondrial association, which is a necessary prelude to mitochondrial fusion. We demonstrate that disruption of mitochondrial association, motility, and chondriome structure in friendly affects mitochondrial quality control and leads to mitochondrial stress, cell death, and strong growth phenotypes. © 2014 American Society of Plant Biologists. All Rights Reserved.

Pigmented Oral Lichen Planus: A Case Report

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Firstine Kelsi Hartanto

2017-09-01

Full Text Available Background: Lichen planus is a chronic muccocutaneous inflammatory disorder. Oral lichen planus (OLP has certain specific characteristics in its clinical presentation, but can also be presented in forms resembling other diseases. This may introduce difficulty in the diagnostic process. It has been reported that OLP affects between 0.1 to 4% individuals, predominantly women and people over 40 years old. Case Report: A 46-year-old woman complained of a non-healing ulcer present for 1.5 months. Intraorally, multiple white striae with prominent central areas of brownish hyperpigmentation were apparent on the right and left buccal mucosa, right and left buccal sulcus, and lateral and dorsum of the tongue. A biopsy was completed and the histopathology features confirmed the diagnosis of OLP. For the initial treatment, a topical corticosteroid was prescribed, followed by steroid mouthwash. Response to this treatment was positive. OLP has been frequently reported to affect women over the age of 40, with psychological stress as a primary predisposing factor. The clinical presentation is characteristic of Wickham’s striae with erosive areas. However, a biopsy and histopathological examination is mandatory to confirm the diagnosis. The clinical feature of pigmented OLP has been reported and confirmed by microscopic finding of band-like lymphocytic appearance which is the pathognomonic features of OLP, along with basal cell liquefaction degeneration, and melanin in continence at the lamina propria. Conclusion: Pigmented OLP is a variant of erosive OLP. Anamnesis, clinical presentation, and histopathological examination confirm diagnosis.

Proton beam modification of lead white pigments

International Nuclear Information System (INIS)

Beck, L.; Gutiérrez, P.C.; Miserque, F.; Thomé, L.

2013-01-01

Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3 MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings

Mechanical touch responses of Arabidopsis TCH1-3 mutant roots on inclined hard-agar surface

Science.gov (United States)

Zha, Guodong; Wang, Bochu; Liu, Junyu; Yan, Jie; Zhu, Liqing; Yang, Xingyan

2016-01-01

The gravity-induced mechanical touch stimulus can affect plant root architecture. Mechanical touch responses of plant roots are an important aspect of plant root growth and development. Previous studies have reported that Arabidopsis TCH1-3 genes are involved in mechano-related events, how-ever, the physiological functions of TCH1-3 genes in Arabidopsis root mechanoresponses remain unclear. In the present study, we applied an inclined hard agar plate method to produce mechanical touch stimulus, and provided evidence that altered mechanical environment could influence root growth. Furthermore, tch1-3 Arabidopsis mutants were investigated on inclined agar surfaces to explore the functions of TCH1-3 genes on Arabidopsis root mechanoresponses. The results showed that two tch2 mutants, cml24-2 and cml24-4, exhibited significantly reduced root length, biased skewing, and decreased density of lateral root. In addition, primary root length and density of lateral root of tch3 (cml12-2) was significantly decreased on inclined agar surfaces. This study indicates that the tch2 and tch3 mutants are hypersensitive to mechanical touch stimulus, and TCH2 (CML24-2 and CML24-4) and TCH3 (CML12-2) genes may participate in the mechanical touch response of Arabidopsis roots.

Arabidopsis FH1 Formin Affects Cotyledon Pavement Cell Shape by Modulating Cytoskeleton Dynamics.

Science.gov (United States)

Rosero, Amparo; Oulehlová, Denisa; Stillerová, Lenka; Schiebertová, Petra; Grunt, Michal; Žárský, Viktor; Cvrčková, Fatima

2016-03-01

Plant cell morphogenesis involves concerted rearrangements of microtubules and actin microfilaments. We previously reported that FH1, the main Arabidopsis thaliana housekeeping Class I membrane-anchored formin, contributes to actin dynamics and microtubule stability in rhizodermis cells. Here we examine the effects of mutations affecting FH1 (At3g25500) on cell morphogenesis and above-ground organ development in seedlings, as well as on cytoskeletal organization and dynamics, using a combination of confocal and variable angle epifluorescence microscopy with a pharmacological approach. Homozygous fh1 mutants exhibited cotyledon epinasty and had larger cotyledon pavement cells with more pronounced lobes than the wild type. The pavement cell shape alterations were enhanced by expression of the fluorescent microtubule marker GFP-microtubule-associated protein 4 (MAP4). Mutant cotyledon pavement cells exhibited reduced density and increased stability of microfilament bundles, as well as enhanced dynamics of microtubules. Analogous results were also obtained upon treatments with the formin inhibitor SMIFH2 (small molecule inhibitor of formin homology 2 domains). Pavement cell shape in wild-type (wt) and fh1 plants in some situations exhibited a differential response towards anti-cytoskeletal drugs, especially the microtubule disruptor oryzalin. Our observations indicate that FH1 participates in the control of microtubule dynamics, possibly via its effects on actin, subsequently influencing cell morphogenesis and macroscopic organ development. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Abscisic acid negatively regulates post-penetration resistance of Arabidopsis to the biotrophic powdery mildew fungus.

Science.gov (United States)

Xiao, Xiang; Cheng, Xi; Yin, Kangquan; Li, Huali; Qiu, Jin-Long

2017-08-01

Pytohormone abscisic acid (ABA) plays important roles in defense responses. Nonetheless, how ABA regulates plant resistance to biotrophic fungi remains largely unknown. Arabidopsis ABA-deficient mutants, aba2-1 and aba3-1, displayed enhanced resistance to the biotrophic powdery mildew fungus Golovinomyces cichoracearum. Moreover, exogenously administered ABA increased the susceptibility of Arabidopsis to G. cichoracearum. Arabidopsis ABA perception components mutants, abi1-1 and abi2-1, also displayed similar phenotypes to ABA-deficient mutants in resistance to G. cichoracearum. However, the resistance to G. cichoracearum is not changed in downstream ABA signaling transduction mutants, abi3-1, abi4-1, and abi5-1. Microscopic examination revealed that hyphal growth and conidiophore production of G. cichoracearum were compromised in the ABA deficient mutants, even though pre-penetration and penetration growth of the fungus were not affected. In addition, salicylic acid (SA) and MPK3 are found to be involved in ABA-regulated resistance to G. cichoracearum. Our work demonstrates that ABA negatively regulates post-penetration resistance of Arabidopsis to powdery mildew fungus G. cichoracearum, probably through antagonizing the function of SA.

DNA damage in isolated rat hepatocytes exposed to C.I. pigment orange 5 and C.I. pigment yellow 12 by the alkaline comet assay

DEFF Research Database (Denmark)

Møller, P; Wallin, Håkan; Grunnet, N

1998-01-01

The induction of DNA damage by commonly used printing ink pigments, C.I. pigment orange 5 (C.I. 12075) and C.I. pigment yellow 12 (C.I. 21090), was investigated in freshly isolated rat hepatocytes with the comet assay. C.I. pigment yellow 12 is a 3,3'-dichlorobenzidine-based diarylide pigment...

Three pectin methylesterase inhibitors protect cell wall integrity for arabidopsis immunity to Botrytis

DEFF Research Database (Denmark)

Lionetti, Vincenzo; Fabri, Eleonora; Caroli, Monica De

2017-01-01

to the control plants. A higher stimulation of the fungal oxalic acid biosynthetic pathway also can contribute to the higher susceptibility of pmei mutants. The lack of PMEI expression does not affect hemicellulose strengthening, callose deposition, and the synthesis of structural defense proteins, proposed...... is posttranscriptionally regulated by endogenous protein inhibitors (PMEIs). Here, AtPMEI10, AtPMEI11, and AtPMEI12 are identified as functional PMEIs induced in Arabidopsis (Arabidopsis thaliana) during B. cinerea infection. AtPMEI expression is strictly regulated by jasmonic acid and ethylene signaling, while only At...

Reference: 783 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available xpression of the Arabidopsis 10-kilodalton acyl-coenzyme A-binding protein ACBP6 en...phospholipid metabolism in Arabidopsis, including the possibility of ACBP6 in the cytosolic trafficking of phosphatidylcholine. Overe

Impact of Pigments on Self-Compacting Concrete

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Ernestas Ivanauskas

2011-04-01

Full Text Available We describe an impact of using iron oxide pigment on self-compacting concrete (SCC properties. We have experimented with adding portions of iron oxide pigment from 3 % to 6 % into cement paste. A few alternative pigments (chromic oxide and iron oxide hydroxide were used for performing the same experiments. The impact of these pigments on a normal cement paste is described in this paper. We demonstrate that iron oxide pigment reduces the need for water in a normal cement paste. However, adding the pigment also reduces the compressive strength of concrete up to 20 %. The concrete specimens were tested in various time spans, i.e. 1 day to 28 days, by keeping them in 20 ± 2 ºC water – normal consolidation regimen. Some of the specimens were processed in steam chamber, at 60 ºC in order to make the process of the cement hydration faster, as well as to estimate an impact of active SiO2 proportion in ash on SCC properties. We show that using iron oxide pigment for SCC mixture increases the slump-flow property of concrete mix up to 5 %. Experiments with solidified concrete have demonstrated that iron oxide diminishes water absorption up to 6 % and decreases open concrete porosity that makes concrete resistant against freezing. Article in Lithuanian

Allyl isothiocyanate affects the cell cycle of Arabidopsis thaliana

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Signe Elisabeth Åsberg

2015-05-01

Full Text Available Isothiocyanates (ITCs are degradation products of glucosinolates present in members of the Brassicaceae family acting as herbivore repellents and antimicrobial compounds. Recent results indicate that allyl ITC (AITC has a role in defense responses such as glutathione depletion, ROS generation and stomatal closure. In this study we show that exposure to non-lethal concentrations of AITC causes a shift in the cell cycle distribution of Arabidopsis thaliana leading to accumulation of cells in S-phases and a reduced number of cells in non-replicating phases. Furthermore, transcriptional analysis revealed an AITC-induced up-regulation of the gene encoding cyclin-dependent kinase A while several genes encoding mitotic proteins were down-regulated, suggesting an inhibition of mitotic processes. Interestingly, visualization of DNA synthesis indicated that exposure to AITC reduced the rate of DNA replication. Taken together, these results indicate that non-lethal concentrations of AITC induce cells of A. thaliana to enter the cell cycle and accumulate in S-phases, presumably as a part of a defensive response. Thus, this study suggests that AITC has several roles in plant defense and add evidence to the growing data supporting a multifunctional role of glucosinolates and their degradation products in plants.

The Arabidopsis histone chaperone FACT is required for stress-induced expression of anthocyanin biosynthetic genes.

Science.gov (United States)

Pfab, Alexander; Breindl, Matthias; Grasser, Klaus D

2018-03-01

The histone chaperone FACT is involved in the expression of genes encoding anthocyanin biosynthetic enzymes also upon induction by moderate high-light and therefore contributes to the stress-induced plant pigmentation. The histone chaperone FACT consists of the SSRP1 and SPT16 proteins and associates with transcribing RNAPII (RNAPII) along the transcribed region of genes. FACT can promote transcriptional elongation by destabilising nucleosomes in the path of RNA polymerase II, thereby facilitating efficient transcription of chromatin templates. Transcript profiling of Arabidopsis plants depleted in SSRP1 or SPT16 demonstrates that only a small subset of genes is differentially expressed relative to wild type. The majority of these genes is either up- or down-regulated in both the ssrp1 and spt16 plants. Among the down-regulated genes, those encoding enzymes of the biosynthetic pathway of the plant secondary metabolites termed anthocyanins (but not regulators of the pathway) are overrepresented. Upon exposure to moderate high-light stress several of these genes are up-regulated to a lesser extent in ssrp1/spt16 compared to wild type plants, and accordingly the mutant plants accumulate lower amounts of anthocyanin pigments. Moreover, the expression of SSRP1 and SPT16 is induced under these conditions. Therefore, our findings indicate that FACT is a novel factor required for the accumulation of anthocyanins in response to light-induction.

Microbial Production of Food Grade Pigments

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Laurent Dufossé

2006-01-01

Full Text Available The controversial topic of synthetic dyes in food has been discussed for many years. The scrutiny and negative assessment of synthetic food dyes by the modern consumer have raised a strong interest in natural colouring alternatives. Nature is rich in colours (minerals, plants, microalgae, etc., and pigment-producing microorganisms (fungi, yeasts, bacteria are quite common. Among the molecules produced by microorganisms are carotenoids, melanins, flavins, quinones, and more specifically monascins, violacein or indigo. The success of any pigment produced by fermentation depends upon its acceptability on the market, regulatory approval, and the size of the capital investment required to bring the product to market. A few years ago, some expressed doubts about the successful commercialization of fermentation-derived food grade pigments because of the high capital investment requirements for fermentation facilities and the extensive and lengthy toxicity studies required by regulatory agencies. Public perception of biotechnology-derived products also had to be taken into account. Nowadays some fermentative food grade pigments are on the market: Monascus pigments, astaxanthin from Xanthophyllomyces dendrorhous, Arpink Red from Penicillium oxalicum, riboflavin from Ashbya gossypii, b-carotene from Blakeslea trispora. The successful marketing of pigments derived from algae or extracted from plants, both as a food colour and a nutritional supplement, reflects the presence and importance of niche markets in which consumers are willing to pay a premium for »all natural ingredients«.

Studies on pigments of the myxomycete Physarum nudum. II. Separation and optical properties of the pigments from plasmodia cultured in darkness

Directory of Open Access Journals (Sweden)

L. Raczkowski

2015-01-01

Full Text Available The paper presents the data on Separation and some optical properties of the pigments obtained from the plasmodium of the myxomycete Physarum nudum grown in the dark. Pigment Separation was performed by means of thin-layer chromatography with celulose MN 300 as adsorbent and with the solvent: tert.-butylalcohol, H2O, 3N NH4OH at the ratio 5:2:1 In these conditions the chromatograms revealed 12 coloured bands from which pigments were eluted and their absorption spectra as well as the spectra of fluorescence emission were determined. The isolated pigments differ from one another by their physical properties (different Rf values, localization of absorption maxima, and behaviour in acid solution. Nevertheless, certain analogies perceptible between particular pigments per-mitted to distinguish 3 families of the studied pigments demonstrating similar properties.

Reference: 774 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available an essential gene, the disruption of which causes embryonic lethality. Plants carrying a hypomorphic smg7 mu...e progression from anaphase to telophase in the second meiotic division in Arabidopsis. Arabidopsis SMG7 is

Fish pigmentation and the melanocortin system.

Science.gov (United States)

Cal, Laura; Suarez-Bregua, Paula; Cerdá-Reverter, José Miguel; Braasch, Ingo; Rotllant, Josep

2017-09-01

The melanocortin system is a complex neuroendocrine signaling mechanism involved in numerous physiological processes in vertebrates, including pigmentation, steroidogenesis and metabolic control. This review focuses at one of its most fascinating function in fish, its regulatory role in the control of pigmentation, in which the melanocortin 1 receptor (Mc1r), its agonist α-melanocyte stimulating hormone (α-Msh), and the endogenous antagonist agouti signaling protein (Asip1) are the main players. Functional control of Mc1r, which is highly expressed in fish skin and whose activation stimulates melanin production and melanosome dispersion in fish melanophores, is considered a key mechanism for vertebrate pigment phenotypes. The α-Msh peptide, the most documented Mc1r agonist involved in pigmentation, is produced in the pituitary gland, activating melanin synthesis by binding to Mc1r in fish melanophores. Finally, Asip1 is the putative factor for establishing the evolutionarily conserved dorso-ventral pigment pattern found across vertebrates. However, we are just starting to understand how other melanocortin system components are acting in this complex regulatory network. Copyright © 2017 Elsevier Inc. All rights reserved.

Pigmented villonodular synovitis. A case report and review of the literature

International Nuclear Information System (INIS)

Restrepo, Juan P; Pilar M Maria

2010-01-01

Pigmented villonodular synovitis is a benign neoplasm with synovial proliferation and hemosiderin deposition. It occurs usually between 3th and 4th decades of life. Typically, it is monoarticular and can affect any joint but most commonly involves the large joints of the lower extremity. Treatment is based on the eradication of the tumor by surgery or radiotherapy.

Role of xanthophylls in light harvesting in green plants: a spectroscopic investigation of mutant LHCII and Lhcb pigment-protein complexes.

Science.gov (United States)

Fuciman, Marcel; Enriquez, Miriam M; Polívka, Tomáš; Dall'Osto, Luca; Bassi, Roberto; Frank, Harry A

2012-03-29

The spectroscopic properties and energy transfer dynamics of the protein-bound chlorophylls and xanthophylls in monomeric, major LHCII complexes, and minor Lhcb complexes from genetically altered Arabidopsis thaliana plants have been investigated using both steady-state and time-resolved absorption and fluorescence spectroscopic methods. The pigment-protein complexes that were studied contain Chl a, Chl b, and variable amounts of the xanthophylls, zeaxanthin (Z), violaxanthin (V), neoxanthin (N), and lutein (L). The complexes were derived from mutants of plants denoted npq1 (NVL), npq2lut2 (Z), aba4npq1lut2 (V), aba4npq1 (VL), npq1lut2 (NV), and npq2 (LZ). The data reveal specific singlet energy transfer routes and excited state spectra and dynamics that depend on the xanthophyll present in the complex.

Pigment dispersion syndrome masquerading as acute anterior uveitis.

Science.gov (United States)

Gonzalez-Gonzalez, Luis Alonso; Rodríguez-García, Alejandro; Foster, C Stephen

2011-06-01

Signs and symptoms of pigment dispersion may be confused with those of acute anterior uveitis. This case series is intended to aid the ophthalmologist in the clinical differentiation between these two disorders. The authors present a series of 6 patients with pigment dispersion who were initially diagnosed as having acute anterior uveitis and treated with anti-inflammatory medication, including corticosteroids. The patients were referred for a second opinion due to poor or no response to therapy and were found to have pigment dispersion instead of uveitis. Symptoms of pigment dispersion may consist of blurred vision, redness, ocular pain, and photophobia, all of which are also symptoms of acute anterior uveitis. These symptoms, plus the fact that pigment floating in the aqueous humor can be mistaken for inflammation, make diagnosis challenging. Moreover, the possible co-existence of true anterior uveitis and pigment dispersion makes the diagnosis and treatment more difficult.

Clinical characteristics of pigment dispersion syndrome in Chinese patients.

Science.gov (United States)

Qing, G; Wang, N; Tang, X; Zhang, S; Chen, H

2009-08-01

To report clinical findings and characteristics of pigment dispersion syndrome (PDS) in Chinese patients. PDS suspects with any one of the following signs: corneal endothelial pigmentation, iris transillumination defects (ITDs), pigment granule dusting on anterior iris surface, posterior iris bowing, trabecular meshwork (TM) pigmentation, and lenticular or zonular pigmentation were evaluated for PDS at the glaucoma specialty clinic at Beijing Tongren Eye Centre. Diagnosis of PDS required at least two of the following signs: Krukenberg spindle, moderate-to-heavy TM pigmentation (>or=Scheie II) and any degree of lenticular and/or zonular pigmentation. Eighteen patients (12 males and six females) were identified as having PDS during a 1-year period, with mean age of 35.5+/-7.0 years (range, 22-49). All but two eyes from two patients had myopia of -0.5 D or greater, with mean spherical equivalent power of -5.20+/-5.80 D (range, -24.75+/-0.5). The average IOP at initial diagnosis was 33.7+/-10.5 mm Hg (range, 16-56). Fifteen patients (83.3%) were found to have pigmentary glaucoma at their initial diagnosis. All patients showed homogenous increased TM pigmentation as well as lenticular and/or zonular pigmentation. 61.1% of patients (11 of 18) had Krukenberg spindle. None of the patients exhibited spoke-like midperipheral ITDs except for trace-isolated transillumination in both eyes of the two patients. The most common clinical findings in Chinese PDS patients include homogeneous TM pigmentation and pigment granule dusting on lens zonules and/or posterior peripheral lens surface. ITDs are uncommon in Chinese patients with PDS.

Regulation of Flavonoid Biosynthetic Genes in Germinating Arabidopsis Seedlings.

Science.gov (United States)

Kubasek, WL; Shirley, BW; McKillop, A; Goodman, HM; Briggs, W; Ausubel, FM

1992-01-01

Many higher plants, including Arabidopsis, transiently display purple anthocyanin pigments just after seed germination. We observed that steady state levels of mRNAs encoded by four flavonoid biosynthetic genes, PAL1 (encoding phenylalanine ammonia-lyase 1), CHS (encoding chalcone synthase), CHI (encoding chalcone isomerase), and DFR (encoding dihydroflavonol reductase), were temporally regulated, peaking in 3-day-old seedlings grown in continuous white light. Except for the case of PAL1 mRNA, mRNA levels for these flavonoid genes were very low in seedlings grown in darkness. Light induction studies using seedlings grown in darkness showed that PAL1 mRNA began to accumulate before CHS and CHI mRNAs, which, in turn, began to accumulate before DFR mRNA. This order of induction is the same as the order of the biosynthetic steps in flavonoid biosynthesis. Our results suggest that the flavonoid biosynthetic pathway is coordinately regulated by a developmental timing mechanism during germination. Blue light and UVB light induction experiments using red light- and dark-grown seedlings showed that the flavonoid biosynthetic genes are induced most effectively by UVB light and that blue light induction is mediated by a specific blue light receptor. PMID:12297632

Positive selection of a duplicated UV-sensitive visual pigment coincides with wing pigment evolution in Heliconius butterflies

Science.gov (United States)

Briscoe, Adriana D.; Bybee, Seth M.; Bernard, Gary D.; Yuan, Furong; Sison-Mangus, Marilou P.; Reed, Robert D.; Warren, Andrew D.; Llorente-Bousquets, Jorge; Chiao, Chuan-Chin

2010-01-01

The butterfly Heliconius erato can see from the UV to the red part of the light spectrum with color vision proven from 440 to 640 nm. Its eye is known to contain three visual pigments, rhodopsins, produced by an 11-cis-3-hydroxyretinal chromophore together with long wavelength (LWRh), blue (BRh) and UV (UVRh1) opsins. We now find that H. erato has a second UV opsin mRNA (UVRh2)—a previously undescribed duplication of this gene among Lepidoptera. To investigate its evolutionary origin, we screened eye cDNAs from 14 butterfly species in the subfamily Heliconiinae and found both copies only among Heliconius. Phylogeny-based tests of selection indicate positive selection of UVRh2 following duplication, and some of the positively selected sites correspond to vertebrate visual pigment spectral tuning residues. Epi-microspectrophotometry reveals two UV-absorbing rhodopsins in the H. erato eye with λmax = 355 nm and 398 nm. Along with the additional UV opsin, Heliconius have also evolved 3-hydroxy-DL-kynurenine (3-OHK)-based yellow wing pigments not found in close relatives. Visual models of how butterflies perceive wing color variation indicate this has resulted in an expansion of the number of distinguishable yellow colors on Heliconius wings. Functional diversification of the UV-sensitive visual pigments may help explain why the yellow wing pigments of Heliconius are so colorful in the UV range compared to the yellow pigments of close relatives lacking the UV opsin duplicate. PMID:20133601

Reference: 255 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available ases, AtIPK1 and AtIPK2beta, for the later steps of phytate synthesis in Arabidopsis thaliana. Coincident disruption...olyphosphate kinases in phosphate signaling biology. Generation of phytate-free seeds in Arabidopsis through disruption

Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa.

Directory of Open Access Journals (Sweden)

Dan Qian

Full Text Available Cyanate is toxic to all organisms. Cyanase converts cyanate to CO₂ and NH₃ in a bicarbonate-dependent reaction. The biophysical functions and biochemical characteristics of plant cyanases are poorly studied, although it has been investigated in a variety of proteobacteria, cyanobacteria and fungi. In this study, we characterised plant cyanases from Arabidopsis thaliana and Oryza sativa (AtCYN and OsCYN. Prokaryotic-expressed AtCYN and OsCYN both showed cyanase activity in vitro. Temperature had a similar influence on the activity of both cyanases, but pH had a differential impact on AtCYN and OsCYN activity. Homology modelling provided models of monomers of AtCYN and OsCYN, and a coimmunoprecipitation assay and gel filtration indicated that AtCYN and OsCYN formed homodecamers. The analysis of single-residue mutants of AtCYN indicated that the conserved catalytic residues also contributed to the stability of the homodecamer. KCNO treatment inhibited Arabidopsis germination and early seedling growth. Plants containing AtCYN or OsCYN exhibited resistance to KCNO stress, which demonstrated that one role of cyanases in plants is detoxification. Transcription level of AtCYN was higher in the flower than in other organs of Arabidopsis. AtCYN transcription was not significantly affected by KCNO treatment in Arabidopsis, but was induced by salt stress. This research broadens our knowledge on plant detoxification of cyanate via cyanase.

Surgical Management of Iatrogenic Pigment Dispersion Glaucoma.

Science.gov (United States)

Mierlo, Camille Van; Pinto, Luis Abegão; Stalmans, Ingeborg

2015-01-01

Iatrogenic pigment dispersion syndrome generally originates from a repetitive, mechanical trauma to the pigmented posterior epithelium of the iris. This trauma can arise after intraocular surgery, most commonly due to an abnormal contact between the intraocular lens (IOL) and the iris. Whether surgical removal of this primary insult can lead to a successful intraocular pressure (IOP) control remains unclear. Case-series. Patients with IOP elevation and clinical signs of pigment dispersion were screened for a diagnosis of iatrogenic IOL-related pigment dispersion. Three patients in which the IOL or the IOL-bag complex caused a pigment dispersion through a repetitive iris chafing were selected. In two cases, replacement of a sulcus-based single-piece IOL (patient 1) or a sub-luxated in-the-bag IOL (patient 2) by an anterior-chamber (AC) iris-fixed IOL led to a sustained decrease in IOP. In the third case, extensive iris atrophy and poor anatomical AC parameters for IOL implantation precluded further surgical intervention. IOL-exchange appears to be a useful tool in the management of iatrogenic pigment dispersion glaucoma due to inappropriate IOL implantation. This cause-oriented approach seems to be effective in controlling IOP, but should be offered only if safety criteria are met. How to cite this article: Van Mierlo C, Abegao Pinto L, Stalmans I. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma. J Curr Glaucoma Pract 2015;9(1):28-32.

Interaction between Vaccinium bracteatum Thunb. leaf pigment and rice proteins.

Science.gov (United States)

Wang, Li; Xu, Yuan; Zhou, Sumei; Qian, Haifeng; Zhang, Hui; Qi, Xiguang; Fan, Meihua

2016-03-01

In this study, we investigated the interaction of Vaccinium bracteatum Thunb. leaf (VBTL) pigment and rice proteins. In the presence of rice protein, VBTL pigment antioxidant activity and free polyphenol content decreased by 67.19% and 68.11%, respectively, and L(∗) of the protein-pigment complex decreased significantly over time. L(∗) values of albumin, globulin and glutelin during 60-min pigment exposure decreased by 55.00, 57.14, and 54.30%, respectively, indicating that these proteins had bound to the pigment. A significant difference in protein surface hydrophobicity was observed between rice proteins and pigment-protein complexes, indicating that hydrophobic interaction is a major binding mechanism between VBTL pigment and rice proteins. A significant difference in secondary structures between proteins and protein-pigment complexes was also uncovered, indicating that hydrogen bonding may be another mode of interaction between VBTL pigment and rice proteins. Our results indicate that VBTL pigment can stain rice proteins with hydrophobic and hydrogen interactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Skin Pigmentation Kinetics after Exposure to Ultraviolet A

DEFF Research Database (Denmark)

Ravnbak, M.H.; Philipsen, P.A.; Wiegell, S.R.

2009-01-01

Multiple exposures to ultraviolet radiation (UVR) are the norm in nature and phototherapy. However, studies of the kinetics of pigmentation following UVA exposure have included only fair-skinned persons. The aim of this study was to investigate steady-state pigmentation and fading in 12 Scandinav......Multiple exposures to ultraviolet radiation (UVR) are the norm in nature and phototherapy. However, studies of the kinetics of pigmentation following UVA exposure have included only fair-skinned persons. The aim of this study was to investigate steady-state pigmentation and fading in 12...... Scandinavians and 12 Indians/Pakistanis after 6 and 12 exposures on the back using broadband UVA and UVA1 with equal sub-minimal melanogenic doses (individually predetermined). Pigmentation was measured by skin reflectance at 555 and 660 urn. The UV dose to minimal pigmentation was higher in dark......-skinned persons after a single broadband UVA exposure, but independent of pigmentation/skin type after single and multiple UVA1 exposures. To elicit minimal melanogenic doses after 6 and 12 exposures, every dose is lowered by a factor of 2 and 3, respectively, but the cumulative dose increases three- and four...

Genome wide association mapping for the tolerance to the polyamine oxidase inhibitor guazatine in Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Kostadin Evgeniev eAtanasov

2016-04-01

Full Text Available Guazatine is a potent inhibitor of polyamine oxidase (PAO activity. In agriculture, guazatine is used as non-systemic contact fungicide efficient in the protection of cereals and citrus fruits against disease. The composition of guazatine is complex, mainly constituted by a mixture of synthetic guanidated polyamines (polyaminoguanidines. Here we have studied the effects from exposure to guazatine in the weed Arabidopsis thaliana. We report that micromolar concentrations of guazatine are sufficient to inhibit growth of Arabidopsis seedlings and induce chlorosis, whereas germination is barely affected. We observed the occurrence of quantitative variation in the response to guazatine between 107 randomly chosen Arabidopsis accessions. This enabled us to undertake genome-wide association (GWA mapping that identified a locus on chromosome one associated with guazatine tolerance. CHLOROPHYLLASE 1 (CLH1 within this locus was studied as candidate gene, together with its paralog (CLH2. The analysis of independent clh1-2, clh1-3, clh2-3, clh2-2 and double clh1-2 clh2-3 mutant alleles indicated that CLH1 and/or CLH2 loss-of-function or expression down-regulation promote guazatine tolerance in Arabidopsis. We report a natural mechanism by which Arabidopsis populations can overcome toxicity by the fungicide guazatine.

Pigment Production by the Edible Filamentous Fungus Neurospora Intermedia

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Rebecca Gmoser

2018-02-01

Full Text Available The production of pigments by edible filamentous fungi is gaining attention as a result of the increased interest in natural sources with added functionality in the food, feed, cosmetic, pharmaceutical and textile industries. The filamentous fungus Neurospora intermedia, used for production of the Indonesian food “oncom”, is one potential source of pigments. The objective of the study was to evaluate the fungus’ pigment production. The joint effect from different factors (carbon and nitrogen source, ZnCl2, MgCl2 and MnCl2 on pigment production by N. intermedia is reported for the first time. The scale-up to 4.5 L bubble column bioreactors was also performed to investigate the effect of pH and aeration. Pigment production of the fungus was successfully manipulated by varying several factors. The results showed that the formation of pigments was strongly influenced by light, carbon, pH, the co-factor Zn2+ and first- to fourth-order interactions between factors. The highest pigmentation (1.19 ± 0.08 mg carotenoids/g dry weight biomass was achieved in a bubble column reactor. This study provides important insights into pigmentation of this biotechnologically important fungus and lays a foundation for future utilizations of N. intermedia for pigment production.

Preparation, characterization and application of some anti- corrosive molybdate pigments

International Nuclear Information System (INIS)

Abd El-Ghaffar, M.A.; El-Sawy, S.M.; Ahmed, N.M.

2005-01-01

Some molybdate pigments of single and mixed metal ions, namely, zinc, calcium and zinc-calcium molybdates were prepared, characterized and evaluated according to international standard methods. The evaluated pigments were incorporated in some paint formulations. The physicomechanical, chemical and corrosion protective properties of the paint films were measured; this was done in comparison with a commercial imported molybdate pigment. It was found that, the prepared pigments under investigation are fine white crystalline powders of suitable pigment properties. They can be successfully used as environmentally acceptable anti corrosive pigments. They can replace satisfactorily the similar commercial imported pigment and possess adequate or superior properties against corrosion

ECA3, a Golgi-localized P_2A-type-ATPase, plays a crucial role in manganese nutrition in Arabidopsis

DEFF Research Database (Denmark)

Mills, Rebecca F.; Doherty, Melissa Louise; Lopez Marques, Rosa Laura

2008-01-01

and development, and transport processes play a key role in regulating their cellular levels. Arabidopsis (Arabidopsis thaliana) contains four P(2A)-type ATPase genes, AtECA1 to AtECA4, which are expressed in all major organs of Arabidopsis. To elucidate the physiological role of AtECA2 and AtECA3 in Arabidopsis...... not so striking because in this case all plants were severely affected. ECA3 partially restored the growth defect on high Mn of the yeast (Saccharomyces cerevisiae) pmr1 mutant, which is defective in a Golgi Ca/Mn pump (PMR1), and the yeast K616 mutant (Deltapmc1 Deltapmr1 Deltacnb1), defective in Golgi...

Pseudomonas aeruginosa induces pigment production and enhances virulence in a white phenotypic variant of Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Antonic V

2013-11-01

Full Text Available Vlado Antonic,1–3 Alexander Stojadinovic,3–5 Binxue Zhang,1–3 Mina J Izadjoo,1–3,5 Mohammad Alavi1–3 1Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA; 2Diagnostic and Translational Research Center, Gaithersburg, MD, USA; 3Combat Wound Initiative Program, Bethesda, MD, USA; 4Walter Reed National Military Medical Center, Bethesda, MD, USA; 5Uniformed Services University of the Health Sciences, Bethesda, MD, USA Abstract: Staphyloxanthin is a virulence factor which protects Staphylococcus aureus in stress conditions. We isolated two pigment variants of S. aureus and one strain of Pseudomonas aeruginosa from a single wound infection. S. aureus variants displayed white and yellow colony phenotypes. The sequence of the operons for staphyloxanthin synthesis indicated that coding and promoter regions were identical between the two pigment variants. Quorum sensing controls pigment synthesis in some bacteria. It is also shown that P. aeruginosa quorum-sensing molecules affect S. aureus transcription. We explored whether the co-infecting P. aeruginosa can affect pigment production in the white S. aureus variant. In co-culture experiments between the white variants and a selected number of Gram-positive and Gram-negative bacteria, only P. aeruginosa induced pigment production in the white variant. Gene expression analysis of the white variant did not indicate upregulation of the crtM and other genes known to be involved in pigment production (sigB, sarA, farnesyl pyrophosphate synthase gene [FPP-synthase], hfq. In contrast, transcription of the catalase gene was significantly upregulated after co-culture. P. aeruginosa-induced pigment synthesis and catalase upregulation correlated with increased resistance to polymyxin B, hydrogen peroxide, and the intracellular environment of macrophages. Our data indicate the presence of silent but functional staphyloxanthin synthesis machinery in a white phenotypic variant

Alternative Carrier Solvents for Pigments Extracted from Spalting Fungi

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Lauren Pittis

2018-05-01

Full Text Available The use of both naturally occurring and synthetic pigmented wood has been prevalent in woodcraft for centuries. Modern manifestations generally involve either woodworkers’ aniline dyes, or pigments derived from a special class of fungi known as spalting fungi. While fungal pigments are more renewable than anilines and pose less of an environmental risk, the carrier required for these pigments—dichloromethane (DCM—is both problematic for humans and tends to only deposit the pigments on the surface of wood instead of evenly within the material. Internal coloration of wood is key to adoption of a pigmenting system by woodworkers. To address this issue, five solvents that had moderate solubility with the pigments extracted from Chlorociboria aeruginosa and Scytalidium cuboideum were identified, in the hopes that a reduction in solubility would result in a greater amount of the pigment deposited inside the wood. Of the tested solvents, acetonitrile was found to produce the highest internal color in ash, Douglas-fir, madrone, mountain hemlock, Port-Orford cedar, Pacific silver fir, red alder and sugar maple. While these carrier solvents are not ideal for extracting the pigments from the fungi, acetonitrile in particular does appear to allow for more pigment to be deposited within wood. The use of acetonitrile over DCM offers new opportunities for possible industrial spalting applications, in which larger pieces of wood could be uniformly pigmented and sold to the end user in larger quantities than are currently available with spalted wood.

ASIP and TYR pigmentation variants associate with cutaneous melanoma and basal cell carcinoma.

NARCIS (Netherlands)

Gudbjartsson, D.F.; Sulem, P.; Stacey, S.N.; Goldstein, A.M.; Rafnar, T.; Sigurgeirsson, B.; Benediktsdottir, K.R.; Thorisdottir, K.; Ragnarsson, R.; Sveinsdottir, S.G.; Magnusson, V.; Lindblom, A.; Kostulas, K.; Botella-Estrada, R.; Soriano, V.; Juberias, P.; Grasa, M.; Saez, B.; Andres, R.; Scherer, D.; Rudnai, P.; Gurzau, E; Koppova, K.; Kiemeney, L.A.L.M.; Jakobsdottir, M.; Steinberg, S.; Helgason, A.; Gretarsdottir, S.; Tucker, M.A.; Mayordomo, J.I.; Nagore, E.; Kumar, R.; Hansson, J.; Olafsson, J.H.; Gulcher, J.R.; Kong, A.; Thorsteinsdottir, U.; Stefansson, K.

2008-01-01

Fair color increases risk of cutaneous melanoma (CM) and basal cell carcinoma (BCC). Recent genome-wide association studies have identified variants affecting hair, eye and skin pigmentation in Europeans. Here, we assess the effect of these variants on risk of CM and BCC in European populations

Genotype-environment interactions affect flower and fruit herbivory and plant chemistry of Arabidopsis thaliana in a transplant experiment

NARCIS (Netherlands)

Mosleh Arany, A.; de Jong, T.; Kim, H.K.; Van Dam, N.M.; Choi, Y.L.; van Mil, H.G.J.; Verpoorte, R.; van der Meijden, E.

2009-01-01

Large differences exist in flower and fruit herbivory between dune and inland populations of plants of Arabidopsis thaliana (Brassicaceae). Two specialist weevils Ceutorhynchus atomus and C. contractus (Curculionidae) and their larvae are responsible for this pattern in herbivory. We test, by means

EFFECTS OF FATLIQURING PROCESS ON LEATHERS COLOURED WITH IR REFLECTIVE DYES AND PIGMENTS

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MUTLU Mehmet Mete

2017-05-01

Full Text Available Black coloured materials and consumer goods are known to be heating up more, because they absorb sun radiation more than light colours. This heating is a problem for the users for black automotive or motorcycle leathers and also for dark shoes and boots which are exposed to sun heat. Human vision system can distinguish visible colours between the wavelengths of 390-700 nm. So reflecting the sun radiation in the infrared area of radiation spectrum higher than 700nm, is a solution for heating problem without affecting the visible colour. For this reason IR reflective dyes and pigments are designed. A leading Leather Chemical Company has developed an IR reflecting dyeing system for leather keeping the dark coloured leathers cooler under sun radiation. Additionally in theory, fat and water content of leather affects its heating properties. In this study, effect of natural, synthetic and waterproof fatliquoring systems on heating properties of leathers coloured with IR reflective dyes and pigments are investigated.

Non-conventional synthesis of ceramic pigments

International Nuclear Information System (INIS)

Dziubak, C.; Rutkowski, R.; Gebel, R.

2003-01-01

A short characterization of traditional methods of homogenization of components, used to produce ceramic pigments, was presented. Efficient and economic methods are searched to prepare raw material sets for ceramic pigments as alternative methods for the traditional way of wet mixing in ball mill or of dry mixing in the mixer of 'Z' type. The results of research of the use of sol-gel method to achieve these aims are presented. At the present stage of research, carried out on the yellow praseodymium and coral-pink iron-zirconium pigments show that traditional methods are better. (author)

Arabidopsis seedling flood-inoculation technique: a rapid and reliable assay for studying plant-bacterial interactions

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Uppalapati Srinivasa R

2011-10-01

Full Text Available Abstract Background The Arabidopsis thaliana-Pseudomonas syringae model pathosystem is one of the most widely used systems to understand the mechanisms of microbial pathogenesis and plant innate immunity. Several inoculation methods have been used to study plant-pathogen interactions in this model system. However, none of the methods reported to date are similar to those occurring in nature and amicable to large-scale mutant screens. Results In this study, we developed a rapid and reliable seedling flood-inoculation method based on young Arabidopsis seedlings grown on MS medium. This method has several advantages over conventional soil-grown plant inoculation assays, including a shorter growth and incubation period, ease of inoculation and handling, uniform infection and disease development, requires less growth chamber space and is suitable for high-throughput screens. In this study we demonstrated the efficacy of the Arabidopsis seedling assay to study 1 the virulence factors of P. syringae pv. tomato DC3000, including type III protein secretion system (TTSS and phytotoxin coronatine (COR; 2 the effector-triggered immunity; and 3 Arabidopsis mutants affected in salicylic acid (SA- and pathogen-associated molecular pattern (PAMPs-mediated pathways. Furthermore, we applied this technique to study nonhost resistance (NHR responses in Arabidopsis using nonhost pathogens, such as P. syringae pv. tabaci, pv. glycinea and pv. tomato T1, and confirmed the functional role of FLAGELLIN-SENSING 2 (FLS2 in NHR. Conclusions The Arabidopsis seedling flood-inoculation assay provides a rapid, efficient and economical method for studying Arabidopsis-Pseudomonas interactions with minimal growth chamber space and time. This assay could also provide an excellent system for investigating the virulence mechanisms of P. syringae. Using this method, we demonstrated that FLS2 plays a critical role in conferring NHR against nonhost pathovars of P. syringae, but not to

Encapsulating betalains from Opuntia ficus-indica fruits by ionic gelation: Pigment chemical stability during storage of beads.

Science.gov (United States)

Otálora, María Carolina; Carriazo, José Gregorio; Iturriaga, Laura; Osorio, Coralia; Nazareno, Mónica Azucena

2016-07-01

Betalain encapsulation was performed by ionic gelation as a stabilization strategy for these natural pigments. Betalains were extracted from purple cactus fruits and encapsulated in calcium-alginate and in combination of calcium alginate and bovine serum albumin. Beads were characterised by scanning electron microscopy and thermal analysis using differential scanning calorimetry and thermogravimetry. Moisture sorption isotherms were determined. Bead morphology was affected by matrix composition. Pigments storage stability was evaluated at different equilibrium relative humidity and temperatures. Pigment composition of beads was determined by HPLC-MS-MS and degradation products were also analysed after storage; betalamic acid being the major one. Both types of matrices protected the encapsulated pigments, being their storage stability better at low relative humidity than that of the non-encapsulated control material. Antiradical activities of beads were proportional to remaining betalain contents. At high relative humidity, there was no protection and low storage stability was observed in the samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

21 CFR 178.3725 - Pigment dispersants.

Science.gov (United States)

2010-04-01

... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pigment dispersants. 178.3725 Section 178.3725 Food...

Platelet-Rich Plasma Increases Pigmentation.

Science.gov (United States)

Uysal, Cagri A; Ertas, Nilgun Markal

2017-11-01

Platelet-rich plasma (PRP) is an autologous solution of plasma containing 4 to 7 times the baseline concentration of human platelets. Platelet-rich plasma has been widely popular in facial rejuvenation to attenuate wrinkles and has been practically used. The authors have been encountering various patients of increased hiperpigmentation following PRP applications that were performed to attenuate the postinflammatory hiperpigmentation especially after laser treatment. The authors have been using PRP for facial rejuvenation in selected patients and in 1 patient the authors have encountered increased pigmentation over the pigmented skin lesions that were present before the application. The authors recommend that the PRP might increase pigmentation especially in the face region and precautions might be taken before and after the application. Platelet-rich plasma should not be used for the treatment of post inflammatory hiperpigmentation.

Hyperspectral remote sensing of plant pigments.

Science.gov (United States)

Blackburn, George Alan

2007-01-01

The dynamics of pigment concentrations are diagnostic of a range of plant physiological properties and processes. This paper appraises the developing technologies and analytical methods for quantifying pigments non-destructively and repeatedly across a range of spatial scales using hyperspectral remote sensing. Progress in deriving predictive relationships between various characteristics and transforms of hyperspectral reflectance data are evaluated and the roles of leaf and canopy radiative transfer models are reviewed. Requirements are identified for more extensive intercomparisons of different approaches and for further work on the strategies for interpreting canopy scale data. The paper examines the prospects for extending research to the wider range of pigments in addition to chlorophyll, testing emerging methods of hyperspectral analysis and exploring the fusion of hyperspectral and LIDAR remote sensing. In spite of these opportunities for further development and the refinement of techniques, current evidence of an expanding range of applications in the ecophysiological, environmental, agricultural, and forestry sciences highlights the growing value of hyperspectral remote sensing of plant pigments.

[Primary pigmented breast adenocarcinoma in a male patient].

Science.gov (United States)

Dauendorffer, J-N; Pages, C; Abd Alsamad, I; Bagot, M; Fraitag, S

2013-01-01

Pigmented mammary tumours are rare. Herein, we report the third case of primary pigmented breast adenocarcinoma in a male patient with clinical mimicking of nodular melanoma of the nipple. A male patient presented with a pigmented nodule of the right nipple. Histological examination of the lesion showed dermal and subcutaneous adenocarcinomatous proliferation. The perilesional stroma contained melanin both inside and outside macrophages, leading us to conclude on primary pigmented breast adenocarcinoma clinically mimicking nodular melanoma of the nipple. Local production of melanin by neoplastic cells in the mammary carcinoma was postulated as the cause of hyperpigmentation of the tumour. Other possible causes are transfer of melanin from overlying melanocytes of the pigmented areolar epidermis to the underlying neoplastic cells, or melanin synthesis by intratumoral melanocytes migrating from the epidermis (which strikes us as the most convincing interpretation for the reported case). Breast adenocarcinoma is a rare tumour in men and may present clinically as a pigmented lesion of the nipple, resulting in the problem of differential diagnosis with primary or metastasised nodular melanoma. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Preparation of Mg(OH)_2 hybrid pigment by direct precipitation and graft onto cellulose fiber via surface-initiated atom transfer radical polymerization

International Nuclear Information System (INIS)

Wang, Xiao; Zhang, Yue; Lv, Lihua; Cui, Yongzhu; Wei, Chunyan; Pang, Guibing

2016-01-01

Graphical abstract: - Highlights: • Adsorbed anionic dye molecules are conducive to preferential growth of (0 0 1) plane of Mg(OH)_2 crystal for Mg(OH)_2 pigments. • Uniform coverage of nanosized Mg(OH)_2 pigments on fiber surface is achieved via surface-initiated ATRP. • About 4 wt% of Mg(OH)_2 pigment on fiber surface shortens nearly half of burning time of cellulose. - Abstract: Mg(OH)_2 flame retardant hybrid pigment is synthesized through simultaneous solution precipitation and adsorption of anionic dyes (C.I. Acid Red 6). The Mg(OH)_2 hybrid pigment bearing vinyl groups after surface silane modification is immobilized onto the surface of bromo end-functional cellulose fiber by atom transfer radical polymerization (ATRP). The morphology and structure of Mg(OH)_2 pigments and cellulose fibers grafted with modified pigments are characterized. The thermal properties, flammability and color fastness of cellulose fibers grafted with modified pigments are measured. The results reveal that anionic dye molecules are adsorbed onto Mg(OH)_2 crystals and affect the formation of lamella-like Mg(OH)_2 crystals. The cellulose fiber grafted with modified Mg(OH)_2 hybrid pigment absorbs about four times heat more than original cellulose fiber with about 4% immobilization ratio of pigment, which shortens nearly half of afterflame time and afterglow time.

To Investigate the Absorption, Dynamic Contact Angle and Printability Effects of Synthetic Zeolite Pigments in an Inkjet Receptive Coating

Science.gov (United States)

Jalindre, Swaraj Sunil

Ink absorption performance in inkjet receptive coatings containing synthetic zeolite pigments was studied. Coating pigment pore and particle size distribution are the key parameters that influence in modifying media surface properties, thus affecting the rate of ink penetration and drying time (Scholkopf, et al. 2004). The primary objective of this study was: (1) to investigate the synthetic zeolite pigment effects on inkjet ink absorption, dynamic contact angle and printability, and (2) to evaluate these novel synthetic zeolite pigments in replacing the fumed silica pigments in conventional inkjet receptive coatings. In this research study, single pigment coating formulations (in equal P:B ratio) were prepared using microporous synthetic zeolite pigments (5A, Organophilic and 13X) and polyvinyl alcohol (PVOH) binder. The laboratory-coated samples were characterized for absorption, air permeance, roughness, drying time, wettability and print fidelity. Based on the rheological data, it was found that the synthetic zeolite formulated coatings depicted a Newtonian flow behavior at low shear; while the industry accepted fumed silica based coatings displayed a characteristically high pseudoplastic flow behavior. Our coated samples generated using microporous synthetic zeolite pigments produced low absorption, reduced wettability and accelerated ink drying characteristics. These characteristics were caused due to the synthetic zeolite pigments, which resulted in relatively closed surface structure coated samples. The research suggested that no single selected synthetic zeolite coating performed better than the conventional fumed silica based coatings. Experimental data also showed that there was no apparent relationship between synthetic zeolite pigment pore sizes and inkjet ink absorption. For future research, above coated samples should be evaluated for pore size distribution using Mercury Porosimeter, which quantifies surface porosity of coated samples. This presented

Micro-pigmentation: implications for patients and professionals.

Science.gov (United States)

Collingridge, Kim; Calcluth, Julie

In the UK, reconstructive breast surgery is routinely offered to patients undergoing surgery for breast cancer. The results can be excellent, but without a nipple-areola complex the patient can feel incomplete. In response to patient need, an innovative nurse-led micro-pigmentation service has been developed in the authors' NHS trust, which provides women (and men) an opportunity to complete their reconstruction process. With the use of coloured pigments, micro-pigmentation creates a permanent image of a nipple-areola complex, which improves the aesthetic appearance of the surgically-created breast. As with the development of any new nurse-led innovation, the micro-pigmentation service has professional and client implications. Breast cancer can be devastating and may induce many psychological concerns, not least about body image and sexuality. This article addresses these issues, along with professional matters, such as autonomous practice, role expansion and the blurring of clinical boundaries. These factors are considered in relation to the nursing management of the micro-pigmentation service, where patient autonomy is encouraged to promote acceptance of self-image and closure on the breast cancer experience.

Membrane-localized ubiquitin ligase ATL15 functions in sugar-responsive growth regulation in Arabidopsis.

Science.gov (United States)

Aoyama, Shoki; Terada, Saki; Sanagi, Miho; Hasegawa, Yoko; Lu, Yu; Morita, Yoshie; Chiba, Yukako; Sato, Takeo; Yamaguchi, Junji

2017-09-09

Ubiquitin ligases play important roles in regulating various cellular processes by modulating the protein function of specific ubiquitination targets. The Arabidopsis Tóxicos en Levadura (ATL) family is a group of plant-specific RING-type ubiquitin ligases that localize to membranes via their N-terminal transmembrane-like domains. To date, 91 ATL isoforms have been identified in the Arabidopsis genome, with several ATLs reported to be involved in regulating plant responses to environmental stresses. However, the functions of most ATLs remain unknown. This study, involving transcriptome database analysis, identifies ATL15 as a sugar responsive ATL gene in Arabidopsis. ATL15 expression was rapidly down-regulated in the presence of sugar. The ATL15 protein showed ubiquitin ligase activity in vitro and localized to plasma membrane and endomembrane compartments. Further genetic analyses demonstrated that the atl15 knockout mutants are insensitive to high glucose concentrations, whereas ATL15 overexpression depresses plant growth. In addition, endogenous glucose and starch amounts were reciprocally affected in the atl15 knockout mutants and the ATL15 overexpressors. These results suggest that ATL15 protein plays a significant role as a membrane-localized ubiquitin ligase that regulates sugar-responsive plant growth in Arabidopsis. Copyright © 2017 Elsevier Inc. All rights reserved.

Pigment Production from Immobilized Monascus sp. Utilizing Polymeric Resin Adsorption

OpenAIRE

Evans, Patrick J.; Wang, Henry Y.

1984-01-01

Pigment production by the fungus Monascus sp. was studied to determine why Monascus sp. provides more pigment in solid culture than in submerged culture. Adding a sterilized nonionic polymeric adsorbent resin directly to the growing submerged culture did not enhance the pigment production, thus indicating that pigment extraction is probably not a factor. Monascus cells immobilized in hydrogel were studied and exhibited decreased pigment production as a result of immobilization. This result is...

Biomarker pigment signatures in Cochin back water system - A tropical estuary south west coast of India

Science.gov (United States)

Aneeshkumar, N.; Sujatha, C. H.

2012-03-01

Sedimentary biomarker pigments around Cochin estuary situated in the southwest coast of India were determined by HPLC. Fucoxanthin, an indicator of diatom was observed to be the most abundant carotenoid pigment in the estuary. Dinoflagellate derived carotenoid pigment peridinin was confined in the southern part of estuary and zeaxanthin pigment indicative of cyanobacteria were more found in sites influenced by anthropogenic activities. One compound having close similarity to fucoxanthin was also detected. Alloxanthin (cryptophyceae), chl b (green algae), canthaxanthin, neoxanthin, lutein and peridinin isomer were also detected by spectra and corresponding algal class were identified. The highest concentration of chl a (11.01 μg g-1) found near to the anthropogenic affected area while the lowest chl a (0.65 μg g-1) was recorded in industrial area. Degradation products of chl a, such as pheophorbide and pheophytin were observed and principal mode of mechanism of degradation were derived. Higher pheopigments content than chl a, reflects a density trapping of dead cells and early degradation of phytopigments from grazing activities.

Analysis of basidiomycete pigments in situ by Raman spectroscopy.

Science.gov (United States)

Tauber, James P; Matthäus, Christian; Lenz, Claudius; Hoffmeister, Dirk; Popp, Jürgen

2018-02-07

Basidiomycetes, that is, mushroom-type fungi, are known to produce pigments in response to environmental impacts. As antioxidants with a high level of unsaturation, these compounds can neutralize highly oxidative species. In the event of close contact with other microbes, the enzymatically controlled pigment production is triggered and pigment secretion is generated at the interaction zone. The identification and analysis of these pigments is important to understand the defense mechanism of fungi, which is essential to counteract an uncontrolled spread of harmful species. Usually, a detailed analysis of the pigments is time consuming as it depends on laborious sample preparation and isolation procedures. Furthermore, the applied protocols often influence the chemical integrity of the compound of interest. A possibility to noninvasively investigate the pigmentation is Raman microspectroscopy. The methodology has the potential to analyze the chemical composition of the sample spatially resolved at the interaction zone. After the acquisition of a representative spectroscopic library, the pigment production by basidiomycetes was monitored for during response to different fungi and bacteria. The presented results describe a very efficient noninvasive way of pigment analysis which can be applied with minimal sample preparation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis of chromium containing pigments from chromium galvanic sludges

International Nuclear Information System (INIS)

Andreola, F.; Barbieri, L.; Bondioli, F.; Cannio, M.; Ferrari, A.M.; Lancellotti, I.

2008-01-01

In this work the screening results of the scientific activity conducted on laboratory scale to valorise chromium(III) contained in the galvanic sludge as chromium precursor for ceramic pigments are reported. The valorisation of this waste as a secondary raw material (SRM) is obtained by achievement of thermal and chemical stable crystal structures able to color ceramic material. Two different pigments pink CaCr 0.04 Sn 0.97 SiO 5 and green Ca 3 Cr 2 (SiO 4 ) 3 were synthesized by solid-state reactions using dried Cr sludge as chromium oxide precursor. The obtained pigments were characterized by X-ray diffraction and SEM analysis. Furthermore the color developed in a suitable ceramic glaze was investigated in comparison with the color developed by the pigments prepared from pure Cr 2 O 3 . The characterization carried out corroborates the thermal and chemical stability of the synthesized pigments and, especially for the Cr-Sn pink pigment, the powders develop an intense color that is very similar to the color developed by the pigments obtained starting from pure Cr 2 O 3

Chemical characterisation of zircon-cadmium sulfoselenide ceramic pigments

International Nuclear Information System (INIS)

Gazulla Barreda, M. F.; Rodrigo Edo, M.; Blasco Roca, E.; Orduna Cordero, M.

2013-01-01

The present paper addresses the development of a methodology that allows the complete chemical characterisation of zircon cadmium sulfoselenide ceramic pigments including minor and major elements. To develop the methodology, five zircon-cadmium sulfoselenide pigments with different hues were selected, studying the different measurement process steps, from sample preparation to the optimisation of the measurement of the different components of the pigments by spectroscopic techniques (WD-XRF and elemental analysis by combustion and IR detection). The chemical characterisation method developed was validated with synthetic standards prepared from the mixture of certified reference materials and pure oxides because no certified referenced materials of this type of pigments were commercially available. The developed method can be used for a complete chemical characterization of zircon-cadmium sulfoselenide ceramic pigments with a very low uncertainty for all the elements analysed. (Author)

The Assessment of Natural Pigmentation in Archaeological Wool

DEFF Research Database (Denmark)

Scharff, Annemette Bruselius

2018-01-01

Naturally coloured wool contains pigment grains that mainly occur as ellipsoidal organelles (eumelanin) or spher¬ical grains (pheomelanin). Eumelanin is the most commonly occurring pigment, but naturally coloured wool fi¬bres contain both eumelanin and pheomelanin. In black and brown wool....... This can especially be the case if the pigments are degraded. When analysing the textiles from Lønne Hede (a Danish Iron Age inhumation grave), it was difficult to gain exact information about the natural pigmentation in some of the samples. To investigate this further, four samples of red-brown yarns from...... patterned fragments were selected for analyses. Earlier dyestuff analyses of the red-brown yarns gave no results, and it was therefore necessary to test the yarns for natural pigmentation. Three different methods were used for the analy¬ses. Transmitted light microscopy of whole mounts of the fibres...

A spontaneous dominant-negative mutation within a 35S::AtMYB90 transgene inhibits flower pigment production in tobacco.

Science.gov (United States)

Velten, Jeff; Cakir, Cahid; Cazzonelli, Christopher I

2010-03-29

In part due to the ease of visual detection of phenotypic changes, anthocyanin pigment production has long been the target of genetic and molecular research in plants. Specific members of the large family of plant myb transcription factors have been found to play critical roles in regulating expression of anthocyanin biosynthetic genes and these genes continue to serve as important tools in dissecting the molecular mechanisms of plant gene regulation. A spontaneous mutation within the coding region of an Arabidopsis 35S::AtMYB90 transgene converted the activator of plant-wide anthocyanin production to a dominant-negative allele (PG-1) that inhibits normal pigment production within tobacco petals. Sequence analysis identified a single base change that created a premature nonsense codon, truncating the encoded myb protein. The resulting mutant protein lacks 78 amino acids from the wild type C-terminus and was confirmed as the source of the white-flower phenotype. A putative tobacco homolog of AtMYB90 (NtAN2) was isolated and found to be expressed in flower petals but not leaves of all tobacco plants tested. Using transgenic tobacco constitutively expressing the NtAN2 gene confirmed the NtAN2 protein as the likely target of PG-1-based inhibition of tobacco pigment production. Messenger RNA and anthocyanin analysis of PG-1Sh transgenic lines (and PG-1Sh x purple 35S::NtAN2 seedlings) support a model in which the mutant myb transgene product acts as a competitive inhibitor of the native tobacco NtAN2 protein. This finding is important to researchers in the field of plant transcription factor analysis, representing a potential outcome for experiments analyzing in vivo protein function in test transgenic systems that over-express or mutate plant transcription factors.

N-Ethylmaleimide–Sensitive Factor b (nsfb) Is Required for Normal Pigmentation of the Zebrafish Retinal Pigment Epithelium

Science.gov (United States)

Hanovice, Nicholas J.; Daly, Christina M. S.; Gross, Jeffrey M.

2015-01-01

Purpose Despite the number of albinism-causing mutations identified in human patients and animal models, there remain a significant number of cases for which no mutation has been identified, suggesting that our understanding of melanogenesis is incomplete. Previously, we identified two oculocutaneous albinism mutations in zebrafish, au13 and au18. Here, we sought to identify the mutated loci and determine how the affected proteins contribute to normal pigmentation of the retinal pigment epithelium (RPE). Methods Complementation analyses revealed that au13 and au18 belonged to a single complementation group, suggesting that they affected the same locus. Whole-genome sequencing and single nucleotide polymorphism (SNP) analysis was performed to identify putative mutations, which were confirmed by cDNA sequencing and mRNA rescue. Transmission electron microscopy (TEM) and image quantification were used to identify the cellular basis of hypopigmentation. Results Whole-genome sequencing and SNP mapping identified a nonsense mutation in the N-ethylmaleimide–sensitive factor b (nsfb) gene in au18 mutants. Complementary DNA sequencing confirmed the presence of the mutation (C893T), which truncates the nsfb protein by roughly two-thirds (Y297X). No coding sequence mutations were identified in au13, but quantitative PCR revealed a significant decrease in nsfb expression, and nsfb mRNA injection rescued the hypopigmentation phenotype, suggesting a regulatory mutation. In situ hybridization revealed that nsfb is broadly expressed during embryonic development, including in the RPE. Transmission electron microscopy analyses indicated that average melanosome density and maturity were significantly decreased in nsfb mutants. Conclusions au18 and au13 contain mutations in nsfb, which encodes a protein that is required for the maturation of melanosomes in zebrafish RPE. PMID:26618645

Polycomb Group Proteins RING1A and RING1B Regulate the Vegetative Phase Transition in Arabidopsis

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Jian Li

2017-05-01

Full Text Available Polycomb group (PcG protein-mediated gene silencing is a major regulatory mechanism in higher eukaryotes that affects gene expression at the transcriptional level. Here, we report that two conserved homologous PcG proteins, RING1A and RING1B (RING1A/B, are required for global H2A monoubiquitination (H2Aub in Arabidopsis. The mutation of RING1A/B increased the expression of members of the SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL gene family and caused an early vegetative phase transition. The early vegetative phase transition observed in ring1a ring1b double mutant plants was dependent on an SPL family gene, and the H2Aub status of the chromatin at SPL locus was dependent on RING1A/B. Moreover, mutation in RING1A/B affected the miRNA156a-mediated vegetative phase transition, and RING1A/B and the AGO7-miR390-TAS3 pathway were found to additively regulate this transition in Arabidopsis. Together, our results demonstrate that RING1A/B regulates the vegetative phase transition in Arabidopsis through the repression of SPL family genes.

Arabidopsis: an adequate model for dicot root systems?

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Richard W Zobel

2016-02-01

Full Text Available The Arabidopsis root system is frequently considered to have only three classes of root: primary, lateral, and adventitious. Research with other plant species has suggested up to 8 different developmental/functional classes of root for a given plant root system. If Arabidopsis has only three classes of root, it may not be an adequate model for eudicot plant root systems. Recent research, however, can be interpreted to suggest that pre-flowering Arabidopsis does have at least five (5 of these classes of root. This then suggests that Arabidopsis root research can be considered an adequate model for eudicot plant root systems.

Neurotized congenital melanocytic nevus resembling a pigmented neurofibroma

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Nidhi Singh

2015-01-01

Full Text Available Neurotized congenital melanocytic nevus and pigmented neurofibroma (PNF are close mimics and pose a clinicopathological challenge. We present a case of pigmented hypertrichotic plaque over lumbosacral region and discuss the differential diagnosis and its clinical, histopathological and immunohistochemistry features which may aid in differentiation. We highlight the difficulties faced in differentiating neurotized congenital melanocytic nevus from pigmented neurofibroma.

Transgenic Arabidopsis Gene Expression System

Science.gov (United States)

Ferl, Robert; Paul, Anna-Lisa

2009-01-01

The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.

A molecular investigation of adsorption onto mineral pigments

Science.gov (United States)

Ninness, Brian J.

Pigment suspensions are important in several processes such as ceramics, paints, inks, and coatings. In the wet state, pigments are combined with a variety of chemical species such as polymers, surfactants, and polyelectrolytes which produce a complex colloidal system. The adsorption, desorption, and redistribution of these species at the pigment-aqueous solution interface can have an impact on the behavior in both the wet state or its final dried state. The goal of this work is to establish a molecular picture of the adsorption properties of these pigmented systems. A novel in situ infrared technique has been developed which allows the detection of adsorbed surface species on pigment particles in an aqueous environment. The technique involves the use of a polymeric binder to anchor the colloidal pigment particles to the surface of an internal reflection element (IRE). The binder only weakly perturbs about 25% of the reactive surface sites (hydroxyl groups) on silica. The reaction of succinic anhydride with an aminosilanized silica surface has been quantified using this technique. The adsorption dynamics of the cationic surfactant cetyltrimethylammonium bromide (C16TAB) at the TiO2-aqueous solution interface has been investigated using Fourier transform infrared-attenuated total reflection spectroscopy (FTIR-ATR) and electrokinetic analysis. At low bulk concentrations, C16TAB is shown to adsorb as isolated islands with a "defective" bilayer structure. Anionic probe molecules are shown to effectively "tune" the adsorbed surfactant microstructure. The results indicate that the structure of the adsorbed surfactant layer, and not the amount of adsorbed surfactant, dictates the subsequent adsorption behavior of the system. Atomic Layer Deposition is used to deposit a TiO2 layer onto the surfaces of silica and kaolin pigments. The process involves the cyclic reaction sequence of the vapors of TiCl4 and H2O. Three complete deposition cycles are needed before the surfaces

Pigment and terracotta analyses of Hellenistic figurines in Crete

International Nuclear Information System (INIS)

Maravelaki-Kalaitzaki, P.; Kallithrakas-Kontos, N.

2003-01-01

The results of the analyses performed on blue, black, brown, orange, white and purple pigments decorating Hellenistic figurines, excavated in a rock-cut tomb in the archaeological zone of Chania, Crete, Greece, are presented. Different spectroscopic techniques, such as Fourier transform infrared spectroscopy and energy dispersive X-ray fluorescence identified the compounds present in the chromatic layers. X-ray diffraction analysis gave complementary information and further support to the spectral assignments. Optical microscopy revealed the nature and sequence of the pigmented layer on the terracotta. Several precious pigments, such as Egyptian blue for the bluish areas, Tyrian purple for the purple ones, and the rare huntite for the white-pigmented areas were identified among the studied pigmented areas. The pigment analysis provides information on the technical aspects related to terracotta manufacture and preservation, and promotes historical indications on cultural and commercial changes among the Mediterranean civilisations

Sunscreening fungal pigments influence the vertical gradient of pendulous lichens in boreal forest canopies.

Science.gov (United States)

Färber, Leonie; Sølhaug, Knut Asbjorn; Esseen, Per-Anders; Bilger, Wolfgang; Gauslaa, Yngvar

2014-06-01

Pendulous lichens dominate canopies of boreal forests, with dark Bryoria species in the upper canopy vs. light Alectoria and Usnea species in lower canopy. These genera offer important ecosystem services such as winter forage for reindeer and caribou. The mechanism behind this niche separation is poorly understood. We tested the hypothesis that species-specific sunscreening fungal pigments protect underlying symbiotic algae differently against high light, and thus shape the vertical canopy gradient of epiphytes. Three pale species with the reflecting pigment usnic acid (Alectoria sarmentosa, Usnea dasypoga, U. longissima) and three with dark, absorbing melanins (Bryoria capillaris, B. fremontii, B. fuscescens) were compared. We subjected the lichens to desiccation stress with and without light, and assessed their performance with chlorophyll fluorescence. Desiccation alone only affected U. longissima. By contrast, light in combination with desiccation caused photoinhibitory damage in all species. Usnic lichens were significantly more susceptible to light during desiccation than melanic ones. Thus, melanin is a more efficient light-screening pigment than usnic acid. Thereby, the vertical gradient of pendulous lichens in forest canopies is consistent with a shift in type and functioning of sunscreening pigments, from high-light-tolerant Bryoria in the upper to susceptible Alectoria and Usnea in the lower canopy.

The gecko visual pigment: the anion hypsochromic effect.

Science.gov (United States)

Crescitelli, F; Karvaly, B

1991-01-01

The 521-pigment in the retina of the Tokay gecko (Gekko gekko) readily responds to particular physical and chemical changes in its environment. When solubilized in chloride deficient state the addition of Class I anions (Cl-, Br-) induces a bathochromic shift of the absorption spectrum. Class II anions (NO3-, IO3-, N3-, OCN-, SCN-, SeCN-, N(CN)2-), which exhibit ambidental properties, cause an hypsochromic shift. Class III anions (F-, I-, NO2-, CN-, AsO3-, SO2(4-), S2O2(3-) have no spectral effect on the 521-pigment. Cations appear to have no influence on the pigment absorption and Class I anions prevent or reverse the hypsochromic shift caused by Class II anions. It is suggested that the spectral displacements reflect specific changes in the opsin conformation, which alter the immediate (dipolar) environment of the retinal chromophore. The protein conformation seems to promote excited-state processes most in the native 521-pigment state and least in the presence of Class II anions. This in turn suggests that the photosensitivity of the 521-pigment is controlled by the excited rather than by the ground-state properties of the pigment.

Antimicrobial activity of Micrococcus luteus Cartenoid pigment

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Huda Z. Majeed

2017-11-01

Full Text Available Cartenoids are group of pigments, with enormous types different structurally and functionally, have colors range from red to yellow found in a wide variety of plants, fungi, algae and bacteria. The animals took from food because they cannot make it, on contrary, the plants and microbes produce them due to subjection to environment. The aim of the study is to isolate and characterize the cartenoid pigment from Micrococcus luteus. The pigment extraction was done by acetone, and then was characterized with UltraViolet-Visible spectroscopy (UV–Vis and Fourier Transform Infrared (FTIR spectroscopy. Then, it was tested for antibacterial activity against five different bacterial isolates and antifungal activity tests against six different fungal isolates by well diffusion method. The results found that, the extracted pigment having antibacterial activity and antifungal activity and having the ability to absorb UVA rays within the range of 300-500 nm. There was no significant difference in antimicrobial effect of pigment, even when the extraction and isolation were done by two culture mediums (Nutrient Broth and Luria Bertani Broth. There were considerable inhibition percentages of adhesion after subjection to Cartenoid pigment ranged between (5.71, 23.84 % for Klebsiella spp. and Pseudomonas aeruginosa respectively and all the 11 isolate changed from Biofilm producer to non-producer. The isolated compound can be used against different bacterial and fungal infections. So they had a great future in medicine, cosmetics and as a sun protecting agent.

Intraclutch variation in avian eggshell pigmentation: the anaemia hypothesis.

Science.gov (United States)

De Coster, Greet; De Neve, Liesbeth; Lens, Luc

2012-10-01

Many passerine species lay eggs that are speckled with dark protoporphyrin pigmentation. Because protoporphyrin is mainly derived from the blood, we here formulate and test a new hypothesis that links an increase in anaemia along the laying sequence to within-clutch variation in egg pigmentation. More intense pigmentation is expected if pigments accumulate during enhanced red blood cell production in response to anaemia. Reduced pigmentation is expected if pigments are derived from the degradation of red blood cells that circulate in smaller numbers due to blood loss. To test this hypothesis, we manipulated anaemia in great tit (Parus major) females by infesting the nests with hen fleas (Ceratophyllus gallinae) prior to egg laying. Polychromatophil (i.e., immature red blood cells) percentage, as a measure of blood cell production, was positively correlated with parasite load confirming that female great tits experienced stronger anaemia when infested with haematophagous parasites during egg laying. We found a positive relationship between spot darkness and laying order that weakened under high parasite load. This result suggests that anaemia in females due to blood-sucking parasites led to diminished protoporphyrin from disintegrated red blood cells and hence a decreased deposition of protoporphyrin. However, the overall increase in pigment darkness along the laying sequence suggests that pigments also accumulate by enhanced red blood cell production caused by anaemia due to egg production itself.

Multiscale Pigment Analysis of Medieval Illuminated Manuscripts

Science.gov (United States)

Sestak, Erica; Manukyan, Khachatur; Wiescher, Michael; Gura, David

2017-09-01

Three medieval illuminated manuscripts (codd. Lat. b. 1; Lat. b. 2; Lat. e. 4), housed at the University of Notre Dame's Hesburgh Library, vary in style, pigments, scribes, and regions, despite all three being Psalters used in the Late Middle Ages. XRF and Raman spectroscopy, which provided the elemental and molecular composition of the pigments, respectively, were used to analyze the pigments' compositions in an attempt to narrow further the manuscripts' possible origins. This experimental investigation emphasizes the importance of understanding the history of the manuscript through their pigments. Codd. Lat. b. 1 and Lat. b. 2 are Latinate German Psalters from the fifteenth century likely used in Katharinenkloster in Nuremberg. While there are visible differences in style within each Psalter, the variations in some of the pigment compositions, such as the inconstant presence of zinc, suggest different admixtures. Cod. Lat. e. 4 is a Latinate English Psalter from the fourteenth century, and it was written by two scribes and illuminated by two distinct painters. It is currently being tested to determine whether there are any correlations between the scribes and painters. These physical analyses will clarify the origins and provenances of the manuscripts.

Increasing Provasculature Complexity in the Arabidopsis Embryo May Increase Total Iron Content in Seeds: A Hypothesis

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Hannetz Roschzttardtz

2017-06-01

Full Text Available Anemia due to iron deficiency is a worldwide issue, affecting mainly children and women. Seed iron is a major source of this micronutrient for feeding, however, in most crops these levels are too low to meet daily needs. Thus, increasing iron allocation and its storage in seeds can represent an important step to enhance iron provision for humans and animals. Our knowledge on seed iron homeostasis is mainly based on studies performed in the model plant Arabidopsis thaliana, where iron accumulates in endodermis cells surrounding the embryo provasculature. It has been reported that cotyledon provasculature pattern complexity can be modified, thus we hypothesize that changes in the complexity of embryo vein patterns may affect total iron content in Arabidopsis seeds. This approach could be used as basis to develop strategies aimed to biofortify seeds.

Corrosion inhibition by lithium zinc phosphate pigment

International Nuclear Information System (INIS)

Alibakhshi, E.; Ghasemi, E.; Mahdavian, M.

2013-01-01

Highlights: •Synthesis of lithium zinc phosphate (LZP) by chemical co-precipitation method. •Corrosion inhibition activity of pigments compare with zinc phosphate (ZP). •LZP showed superior corrosion inhibition effect in EIS measurements. •Evaluation of adhesion strength and dispersion stability. -- Abstract: Lithium zinc phosphate (LZP) has been synthesized through a co-precipitation process and characterized by XRD and IR spectroscopy. The inhibitive performances of this pigment for corrosion of mild steel have been discussed in comparison with the zinc phosphate (ZP) in the pigment extract solution by means of EIS and in the epoxy coating by means of salt spray. The EIS and salt spray results revealed the superior corrosion inhibitive effect of LZP compared to ZP. Moreover, adhesion strength and dispersion stability of the pigmented epoxy coating showed the advantage of LZP compared to ZP

RNA-guided transcriptional activation via CRISPR/dCas9 mimics overexpression phenotypes in Arabidopsis.

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Jong-Jin Park

Full Text Available Clustered regularly interspaced short palindromic repeats (CRISPR and the CRISPR associated protein 9 (Cas9 system allows effective gene modification through RNA-guided DNA targeting. The Cas9 has undergone a series of functional alterations from the original active endonuclease to partially or completely deactivated Cas9. The catalytically deactivated Cas9 (dCas9 offers a platform to regulate transcriptional expression with the addition of activator or repressor domains. We redesigned a CRISPR/Cas9 activation system by adding the p65 transactivating subunit of NF-kappa B and a heat-shock factor 1 (HSF activation domain to dCas9 bound with the VP64 (tetramer of VP16 activation domain for application in plants. The redesigned CRISPR/Cas9 activation system was tested in Arabidopsis to increase endogenous transcriptional levels of production of anthocyanin pigment 1 (PAP1 and Arabidopsis thaliana vacuolar H+-pyrophosphatase (AVP1. The expression of PAP1 was increased two- to three-fold and the activated plants exhibited purple leaves similar to that of PAP1 overexpressors. The AVP1 gene expression was increased two- to five-fold in transgenic plants. In comparison to the wild type, AVP1 activated plants had increased leaf numbers, larger single-leaf areas and improved tolerance to drought stress. The AVP1 activated plants showed similar phenotypes to AVP1 overexpressors. Therefore, the redesigned CRISPR/Cas9 activation system containing modified p65-HSF provides a simple approach for producing activated plants by upregulating endogenous transcriptional levels.

Structural and Visible-Near Infrared Optical Properties of Cr-Doped TiO2 for Colored Cool Pigments

Science.gov (United States)

Yuan, Le; Weng, Xiaolong; Zhou, Ming; Zhang, Qingyong; Deng, Longjiang

2017-11-01

Chromium-doped TiO2 pigments were synthesized via a solid-state reaction method and studied with X-ray diffraction, SEM, XPS, and UV-VIS-NIR reflectance spectroscopy. The incorporation of Cr3+ accelerates the transition from the anatase phase to the rutile phase and compresses the crystal lattice. Moreover, the particle morphology, energy gap, and reflectance spectrum of Cr-doped TiO2 pigments is affected by the crystal structure and doping concentration. For the rutile samples, some of the Cr3+ ions are oxidized to Cr4+ after sintering at a high temperature, which leads to a strong near-infrared absorption band due to the 3A2 → 3 T1 electric dipole-allowed transitions of Cr4+. And the decrease of the band gap causes an obvious redshift of the optical absorption edges as the doping concentration increases. Thus, the VIS and near-infrared average reflectance of the rutile Ti1 - x Cr x O2 sample decrease by 60.2 and 58%, respectively, when the Cr content increases to x = 0.0375. Meanwhile, the color changes to black brown. However, for the anatase Ti1 - x Cr x O2 pigments, only the VIS reflection spectrum is inhibited by forming some characteristic visible light absorption peaks of Cr3+. The morphology, band gap, and NIR reflectance are not significantly affected. Finally, a Cr-doped anatase TiO2 pigment with a brownish-yellow color and 90% near-infrared reflectance can be obtained.

Differences in pigmentation between life cycle stages in Scrippsiella lachrymosa (dinophyceae).

Science.gov (United States)

Persson, Agneta; Smith, Barry C; Cyronak, Tyler; Cooper, Emily; DiTullio, Giacomo R

2016-02-01

Various life cycle stages of cyst-producing dinoflagellates often appear differently colored under the microscope; gametes appear paler while zygotes are darker in comparison to vegetative cells. To compare physiological and photochemical competency, the pigment composition of discrete life cycle stages was determined for the common resting cyst-producing dinoflagellate Scrippsiella lachrymosa. Vegetative cells had the highest cellular pigment content (25.2 ± 0.5 pg · cell(-1) ), whereas gamete pigment content was 22% lower. The pigment content of zygotes was 82% lower than vegetative cells, even though they appeared darker under the microscope. Zygotes of S. lachrymosa contained significantly higher cellular concentrations of β-carotene (0.65 ± 0.15 pg · cell(-1) ) than all other life stages. Photoprotective pigments and the de-epoxidation ratio of xanthophylls-cycle pigments in S. lachrymosa were significantly elevated in zygotes and cysts compared to other stages. This suggests a role for accessory pigments in combating intracellular oxidative stress during sexual reproduction or encystment. Resting cysts contained some pigments even though chloroplasts were not visible, suggesting that the brightly colored accumulation body contained photosynthetic pigments. The differences in pigmentation between life stages have implications for interpretation of pigment data from field samples when sampled during dinoflagellate blooms. © 2015 Phycological Society of America.

Fe K-edge XANES of Maya blue pigment

Science.gov (United States)

Río, M. Sánchez del; Sodo, A.; Eeckhout, S. G.; Neisius, T.; Martinetto, P.; Dooryhée, E.; Reyes-Valerio, C.

2005-08-01

The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the "Maya blue" pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si8(Mg2Al2)O20(OH)2(OH2)4.4H2O and an organic colourant (indigo: C16H10N2O2), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

Fe K-edge XANES of Maya blue pigment

International Nuclear Information System (INIS)

Rio, M. Sanchez del; Sodo, A.; Eeckhout, S.G.; Neisius, T.; Martinetto, P.; Dooryhee, E.; Reyes-Valerio, C.

2005-01-01

The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si 8 (Mg 2 Al 2 )O 20 (OH) 2 (OH 2 ) 4 .4H 2 O and an organic colourant (indigo: C 16 H 10 N 2 O 2 ), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue

Combined Laser Treatment in a Patient with Pigment Dispersion Secondary to a Large Iris Pigment Epithelial Cyst

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Özlem Yıldırım

2012-09-01

Full Text Available We reported a case of bilateral extensive iris pigment epithelial cysts masquerading as pigment dispersion. A-30-year-old male patient presented with a dull pain in both eyes and a decreased visual acuity OD. He underwent a complete ophthalmic examination. OD was injected and the cells were graded as +3 and pigmented a +2, in the OS. Intraocular pressures (IOP were measured as 42 (OD and 22 (OS mmHg. Gonioscopy revealed a confluent accumulation of dense pigment in both eyes. Visual fields, peripapillary retinal nerve fiber layer thickness (Spectral OCT/SLO OTI-OPKO Health. Inc, Miami, FL and optic nerve head tomography (HRT-II Heidelberg Engineering, Heidelberg, Germany results were within normal limits. On ultrasound biomicroscopy (UBM, bilateral extensive cysts were identified in the midzonal portion of the iris and in the ciliary body. An, antiglaucomatous treatment was started. Then, we decided to perform both Nd:YAG laser iridocystotomyc and selective laser trabeculoplasty. Fourteen months after the combined therapy, the cysts had not recurred, and still apposed and the IOPs were under control without medication.

Combined laser treatment in a patient with pigment dispersion secondary to a large iris pigment epithelial cyst.

Science.gov (United States)

Aykan, Umit; Yıldırım, Ozlem

2012-09-01

We reported a case of bilateral extensive iris pigment epithelial cysts masquerading as pigment dispersion. A-30-year-old male patient presented with a dull pain in both eyes and a decreased visual acuity OD. He underwent a complete ophthalmic examination. OD was injected and the cells were graded as +3 and pigmented a +2, in the OS. Intraocular pressures (IOP) were measured as 42 (OD) and 22 (OS) mmHg. Gonioscopy revealed a confluent accumulation of dense pigment in both eyes. Visual fields, peripapillary retinal nerve fiber layer thickness (Spectral OCT/SLO OTI-OPKO Health. Inc, Miami, FL) and optic nerve head tomography (HRT-II Heidelberg Engineering, Heidelberg, Germany) results were within normal limits. On ultrasound biomicroscopy (UBM), bilateral extensive cysts were identified in the midzonal portion of the iris and in the ciliary body. An, antiglaucomatous treatment was started. Then, we decided to perform both Nd:YAG laser iridocystotomyc and selective laser trabeculoplasty. Fourteen months after the combined therapy, the cysts had not recurred, and still apposed and the IOPs were under control without medication.

Structure and barrier properties of human embryonic stem cell-derived retinal pigment epithelial cells are affected by extracellular matrix protein coating.

Science.gov (United States)

Sorkio, Anni; Hongisto, Heidi; Kaarniranta, Kai; Uusitalo, Hannu; Juuti-Uusitalo, Kati; Skottman, Heli

2014-02-01

Extracellular matrix (ECM) interactions play a vital role in cell morphology, migration, proliferation, and differentiation of cells. We investigated the role of ECM proteins on the structure and function of human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells during their differentiation and maturation from hESCs into RPE cells in adherent differentiation cultures on several human ECM proteins found in native human Bruch's membrane, namely, collagen I, collagen IV, laminin, fibronectin, and vitronectin, as well as on commercial substrates of xeno-free CELLstart™ and Matrigel™. Cell pigmentation, expression of RPE-specific proteins, fine structure, as well as the production of basal lamina by hESC-RPE on different protein coatings were evaluated after 140 days of differentiation. The integrity of hESC-RPE epithelium and barrier properties on different coatings were investigated by measuring transepithelial resistance. All coatings supported the differentiation of hESC-RPE cells as demonstrated by early onset of cell pigmentation and further maturation to RPE monolayers after enrichment. Mature RPE phenotype was verified by RPE-specific gene and protein expression, correct epithelial polarization, and phagocytic activity. Significant differences were found in the degree of RPE cell pigmentation and tightness of epithelial barrier between different coatings. Further, the thickness of self-assembled basal lamina and secretion of the key ECM proteins found in the basement membrane of the native RPE varied between hESC-RPE cultured on compared protein coatings. In conclusion, this study shows that the cell culture substrate has a major effect on the structure and basal lamina production during the differentiation and maturation of hESC-RPE potentially influencing the success of cell integrations and survival after cell transplantation.

Single Molecule Spectroscopy on Photosynthetic Pigment-Protein Complexes

CERN Document Server

Jelezko, F; Schuler, S; Thews, E; Tietz, C; Wechsler, A; Wrachtrup, J

2001-01-01

Single molecule spectroscopy was applied to unravel the energy transfer pathway in photosynthetic pigment-protein complexes. Detailed analysis of excitation and fluorescence emission spectra has been made for peripheral plant antenna LHC II and Photosystem I from cyanobacterium Synechococcus elongatus. Optical transitions of individual pigments were resolved under nonselective excitation of antenna chlorophylls. High-resolution fluorescence spectroscopy of individual plant antenna LHC II indicates that at low temperatures, the excitation energy is localized on the red-most Chl a pool absorbing at 680 nm. More than one pigment molecule is responsible for the fluorescence emission of the LHC II trimer. The spectral lines of single Chl a molecules absorbing at 675 nm are broadened because of the Foerster energy transfer towards the red-most pigments. Low-temperature spectroscopy on single PS I trimers indicates that two subgroups of pigments, which are present in the red antenna pool, differ by the strength of t...

Mining the plant-herbivore interface with a leafmining Drosophila of Arabidopsis

Science.gov (United States)

Whiteman, Noah K.; Groen, Simon C.; Chevasco, Daniela; Bear, Ashley; Beckwith, Noor; Gregory, T. Ryan; Denoux, Carine; Mammarella, Nicole; Ausubel, Frederick M.; Pierce, Naomi E.

2010-01-01

Experimental infections of Arabidopsis thaliana (Arabidopsis) with genomically characterized plant pathogens such as Pseudomonas syringae have facilitated dissection of canonical eukaryotic defense pathways and parasite virulence factors. Plants are also attacked by herbivorous insects, and the development of an ecologically relevant genetic model herbivore that feeds on Arabidopsis will enable the parallel dissection of host defense and reciprocal resistance pathways such as those involved in xenobiotic metabolism. An ideal candidate is Scaptomyza flava, a drosophilid fly whose leafmining larvae are true herbivores that can be found in nature feeding on Arabidopsis and other crucifers. Here we describe the eukaryotic life cycle of S. flava on Arabidopsis, and use multiple approaches to characterize the response of Arabidopsis to S. flava attack. Oviposition choice tests and growth performance assays on different Arabidopsis ecotypes, defense-related mutants, and hormone and chitin-treated plants revealed significant differences in host preference and variation in larval performance across Arabidopsis accessions. The jasmonate (JA) and glucosinolate pathways in Arabidopsis are important in mediating quantitative resistance against S. flava, and priming with JA or chitin resulted in increased resistance. Expression of xenobiotic detoxification genes was reduced in S. flava larvae reared on Arabidopsis JA signaling mutants, and increased in plants pre-treated with chitin. These results and future research directions are discussed in the context of developing a genetic model system to analyze insect/plant interactions. PMID:21073583

Emerging greener extraction systems for fungal pigments isolation

OpenAIRE

Lebeau , Juliana; Venkatachalam , Mekala; Fouillaud , Mireille; Dufossé , Laurent; Caro , Yanis

2016-01-01

International audience; Filamentous fungi produce a mixture of various metabolites such as pigments, fatty acids, proteins and other cellular metabolites. Thus, extraction and isolation of the pigmented molecules of interest are necessary steps before proceeding to any further utilization of these metabolites for commercial applications. Pigments can be stored within the biomass, excreted in the fermentation broth or both, suggesting that extraction methods need to be developed accordingly to...

Neoplasia versus hyperplasia of the retinal pigment epithelium

DEFF Research Database (Denmark)

Heegaard, Steffen; Larsen, J.N.B.; Fledelius, Hans C.

2001-01-01

ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography......ophthalmology, retinal pigment epithelium, adenoma, tumor-like hyperplasia, histology, immunohistochemistry, tumor, neoplasm, ultrasonography...

Finnish wallpaper pigments in the 18th-19th century: Presence of KFe3(CrO4)2(OH)6 and odd pigment mixtures

Science.gov (United States)

Castro, Kepa; Knuutinen, Ulla; Vallejuelo, Silvia Fdez-Ortiz de; Irazola, Mireia; Madariaga, Juan Manuel

2013-04-01

Several Finish wallpapers from the 18th and 19th century were analysed by using Raman spectroscopy assisted with EDXRF instrumentation, in an attempt of determine the pigments used in their manufacture process as well as of trying to date some of the samples through pigment composition. All pigments present in samples were determined and surprisingly the unusual and strange iron (III) chromate yellow pigment was found. Besides, unusual mixtures were found to obtain fashionable colours, especially in blue and green areas, where more than one blue pigments were mixed with green and yellow pigments. Blue verditer, ultramarine blue, Prussian blue, chrome yellow, calcite, lead white, red and yellow iron oxide, gypsum and carbon black were identified. The presence of the risky and poisonous emerald green must be highlighted. The results were compared with those found in other wallpapers from Spain and France.

Novel Genes Affecting the Interaction between the Cabbage Whitefly and Arabidopsis Uncovered by Genome-Wide Association Mapping.

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Colette Broekgaarden

Full Text Available Plants have evolved a variety of ways to defend themselves against biotic attackers. This has resulted in the presence of substantial variation in defense mechanisms among plants, even within a species. Genome-wide association (GWA mapping is a useful tool to study the genetic architecture of traits, but has so far only had limited exploitation in studies of plant defense. Here, we study the genetic architecture of defense against the phloem-feeding insect cabbage whitefly (Aleyrodes proletella in Arabidopsis thaliana. We determined whitefly performance, i.e. the survival and reproduction of whitefly females, on 360 worldwide selected natural accessions and subsequently performed GWA mapping using 214,051 SNPs. Substantial variation for whitefly adult survival and oviposition rate (number of eggs laid per female per day was observed between the accessions. We identified 39 candidate SNPs for either whitefly adult survival or oviposition rate, all with relatively small effects, underpinning the complex architecture of defense traits. Among the corresponding candidate genes, i.e. genes in linkage disequilibrium (LD with candidate SNPs, none have previously been identified as a gene playing a role in the interaction between plants and phloem-feeding insects. Whitefly performance on knock-out mutants of a number of candidate genes was significantly affected, validating the potential of GWA mapping for novel gene discovery in plant-insect interactions. Our results show that GWA analysis is a very useful tool to gain insight into the genetic architecture of plant defense against herbivorous insects, i.e. we identified and validated several genes affecting whitefly performance that have not previously been related to plant defense against herbivorous insects.

Fe K-edge XANES of Maya blue pigment

Energy Technology Data Exchange (ETDEWEB)

Rio, M. Sanchez del [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France)]. E-mail: srio@esrf.fr; Sodo, A. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Eeckhout, S.G. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Neisius, T. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Martinetto, P. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico)

2005-08-15

The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si{sub 8}(Mg{sub 2}Al{sub 2})O{sub 20}(OH){sub 2}(OH{sub 2}){sub 4}.4H{sub 2}O and an organic colourant (indigo: C{sub 16}H{sub 10}N{sub 2}O{sub 2}), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

Using "Arabidopsis" Genetic Sequences to Teach Bioinformatics

Science.gov (United States)

Zhang, Xiaorong

2009-01-01

This article describes a new approach to teaching bioinformatics using "Arabidopsis" genetic sequences. Several open-ended and inquiry-based laboratory exercises have been designed to help students grasp key concepts and gain practical skills in bioinformatics, using "Arabidopsis" leucine-rich repeat receptor-like kinase (LRR…

Nanoscale Coloristic Pigments: Upper Limits on Releases from Pigmented Plastic during Environmental Aging, In Food Contact, and by Leaching.

Science.gov (United States)

Neubauer, Nicole; Scifo, Lorette; Navratilova, Jana; Gondikas, Andreas; Mackevica, Aiga; Borschneck, Daniel; Chaurand, Perrine; Vidal, Vladimir; Rose, Jerome; von der Kammer, Frank; Wohlleben, Wendel

2017-10-17

The life cycle of nanoscale pigments in plastics may cause environmental or human exposure by various release scenarios. We investigated spontaneous and induced release with mechanical stress during/after simulated sunlight and rain degradation of polyethylene (PE) with organic and inorganic pigments. Additionally, primary leaching in food contact and secondary leaching from nanocomposite fragments with an increased surface into environmental media was examined. Standardized protocols/methods for release sampling, detection, and characterization of release rate and form were applied: Transformation of the bulk material was analyzed by Scanning Electron Microscopy (SEM), X-ray-tomography and Fourier-Transform Infrared spectroscopy (FTIR); releases were quantified by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), single-particle-ICP-MS (sp-ICP-MS), Transmission Electron Microscopy (TEM), Analytical Ultracentrifugation (AUC), and UV/Vis spectroscopy. In all scenarios, the detectable particulate releases were attributed primarily to contaminations from handling and machining of the plastics, and were not identified with the pigments, although the contamination of 4 mg/kg (Fe) was dwarfed by the intentional content of 5800 mg/kg (Fe as Fe 2 O 3 pigment). We observed modulations (which were at least partially preventable by UV stabilizers) when comparing as-produced and aged nanocomposites, but no significant increase of releases. Release of pigments was negligible within the experimental error for all investigated scenarios, with upper limits of 10 mg/m 2 or 1600 particles/mL. This is the first holistic confirmation that pigment nanomaterials remain strongly contained in a plastic that has low diffusion and high persistence such as the polyolefin High Density Polyethylene (HDPE).

Pigment Production on L-Tryptophan Medium by Cryptococcus gattii and Cryptococcus neoformans

Science.gov (United States)

Chaskes, Stuart; Cammer, Michael; Nieves, Edward; Casadevall, Arturo

2014-01-01

In recent years strains previously grouped within Cryptococcus neoformans have been divided into two species C. neoformans and C. gattii, with Cryptococcus neoformans comprising serotypes A, D, and AD and C. gattii comprising serotypes B and C. Cryptococcus neoformans have also been subdivided into two varieties C. neoformans var. grubii, serotype A, and C. neoformans var. neoformans, serotype D. We analyzed the growth and pigment production characteristics of 139 strains of Cryptococcus spp. in L-tryptophan containing media. Nearly all strains of Cryptococcus, including each variety and serotype tested produced a pink water-soluble pigment (molecular weight of 535.2 Da) from L-tryptophan. Consequently, the partial separation of the species was based on whether the pink pigment was secreted into the medium (extracellular) or retained as an intracellular pigment. On L-tryptophan medium C. neoformans var. grubii and serotype AD produced a pink extracellular pigment. In contrast, for C. gattii, the pink pigment was localized intracellularly and masked by heavy production of brown pigments. Pigment production by C. neoformans var. neoformans was variable with some strains producing the pink extracellular pigment and others retained the pink pigment intracellularly. The pink intracellular pigment produced by strains of C. neoformans var. neoformans was masked by production of brown pigments. Cryptococcus laccase mutants failed to produce pigments from L-tryptophan. This is the first report that the enzyme laccase is involved in tryptophan metabolism. Prior to this report Cryptococcus laccase produced melanin or melanin like-pigments from heterocyclic compounds that contained ortho or para diphenols, diaminobenzenes and aminophenol compounds. The pigments produced from L-tryptophan were not melanin. PMID:24736553

Pigment production on L-tryptophan medium by Cryptococcus gattii and Cryptococcus neoformans.

Science.gov (United States)

Chaskes, Stuart; Cammer, Michael; Nieves, Edward; Casadevall, Arturo

2014-01-01

In recent years strains previously grouped within Cryptococcus neoformans have been divided into two species C. neoformans and C. gattii, with Cryptococcus neoformans comprising serotypes A, D, and AD and C. gattii comprising serotypes B and C. Cryptococcus neoformans have also been subdivided into two varieties C. neoformans var. grubii, serotype A, and C. neoformans var. neoformans, serotype D. We analyzed the growth and pigment production characteristics of 139 strains of Cryptococcus spp. in L-tryptophan containing media. Nearly all strains of Cryptococcus, including each variety and serotype tested produced a pink water-soluble pigment (molecular weight of 535.2 Da) from L-tryptophan. Consequently, the partial separation of the species was based on whether the pink pigment was secreted into the medium (extracellular) or retained as an intracellular pigment. On L-tryptophan medium C. neoformans var. grubii and serotype AD produced a pink extracellular pigment. In contrast, for C. gattii, the pink pigment was localized intracellularly and masked by heavy production of brown pigments. Pigment production by C. neoformans var. neoformans was variable with some strains producing the pink extracellular pigment and others retained the pink pigment intracellularly. The pink intracellular pigment produced by strains of C. neoformans var. neoformans was masked by production of brown pigments. Cryptococcus laccase mutants failed to produce pigments from L-tryptophan. This is the first report that the enzyme laccase is involved in tryptophan metabolism. Prior to this report Cryptococcus laccase produced melanin or melanin like-pigments from heterocyclic compounds that contained ortho or para diphenols, diaminobenzenes and aminophenol compounds. The pigments produced from L-tryptophan were not melanin.

Pigment production on L-tryptophan medium by Cryptococcus gattii and Cryptococcus neoformans.

Directory of Open Access Journals (Sweden)

Stuart Chaskes

Full Text Available In recent years strains previously grouped within Cryptococcus neoformans have been divided into two species C. neoformans and C. gattii, with Cryptococcus neoformans comprising serotypes A, D, and AD and C. gattii comprising serotypes B and C. Cryptococcus neoformans have also been subdivided into two varieties C. neoformans var. grubii, serotype A, and C. neoformans var. neoformans, serotype D. We analyzed the growth and pigment production characteristics of 139 strains of Cryptococcus spp. in L-tryptophan containing media. Nearly all strains of Cryptococcus, including each variety and serotype tested produced a pink water-soluble pigment (molecular weight of 535.2 Da from L-tryptophan. Consequently, the partial separation of the species was based on whether the pink pigment was secreted into the medium (extracellular or retained as an intracellular pigment. On L-tryptophan medium C. neoformans var. grubii and serotype AD produced a pink extracellular pigment. In contrast, for C. gattii, the pink pigment was localized intracellularly and masked by heavy production of brown pigments. Pigment production by C. neoformans var. neoformans was variable with some strains producing the pink extracellular pigment and others retained the pink pigment intracellularly. The pink intracellular pigment produced by strains of C. neoformans var. neoformans was masked by production of brown pigments. Cryptococcus laccase mutants failed to produce pigments from L-tryptophan. This is the first report that the enzyme laccase is involved in tryptophan metabolism. Prior to this report Cryptococcus laccase produced melanin or melanin like-pigments from heterocyclic compounds that contained ortho or para diphenols, diaminobenzenes and aminophenol compounds. The pigments produced from L-tryptophan were not melanin.

Pigments produced by the bacteria belonging to the genus Arthrobacter

OpenAIRE

Sutthiwong , Nuthathai; Caro , Yanis; Fouillaud , Mireille; Laurent , Philippe; Valla , A.; Dufossé , Laurent

2013-01-01

Poster communication, 7th International Congress of Pigments in Food – New technologies towards health, through colors, Novara, Italy, June 18-21, 2013.; International audience; Since several decades, pigments have been used as a taxonomic tool for the identification and classification of bacteria. Nowadays, pigment producing microorganisms have been also widely interested in scientific disciplines because of their biotechnological potential. With the growing interest in microbial pigments be...

An aeroponic culture system for the study of root herbivory on Arabidopsis thaliana

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Vaughan Martha M

2011-03-01

Full Text Available Abstract Background Plant defense against herbivory has been studied primarily in aerial tissues. However, complex defense mechanisms have evolved in all parts of the plant to combat herbivore attack and these mechanisms are likely to differ in the aerial and subterranean environment. Research investigating defense responses belowground has been hindered by experimental difficulties associated with the accessibility and quality of root tissue and the lack of bioassays using model plants with altered defense profiles. Results We have developed an aeroponic culture system based on a calcined clay substrate that allows insect herbivores to feed on plant roots while providing easy recovery of the root tissue. The culture method was validated by a root-herbivore system developed for Arabidopsis thaliana and the herbivore Bradysia spp. (fungus gnat. Arabidopsis root mass obtained from aeroponically grown plants was comparable to that from other culture systems, and the plants were morphologically normal. Bradysia larvae caused considerable root damage resulting in reduced root biomass and water absorption. After feeding on the aeroponically grown root tissue, the larvae pupated and emerged as adults. Root damage of mature plants cultivated in aeroponic substrate was compared to that of Arabidopsis seedlings grown in potting mix. Seedlings were notably more susceptible to Bradysia feeding than mature plants and showed decreased overall growth and survival rates. Conclusions A root-herbivore system consisting of Arabidopsis thaliana and larvae of the opportunistic herbivore Bradysia spp. has been established that mimics herbivory in the rhizosphere. Bradysia infestation of Arabidopsis grown in this culture system significantly affects plant performance. The culture method will allow simple profiling and in vivo functional analysis of root defenses such as chemical defense metabolites that are released in response to belowground insect attack.

Pigment Production Analysis in Human Melanoma Cells.

Science.gov (United States)

Hopkin, Amelia Soto; Paterson, Elyse K; Ruiz, Rolando; Ganesan, Anand K

2016-05-25

The human epidermal melanocyte is a highly specialized pigmented cell that serves to protect the epidermis from ultraviolet (UV) damage through the production of melanin, or melanogenesis. Misregulation in melanogenesis leading to either hyper- or hypo-pigmentation is found in human diseases such as malasma and vitiligo. Current therapies for these diseases are largely unsuccessful and the need for new therapies is necessary. In order to identify genes and or compounds that can alter melanogenesis, methods are required that can detect changes in pigment production as well as expression of key melanogenesis transcription factors and enzymes. Here we describe methods to detect changes in melanogenesis in a human melanoma cell line, MNT-1, by (1) analyzing pigment production by measuring the absorbance of melanin present by spectrophotometry, (2) analyzing transcript expression of potent regulators of melanogenesis by qunatitative reverse-transcription (RT)PCR and (3) analyzing protein expression of potent regulators of melanogenesis by Western blot (WB).

Multi-analytical study of historical semiconductor pigments

International Nuclear Information System (INIS)

Caporosso, V.

2015-01-01

This work is focused on the study of semiconductor-based pigments, which substituted traditional pigments in the second half of the 19. century. Synthetic semiconductor pigments may be chemically unstable due to the presence of many impurities unintentionally introduced during manufacturing. The aim of this work is to provide an insight on the application of X-ray Fluorescence (XRF) for the analysis of these painting materials, including both Cd- and Zn-based pigments. Three different approaches have been followed: the semi-quantitative analysis of samples with similar elemental composition, the complementary use of XRF and Raman spectroscopy for the analysis of elemental and molecular composition and the synchrotron-based XRF and XANES for the detection of impurities. The synergetic combination of different techniques provides information useful for the definition of specific markers for future analysis of paint-samples with implications for the conservation and treatment of late 19. and early 20. century paintings.

Local evolution of seed flotation in Arabidopsis.

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Susana Saez-Aguayo

2014-03-01

Full Text Available Arabidopsis seeds rapidly release hydrophilic polysaccharides from the seed coat on imbibition. These form a heavy mucilage layer around the seed that makes it sink in water. Fourteen natural Arabidopsis variants from central Asia and Scandinavia were identified with seeds that have modified mucilage release and float. Four of these have a novel mucilage phenotype with almost none of the released mucilage adhering to the seed and the absence of cellulose microfibrils. Mucilage release was modified in the variants by ten independent causal mutations in four different loci. Seven distinct mutations affected one locus, coding the MUM2 β-D-galactosidase, and represent a striking example of allelic heterogeneity. The modification of mucilage release has thus evolved a number of times independently in two restricted geographical zones. All the natural mutants identified still accumulated mucilage polysaccharides in seed coat epidermal cells. Using nuclear magnetic resonance (NMR relaxometry their production and retention was shown to reduce water mobility into internal seed tissues during imbibition, which would help to maintain seed buoyancy. Surprisingly, despite released mucilage being an excellent hydrogel it did not increase the rate of water uptake by internal seed tissues and is more likely to play a role in retaining water around the seed.

Blue Pseudoazulene-Skeleton Pigments of Natural Origin

OpenAIRE

井上, 謙一郎; イノウエ, ケンイチロウ; KENICHIRO, INOUE

1993-01-01

Genipin, an iridoid constituent of Genipa americana, readily reacts with amino acids in the presence of oxygen to give a mixture of polymeric blue pigments whose structures are not determined. In the basic studies to elucidate the structure and formation mechnism of blue pigments, the reaction of genipin with methylamine in the absence of oxygen yielded 9 red compounds leading to blue pigments. In this article, the structures and spectroscopic properties of these red compounds were described....

Genetic analysis of the gravitropic set-point angle in lateral roots of arabidopsis

Science.gov (United States)

Mullen, J. L.; Hangarter, R. P.

2003-05-01

Research on gravity responses in plants has mostly focused on primary roots and shoots, which typically orient to a vertical orientation. However, the distribution of lateral organs and their characteristically non-vertical growth orientation are critical for the determination of plant form. For example, in Arabidopsis, when lateral roots emerge from the primary root, they grow at a nearly horizontal orientation. As they elongate, the roots slowly curve until they eventually reach a vertical orientation. The regulation of this lateral root orientation is an important component affecting overall root system architecture. We found that this change in orientation is not simply due to the onset of gravitropic competence, as non-vertical lateral roots are capable of both positive and negative gravitropism. Thus, the horizontal growth of new lateral roots appears to be determined by what is called the gravitropic set-point angle (GSA). This developmental control of the GSA of lateral roots in Arabidopsis provides a useful system for investigating the components involved in regulating gravitropic responses. Using this system, we have identified several Arabidopsis mutants that have altered lateral root orientations but maintain normal primary root orientation.

Effects of jasmonic acid, ethylene, and salicylic acid signaling on the rhizosphere bacterial community of Arabidopsis thaliana.

Science.gov (United States)

Doornbos, Rogier F; Geraats, Bart P J; Kuramae, Eiko E; Van Loon, L C; Bakker, Peter A H M

2011-04-01

Systemically induced resistance is a promising strategy to control plant diseases, as it affects numerous pathogens. However, since induced resistance reduces one or both growth and activity of plant pathogens, the indigenous microflora may also be affected by an enhanced defensive state of the plant. The aim of this study was to elucidate how much the bacterial rhizosphere microflora of Arabidopsis is affected by induced systemic resistance (ISR) or systemic acquired resistance (SAR). Therefore, the bacterial microflora of wild-type plants and plants affected in their defense signaling was compared. Additionally, ISR was induced by application of methyl jasmonate and SAR by treatment with salicylic acid or benzothiadiazole. As a comparative model, we also used wild type and ethylene-insensitive tobacco. Some of the Arabidopsis genotypes affected in defense signaling showed altered numbers of culturable bacteria in their rhizospheres; however, effects were dependent on soil type. Effects of plant genotype on rhizosphere bacterial community structure could not be related to plant defense because chemical activation of ISR or SAR had no significant effects on density and structure of the rhizosphere bacterial community. These findings support the notion that control of plant diseases by elicitation of systemic resistance will not significantly affect the resident soil bacterial microflora.

The genome of Arabidopsis thaliana.

OpenAIRE

Goodman, H M; Ecker, J R; Dean, C

1995-01-01

Arabidopsis thaliana is a small flowering plant that is a member of the family cruciferae. It has many characteristics--diploid genetics, rapid growth cycle, relatively low repetitive DNA content, and small genome size--that recommend it as the model for a plant genome project. The current status of the genetic and physical maps, as well as efforts to sequence the genome, are presented. Examples are given of genes isolated by using map-based cloning. The importance of the Arabidopsis project ...

Internal pigment cells respond to external UV radiation in frogs.

Science.gov (United States)

Franco-Belussi, Lilian; Nilsson Sköld, Helen; de Oliveira, Classius

2016-05-01

Fish and amphibians have pigment cells that generate colorful skins important for signaling, camouflage, thermoregulation and protection against ultraviolet radiation (UVR). However, many animals also have pigment cells inside their bodies, on their internal organs and membranes. In contrast to external pigmentation, internal pigmentation is remarkably little studied and its function is not well known. Here, we tested genotoxic effects of UVR and its effects on internal pigmentation in a neotropical frog, Physalaemus nattereri We found increases in body darkness and internal melanin pigmentation in testes and heart surfaces and in the mesenterium and lumbar region after just a few hours of UVR exposure. The melanin dispersion in melanomacrophages in the liver and melanocytes in testes increased after UV exposure. In addition, the amount of melanin inside melanomacrophages cells also increased. Although mast cells were quickly activated by UVR, only longer UVR exposure resulted in genotoxic effects inside frogs, by increasing the frequency of micronuclei in red blood cells. This is the first study to describe systemic responses of external UVR on internal melanin pigmentation, melanomacrophages and melanocytes in frogs and thus provides a functional explanation to the presence of internal pigmentation. © 2016. Published by The Company of Biologists Ltd.

Pigment dispersion syndrome and pigmentary glaucoma--a major review.

Science.gov (United States)

Niyadurupola, Nuwan; Broadway, David C

2008-12-01

Pigment dispersion syndrome (PDS) is an interesting condition that can lead to secondary open angle glaucoma. Pigmentary glaucoma is primarily a disease of young people, myopes and men. PDS is characterized by the presence of Krukenberg spindles, iris trans-illumination defects, trabecular meshwork pigmentation and backward bowing of the iris. Posterior bowing of the iris causes rubbing of the pigmented iris epithelium against lens structures, liberation of pigment and trabecular meshwork changes that result in reduced aqueous outflow with the risk of glaucoma. Peripheral laser iridotomy can reverse backward bowing of the iris and may prevent progression of pigmentary glaucoma.

Optimization and design of pigments for heat-insulating coatings

Science.gov (United States)

Wang, Guang-Hai; Zhang, Yue

2010-12-01

This paper reports that heat insulating property of infrared reflective coatings is obtained through the use of pigments which diffuse near-infrared thermal radiation. Suitable structure and size distribution of pigments would attain maximum diffuse infrared radiation and reduce the pigment volume concentration required. The optimum structure and size range of pigments for reflective infrared coatings are studied by using Kubelka—Munk theory, Mie model and independent scattering approximation. Taking titania particle as the pigment embedded in an inorganic coating, the computational results show that core-shell particles present excellent scattering ability, more so than solid and hollow spherical particles. The optimum radius range of core-shell particles is around 0.3 ~ 1.6 μm. Furthermore, the influence of shell thickness on optical parameters of the coating is also obvious and the optimal thickness of shell is 100-300 nm.

Studies on the bio production of monascus red pigment

International Nuclear Information System (INIS)

Emam, D.A.

2007-01-01

there is an increasing interest on natural pigments to replace some currently used synthetic dyes, since the latter have been associated with toxic effects in foods. the red pigment of the fungus Monascus is widely used in all the world as food additives or pharmaceuticals. although pigment production by Monascus spp.in chemically defined media is well documented, very few information is available about the use of agro-industrial wastes. in this regard, the present study has been devoted to investigate the effect of different parameters on red pigment production by the local isolated strain of M. purpureu, in an attempt to maximize the production, and also to develop a potential fermentation process for the production of red pigment using potato processing wastewater (PPW,waters used to wash the potato slices prior to cooking in chips and crisp manufacture) as cheap production medium

Database Description - Arabidopsis Phenome Database | LSDB Archive [Life Science Database Archive metadata

Lifescience Database Archive (English)

Full Text Available List Contact us Arabidopsis Phenome Database Database Description General information of database Database n... BioResource Center Hiroshi Masuya Database classification Plant databases - Arabidopsis thaliana Organism T...axonomy Name: Arabidopsis thaliana Taxonomy ID: 3702 Database description The Arabidopsis thaliana phenome i...heir effective application. We developed the new Arabidopsis Phenome Database integrating two novel database...seful materials for their experimental research. The other, the “Database of Curated Plant Phenome” focusing

Rapid analysis of seed size in Arabidopsis for mutant and QTL discovery

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Baldwin Samantha

2011-02-01

Full Text Available Abstract Background Arabidopsis thaliana is a useful model organism for deciphering the genetic determinants of seed size; however the small size of its seeds makes measurements difficult. Bulk seed weights are often used as an indicator of average seed size, but details of individual seed is obscured. Analysis of seed images is possible but issues arise from variations in seed pigmentation and shadowing making analysis laborious. We therefore investigated the use of a consumer level scanner to facilitate seed size measurements in conjunction with open source image-processing software. Results By using the transmitted light from the slide scanning function of a flatbed scanner and particle analysis of the resulting images, we have developed a method for the rapid and high throughput analysis of seed size and seed size distribution. The technical variation due to the approach was negligible enabling us to identify aspects of maternal plant growth that contribute to biological variation in seed size. By controlling for these factors, differences in seed size caused by altered parental genome dosage and mutation were easily detected. The method has high reproducibility and sensitivity, such that a mutant with a 10% reduction in seed size was identified in a screen of endosperm-expressed genes. Our study also generated average seed size data for 91 Arabidopsis accessions and identified a number of quantitative trait loci from two recombinant inbred line populations, generated from Cape Verde Islands and Burren accessions crossed with Columbia. Conclusions This study describes a sensitive, high-throughput approach for measuring seed size and seed size distribution. The method provides a low cost and robust solution that can be easily implemented into the workflow of studies relating to various aspects of seed development.

An endoplasmic reticulum-localized Coffea arabica BURP domain-containing protein affects the response of transgenic Arabidopsis plants to diverse abiotic stresses.

Science.gov (United States)

Dinh, Sy Nguyen; Kang, Hunseung

2017-11-01

The Coffea arabica BURP domain-containing gene plays an important role in the response of transgenic Arabidopsis plants to abiotic stresses via regulating the level of diverse proteins. Although the functions of plant-specific BURP domain-containing proteins (BDP) have been determined for a few plants, their roles in the growth, development, and stress responses of most plant species, including coffee plant (Coffea arabica), are largely unknown. In this study, the function of a C. arabica BDP, designated CaBDP1, was investigated in transgenic Arabidopsis plants. The expression of CaBDP1 was highly modulated in coffee plants subjected to drought, cold, salt, or ABA. Confocal analysis of CaBDP1-GFP fusion proteins revealed that CaBDP1 is localized in the endoplasmic reticulum. The ectopic expression of CaBDP1 in Arabidopsis resulted in delayed germination of the transgenic plants under abiotic stress and in the presence of ABA. Cotyledon greening and seedling growth of the transgenic plants were inhibited in the presence of ABA due to the upregulation of ABA signaling-related genes like ABI3, ABI4, and ABI5. Proteome analysis revealed that the levels of several proteins are modulated in CaBDP1-expressing transgenic plants. The results of this study underscore the importance of BURP domain proteins in plant responses to diverse abiotic stresses.

Relative Pigment Composition and Remote Sensing Reflectance of Caribbean Shallow-Water Corals.

Directory of Open Access Journals (Sweden)

Juan L Torres-Pérez

Full Text Available Reef corals typically contain a number of pigments, mostly due to their symbiotic relationship with photosynthetic dinoflagellates. These pigments usually vary in presence and concentration and influence the spectral characteristics of corals. We studied the variations in pigment composition among seven Caribbean shallow-water Scleractinian corals by means of High Performance Liquid Chromatography (HPLC analysis to further resolve the discrimination of corals. We found a total of 27 different pigments among the coral species, including some alteration products of the main pigments. Additionally, pigments typically found in endolithic algae were also identified. A Principal Components Analysis and a Hierarchical Cluster Analysis showed the separation of coral species based on pigment composition. All the corals were collected under the same physical environmental conditions. This suggests that pigment in the coral's symbionts might be more genetically-determined than influenced by prevailing physical conditions of the reef. We further investigated the use of remote sensing reflectance (Rrs as a tool for estimating the total pigment concentration of reef corals. Depending on the coral species, the Rrs and the total symbiont pigment concentration per coral tissue area correlation showed 79.5-98.5% confidence levels demonstrating its use as a non-invasive robust technique to estimate pigment concentration in studies of coral reef biodiversity and health.

Relative Pigment Composition and Remote Sensing Reflectance of Caribbean Shallow-Water Corals.

Science.gov (United States)

Torres-Pérez, Juan L; Guild, Liane S; Armstrong, Roy A; Corredor, Jorge; Zuluaga-Montero, Anabella; Polanco, Ramón

2015-01-01

Reef corals typically contain a number of pigments, mostly due to their symbiotic relationship with photosynthetic dinoflagellates. These pigments usually vary in presence and concentration and influence the spectral characteristics of corals. We studied the variations in pigment composition among seven Caribbean shallow-water Scleractinian corals by means of High Performance Liquid Chromatography (HPLC) analysis to further resolve the discrimination of corals. We found a total of 27 different pigments among the coral species, including some alteration products of the main pigments. Additionally, pigments typically found in endolithic algae were also identified. A Principal Components Analysis and a Hierarchical Cluster Analysis showed the separation of coral species based on pigment composition. All the corals were collected under the same physical environmental conditions. This suggests that pigment in the coral's symbionts might be more genetically-determined than influenced by prevailing physical conditions of the reef. We further investigated the use of remote sensing reflectance (Rrs) as a tool for estimating the total pigment concentration of reef corals. Depending on the coral species, the Rrs and the total symbiont pigment concentration per coral tissue area correlation showed 79.5-98.5% confidence levels demonstrating its use as a non-invasive robust technique to estimate pigment concentration in studies of coral reef biodiversity and health.

Glyphosate-induced oxidative stress in Arabidopsis thaliana affecting peroxisomal metabolism and triggers activity in the oxidative phase of the pentose phosphate pathway (OxPPP) involved in NADPH generation.

Science.gov (United States)

de Freitas-Silva, Larisse; Rodríguez-Ruiz, Marta; Houmani, Hayet; da Silva, Luzimar Campos; Palma, José M; Corpas, Francisco J

2017-11-01

Glyphosate is a broad-spectrum systemic herbicide used worldwide. In susceptible plants, glyphosate affects the shikimate pathway and reduces aromatic amino acid synthesis. Using Arabidopsis seedlings grown in the presence of 20μM glyphosate, we analyzed H 2 O 2 , ascorbate, glutathione (GSH) and protein oxidation content as well as antioxidant catalase, superoxide dismutase (SOD) and ascorbate-glutathione cycle enzyme activity. We also examined the principal NADPH-generating system components, including glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), NADP-malic enzyme (NADP-ME) and NADP-isocitrate dehydrogenase (NADP-ICDH). Glyphosate caused a drastic reduction in growth parameters and an increase in protein oxidation. The herbicide also resulted in an overall increase in GSH content, antioxidant enzyme activity (catalase and all enzymatic components of the ascorbate-glutathione cycle) in addition to the two oxidative phase enzymes, G6PDH and 6PGDH, in the pentose phosphate pathway involved in NADPH generation. In this study, we provide new evidence on the participation of G6PDH and 6PGDH in the response to oxidative stress induced by glyphosate in Arabidopsis, in which peroxisomal enzymes, such as catalase and glycolate oxidase, are positively affected. We suggest that the NADPH provided by the oxidative phase of the pentose phosphate pathway (OxPPP) should serve to maintain glutathione reductase (GR) activity, thus preserving and regenerating the intracellular GSH pool under glyphosate-induced stress. It is particularly remarkable that the 6PGDH activity was unaffected by pro-oxidant and nitrating molecules such as H 2 0 2 , nitric oxide or peroxynitrite. Copyright © 2017 Elsevier GmbH. All rights reserved.

Abscisic Acid (ABA) Regulation of Arabidopsis SR Protein Gene Expression

Science.gov (United States)

Cruz, Tiago M. D.; Carvalho, Raquel F.; Richardson, Dale N.; Duque, Paula

2014-01-01

Serine/arginine-rich (SR) proteins are major modulators of alternative splicing, a key generator of proteomic diversity and flexible means of regulating gene expression likely to be crucial in plant environmental responses. Indeed, mounting evidence implicates splicing factors in signal transduction of the abscisic acid (ABA) phytohormone, which plays pivotal roles in the response to various abiotic stresses. Using real-time RT-qPCR, we analyzed total steady-state transcript levels of the 18 SR and two SR-like genes from Arabidopsis thaliana in seedlings treated with ABA and in genetic backgrounds with altered expression of the ABA-biosynthesis ABA2 and the ABA-signaling ABI1 and ABI4 genes. We also searched for ABA-responsive cis elements in the upstream regions of the 20 genes. We found that members of the plant-specific SC35-Like (SCL) Arabidopsis SR protein subfamily are distinctively responsive to exogenous ABA, while the expression of seven SR and SR-related genes is affected by alterations in key components of the ABA pathway. Finally, despite pervasiveness of established ABA-responsive promoter elements in Arabidopsis SR and SR-like genes, their expression is likely governed by additional, yet unidentified cis-acting elements. Overall, this study pinpoints SR34, SR34b, SCL30a, SCL28, SCL33, RS40, SR45 and SR45a as promising candidates for involvement in ABA-mediated stress responses. PMID:25268622

Bioavailability of nanoparticulate hematite to Arabidopsis thaliana

International Nuclear Information System (INIS)

Marusenko, Yevgeniy; Shipp, Jessie; Hamilton, George A.; Morgan, Jennifer L.L.; Keebaugh, Michael; Hill, Hansina; Dutta, Arnab; Zhuo, Xiaoding; Upadhyay, Nabin; Hutchings, James; Herckes, Pierre; Anbar, Ariel D.; Shock, Everett; Hartnett, Hilairy E.

2013-01-01

The environmental effects and bioavailability of nanoparticulate iron (Fe) to plants are currently unknown. Here, plant bioavailability of synthesized hematite Fe nanoparticles was evaluated using Arabidopsis thaliana (A. thaliana) as a model. Over 56-days of growing wild-type A. thaliana, the nanoparticle-Fe and no-Fe treatments had lower plant biomass, lower chlorophyll concentrations, and lower internal Fe concentrations than the Fe-treatment. Results for the no-Fe and nanoparticle-Fe treatments were consistently similar throughout the experiment. These results suggest that nanoparticles (mean diameter 40.9 nm, range 22.3–67.0 nm) were not taken up and therefore not bioavailable to A. thaliana. Over 14-days growing wild-type and transgenic (Type I/II proton pump overexpression) A. thaliana, the Type I plant grew more than the wild-type in the nanoparticle-Fe treatment, suggesting Type I plants cope better with Fe limitation; however, the nanoparticle-Fe and no-Fe treatments had similar growth for all plant types. -- Highlights: ► Iron nanoparticles were synthesized and assessed for bioavailability to Arabidopsis. ► Arabidopsis grew better in the presence of EDTA-bound iron than nanoparticulate iron. ► Arabidopsis grew the same in the presence of nanoparticulate iron compared to no iron. -- Synthesized iron nanoparticles were not bioavailable to Arabidopsis thaliana in agar nutrient media

Production and chemical characterization of pigments in filamentous fungi.

Science.gov (United States)

Souza, Patrícia Nirlane da Costa; Grigoletto, Tahuana Luiza Bim; de Moraes, Luiz Alberto Beraldo; Abreu, Lucas M; Guimarães, Luís Henrique Souza; Santos, Cledir; Galvão, Luciano Ribeiro; Cardoso, Patrícia Gomes

2016-01-01

Production of pigments by filamentous fungi is gaining interest owing to their use as food colourants, in cosmetics and textiles, and because of the important biological activities of these compounds. In this context, the objectives of this study were to select pigment-producing fungi, identify these fungi based on internal transcribed spacer sequences, evaluate the growth and pigment production of the selected strains on four different media, and characterize the major coloured metabolites in their extracts. Of the selected fungal strains, eight were identified as Aspergillus sydowii (CML2967), Aspergillus aureolatus (CML2964), Aspergillus keveii (CML2968), Penicillium flavigenum (CML2965), Penicillium chermesinum (CML2966), Epicoccum nigrum (CML2971), Lecanicillium aphanocladii (CML2970) and Fusarium sp. (CML2969). Fungal pigment production was influenced by medium composition. Complex media, such as potato dextrose and malt extract, favoured increased pigment production. The coloured compounds oosporein, orevactaene and dihydrotrichodimerol were identified in extracts of L. aphanocladii (CML2970), E. nigrum (CML2971), and P. flavigenum (CML2965), respectively. These results indicate that the selected fungal strains can serve as novel sources of pigments that have important industrial applications.

Analysis of ancient pigments by Raman microscopy

International Nuclear Information System (INIS)

Zuo Jian; Xu Cunyi

1999-01-01

Raman microscopy can be applied for the spatial resolution, and non-destructive in situ analysis of inorganic pigments in pottery, manuscripts and paintings. Compared with other techniques, it is the best single technique for this purpose. An overview is presented of the applications of Raman microscopy in the analysis of ancient pigments

Heterotrophic cultivation of microalgae for pigment production: A review.

Science.gov (United States)

Hu, Jianjun; Nagarajan, Dillirani; Zhang, Quanguo; Chang, Jo-Shu; Lee, Duu-Jong

Pigments (mainly carotenoids) are important nutraceuticals known for their potent anti-oxidant activities and have been used extensively as high end health supplements. Microalgae are the most promising sources of natural carotenoids and are devoid of the toxic effects associated with synthetic derivatives. Compared to photoautotrophic cultivation, heterotrophic cultivation of microalgae in well-controlled bioreactors for pigments production has attracted much attention for commercial applications due to overcoming the difficulties associated with the supply of CO 2 and light, as well as avoiding the contamination problems and land requirements in open autotrophic culture systems. In this review, the heterotrophic metabolic potential of microalgae and their uses in pigment production are comprehensively described. Strategies to enhance pigment production under heterotrophic conditions are critically discussed and the challenges faced in heterotrophic pigment production with possible alternative solutions are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

Production of Monascus pigments as extracellular crystals by cell suspension culture.

Science.gov (United States)

Lu, Fengling; Liu, Lujie; Huang, Yaolin; Zhang, Xuehong; Wang, Zhilong

2018-01-01

It is generally accepted that Monascus pigments are predominantly cell-bound, including both intracellular and surface-bound pigments. This long-term misconception was corrected in the present work. Production of extracellular crystal pigments by submerged culture of Monascus sp. was confirmed by microscopic observation and collection of Monascus pigments from extracellular broth by direct membrane filtration. Following up the new fact, the bioactivity of mycelia as whole-cell biocatalyst for biosynthesis and biodegradation of Monascus pigments had been detailedly examined in both an aqueous solution and a nonionic surfactant micelle aqueous solution. Based on those experimental results, cell suspension culture in an aqueous medium was developed as a novel strategy for accumulation of high concentration of Monascus pigments. Thus, glucose feeding during submerged culture in the aqueous medium was carried out successfully and high orange Monascus pigments concentration of near 4 g/L was achieved.

A third, ultraviolet-sensitive, visual pigment in the Tokay gecko (Gekko gekko).

Science.gov (United States)

Loew, E R

1994-06-01

Numerous extraction and microspectrophotometric studies have shown that the nocturnal Tokay gecko (Gekko gekko), has two visual pigments: a "green" with lambda max at 521 nm and a "blue" at 467 nm. In addition, similar studies on other nocturnal gecko species have found only the same two classes of visual pigment. With the finding that some diurnal species of gecko have a third visual pigment class with lambda max peaking in the UV, doubts were raised concerning the presence of only two visual pigment classes in nocturnal forms. Therefore, a microspectrophotometric re-examination of the Tokay gecko was undertaken to look specifically for a UV visual pigment. A UV-absorbing pigment (364 nm lambda max) was found in approx. 20% of the thin outer segments of type C double rods, thought previously to contain only the 467 nm pigment. That this UV-absorbing pigment was truly a visual pigment was confirmed by its dichroism, behaviour following exposure to UV radiation and "nomogram" fit. It is suggested that this visual pigment had been seen in previous microspectrophotometric studies, but its similarity to known photoproducts peaking in the same spectral region resulted in a case of mistaken identity.

Reference: 170 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available rice A et al. 2005 Mar. Plant Cell 17(3):791-803. Environmental time cues, such as photocycles (light/dark) and thermocycles...h is known about entrainment of the Arabidopsis thaliana clock to photocycles, th...e determinants of thermoperception and entrainment to thermocycles are not known. The Arabidopsis PSEUDO-RES... an oscillation after entrainment to thermocycles and to reset its clock in response to cold pulses and thus

Separation of Chloroplast Pigments Using Reverse Phase Chromatography.

Science.gov (United States)

Reese, R. Neil

1997-01-01

Presents a protocol that uses reverse phase chromatography for the separation of chloroplast pigments. Provides a simple and relatively safe procedure for use in teaching laboratories. Discusses pigment extraction, chromatography, results, and advantages of the process. (JRH)

Vibrational spectroscopic analyses of unique yellow feather pigments (spheniscins) in penguins.

Science.gov (United States)

Thomas, Daniel B; McGoverin, Cushla M; McGraw, Kevin J; James, Helen F; Madden, Odile

2013-06-06

Many animals extract, synthesize and refine chemicals for colour display, where a range of compounds and structures can produce a diverse colour palette. Feather colours, for example, span the visible spectrum and mostly result from pigments in five chemical classes (carotenoids, melanins, porphyrins, psittacofulvins and metal oxides). However, the pigment that generates the yellow colour of penguin feathers appears to represent a sixth, poorly characterized class of feather pigments. This pigment class, here termed 'spheniscin', is displayed by half of the living penguin genera; the larger and richer colour displays of the pigment are highly attractive. Using Raman and mid-infrared spectroscopies, we analysed yellow feathers from two penguin species (king penguin, Aptenodytes patagonicus; macaroni penguin, Eudyptes chrysolophus) to further characterize spheniscin pigments. The Raman spectrum of spheniscin is distinct from spectra of other feather pigments and exhibits 17 distinctive spectral bands between 300 and 1700 cm(-1). Spectral bands from the yellow pigment are assigned to aromatically bound carbon atoms, and to skeletal modes in an aromatic, heterocyclic ring. It has been suggested that the penguin pigment is a pterin compound; Raman spectra from yellow penguin feathers are broadly consistent with previously reported pterin spectra, although we have not matched it to any known compound. Raman spectroscopy can provide a rapid and non-destructive method for surveying the distribution of different classes of feather pigments in the avian family tree, and for correlating the chemistry of spheniscin with compounds analysed elsewhere. We suggest that the sixth class of feather pigments may have evolved in a stem-lineage penguin and endowed modern penguins with a costly plumage trait that appears to be chemically unique among birds.

Pigment from Streptomyces bellus MSA1 isolated from marine sediments

Science.gov (United States)

Srinivasan, M.; Merlyn Keziah, S.; Hemalatha, M.; Subathra Devi, C.

2017-11-01

The existing study is purposeful on the intracellular pigment extraction from actinomycetes isolated from Kovalam Beach regions of Chennai, Tamil Nadu, India. Only one actinobacterial isolate showed pigmented growth out of total 4 isolates. Ethyl acetate as the solvent was used in cell disruption technique for the extraction of intracellular pigments. UV-Visible spectrophotometry, FT-IR spectroscopy, HPLC and GC-MS were used for the partial characterization of the pigment. The extracted pigment was applied for the preparation of lip balm and assessing its textile dyeing property. In addition, the extracted pigment was analysed for antioxidant, antibacterial activity, MTT assay and haemolytic activity. On optimization, dextrose and maltose were the best carbon sources. The finest nitrogen sources were found to be casein and peptone. The optimum temperature range was 35°C -40°C and optimal pH was found to be between 6.0 and 8.0. The obtained results showed potent antioxidant activity and found to be non-toxic to human erythrocytes.

Studies on pigments of the myxomycete Physarum nudum. II. Separation and optical properties of the pigments from plasmodia cultured in darkness

OpenAIRE

L. Raczkowski

2015-01-01

The paper presents the data on Separation and some optical properties of the pigments obtained from the plasmodium of the myxomycete Physarum nudum grown in the dark. Pigment Separation was performed by means of thin-layer chromatography with celulose MN 300 as adsorbent and with the solvent: tert.-butylalcohol, H2O, 3N NH4OH at the ratio 5:2:1 In these conditions the chromatograms revealed 12 coloured bands from which pigments were eluted and their absorption spectra as well as the spectra o...

Colonization by the endophyte Piriformospora indica leads to early flowering in Arabidopsis thaliana likely by triggering gibberellin biosynthesis

KAUST Repository

Kim, Dongjin; Abdelaziz, Mohamad E.; Ntui, Valentine Otang; Guo, Xiujie; Al-Babili, Salim

2017-01-01

Piriformospora indica is an endophytic fungus colonizing roots of a wide variety of plants. Previous studies showed that P. indica promotes early flowering and plant growth in the medicinal plant Coleus forskohlii. To determine the impact of P. indica on flowering time in Arabidopsis, we co-cultivated the plants with P. indica under long day condition. P. indica inoculated Arabidopsis plants displayed significant early flowering phenotype. qRT-PCR analysis of colonized plants revealed an up-regulation of flowering regulatory (FLOWERING LOCUS T, LEAFY, and APETALA1) and gibberellin biosynthetic (Gibberellin 20-Oxidase2, Gibberellin 3-Oxidase1 and Gibberellin requiring1) genes, while the flowering-repressing gene FLOWERING LOCUS C was down regulated. Quantification of gibberellins content showed that the colonization with P. indica caused an increase in GA4 content. Compared to wild-type plants, inoculation of the Arabidopsis ga5 mutant affected in gibberellin biosynthetic gene led to less pronounced changes in the expression of genes regulating flowering and to a lower increase in GA4 content. Taken together, our data indicate that P. indica promotes early flowering in Arabidopsis likely by increasing gibberellin content.

Colonization by the endophyte Piriformospora indica leads to early flowering in Arabidopsis thaliana likely by triggering gibberellin biosynthesis

KAUST Repository

Kim, Dongjin

2017-06-28

Piriformospora indica is an endophytic fungus colonizing roots of a wide variety of plants. Previous studies showed that P. indica promotes early flowering and plant growth in the medicinal plant Coleus forskohlii. To determine the impact of P. indica on flowering time in Arabidopsis, we co-cultivated the plants with P. indica under long day condition. P. indica inoculated Arabidopsis plants displayed significant early flowering phenotype. qRT-PCR analysis of colonized plants revealed an up-regulation of flowering regulatory (FLOWERING LOCUS T, LEAFY, and APETALA1) and gibberellin biosynthetic (Gibberellin 20-Oxidase2, Gibberellin 3-Oxidase1 and Gibberellin requiring1) genes, while the flowering-repressing gene FLOWERING LOCUS C was down regulated. Quantification of gibberellins content showed that the colonization with P. indica caused an increase in GA4 content. Compared to wild-type plants, inoculation of the Arabidopsis ga5 mutant affected in gibberellin biosynthetic gene led to less pronounced changes in the expression of genes regulating flowering and to a lower increase in GA4 content. Taken together, our data indicate that P. indica promotes early flowering in Arabidopsis likely by increasing gibberellin content.

Change of Monascus pigment metabolism and secretion in different extractive fermentation process.

Science.gov (United States)

Chen, Gong; Tang, Rui; Tian, Xiaofei; Qin, Peng; Wu, Zhenqiang

2017-06-01

Monascus pigments that were generally produced intracellularly from Monascus spp. are important natural colorants in food industry. In this study, change of pigment metabolism and secretion was investigated through fed-batch extractive fermentation and continuous extractive fermentation. The biomass, secreting rate of pigment and total pigment yield closely correlated with the activated time of extractive fermentation as well as the composition of feeding nutrients. Metal ions played a key role in both the cell growth and pigment metabolism. Nitrogen source was necessary for a high productivity of biomass but not for high pigment yield. Furthermore, fermentation period for the fed-batch extractive fermentation could be reduced by 18.75% with a nitrogen source free feeding medium. Through a 30-day continuous extractive fermentation, the average daily productivity for total pigments reached 74.9 AU day -1 with an increase by 32.6 and 296.3% compared to that in a 6-day conventional batch fermentation and a 16-day fed-batch extractive fermentation, respectively. At the meantime, proportions of extracellular pigments increased gradually from 2.7 to 71.3%, and yellow pigments gradually became dominated in both intracellular and extracellular pigments in the end of continuous extractive fermentation. This findings showed that either fed-batch or continuous extractive fermentation acted as a promising method in the efficient production of Monascus pigments.

Complete resolution of minocycline pigmentation following a single treatment with non-ablative 1550-nm fractional resurfacing in combination with the 755-nm Q-switched alexandrite laser.

Science.gov (United States)

Vangipuram, Ramya K; DeLozier, Whitney L; Geddes, Elizabeth; Friedman, Paul M

2016-03-01

Pigmentation secondary to minocycline ingestion is an uncommon adverse event affecting 3.7-14.8% of treated individuals for which few effective therapies are available. Three patterns of minocycline pigmentation have a characteristic clinical and histological appearance. The pigment composition in each variety is different and occurs at varying skin depths. Accordingly, a tailored approach according to the type of minocycline pigmentation is crucial for treatment success. The purpose of this intervention was to evaluate the efficacy of non-ablative fractional photothermolysis in combination with the Q-switched alexandrite laser for the treatment of type I minocycline pigmentation on the face. A patient with type I minocycline pigmentation was treated with non-ablative 1550-nm fractional photothermolysis followed immediately by 755-nm Q-switched alexandrite laser and then observed clinically to determine the outcome of this modality. The patient was seen in clinic 1 month later following her single treatment session and 100% clearance of all blue facial pigment was observed. Non-ablative fractional photothermolysis in combination with the 755-nm Q-switched alexandrite laser should be considered for treatment of type I minocycline pigmentation. © 2015 Wiley Periodicals, Inc.

Arabidopsis CDS blastp result: AK108458 [KOME

Lifescience Database Archive (English)

Full Text Available AK108458 002-143-D05 At4g35000.1 L-ascorbate peroxidase 3 (APX3) identical to ascorbat...e peroxidase 3 [Arabidopsis thaliana] GI:2444019, L-ascorbate peroxidase [Arabidopsis thaliana] gi|152379...1|emb|CAA66926; similar to ascorbate peroxidase [Gossypium hirsutum] gi|1019946|gb|AAB52954 2e-35 ...

Arabidopsis CDS blastp result: AK070842 [KOME

Lifescience Database Archive (English)

Full Text Available AK070842 J023074O14 At4g35000.1 L-ascorbate peroxidase 3 (APX3) identical to ascorbat...e peroxidase 3 [Arabidopsis thaliana] GI:2444019, L-ascorbate peroxidase [Arabidopsis thaliana] gi|1523791...|emb|CAA66926; similar to ascorbate peroxidase [Gossypium hirsutum] gi|1019946|gb|AAB52954 1e-112 ...

Pigments and oligomers for inks - moving towards the best combination

International Nuclear Information System (INIS)

Hutchinson, I.; Smith, S.; Grierson, W.; Devine, E.

1999-01-01

The formulation of UV curable printing inks depends on several complex factors. If the individual components of the ink are not complementary, then performance problems can arise. One critical combination is that between the pigment and the oligomer. In a new approach to improve understanding of pigment/oligomer interactions, the resources of a pigment manufacturer and an oligomer manufacturer have been combined to investigate the problem. Initial screening of process yellow pigments and several oligomer types highlighted performance variations which were then examined in more detail

Optimization and design of pigments for heat-insulating coatings

International Nuclear Information System (INIS)

Wang Guang-Hai; Zhang Yue

2010-01-01

This paper reports that heat insulating property of infrared reflective coatings is obtained through the use of pigments which diffuse near-infrared thermal radiation. Suitable structure and size distribution of pigments would attain maximum diffuse infrared radiation and reduce the pigment volume concentration required. The optimum structure and size range of pigments for reflective infrared coatings are studied by using Kubelka—Munk theory, Mie model and independent scattering approximation. Taking titania particle as the pigment embedded in an inorganic coating, the computational results show that core-shell particles present excellent scattering ability, more so than solid and hollow spherical particles. The optimum radius range of core-shell particles is around 0.3 ∼ 1.6 μm. Furthermore, the influence of shell thickness on optical parameters of the coating is also obvious and the optimal thickness of shell is 100–300 nm. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

A comprehensive study of eco-friendly natural pigment and its applications.

Science.gov (United States)

Parmar, Ramendra Singh; Singh, Charu

2018-03-01

Actinomycetes, a large group of filamentous bacteria account for 70-80% of secondary metabolites available commercially. The present investigation was undertaken with an aim to identify and characterize pigment from actinomycetes. Actinomycetes were isolated from rhizosphere soil samples collected from different regions of Madhya Pradesh state. Out of 85 actinomycetes, only 5 actinomycetes showed pigment production and based on diffusible pigment production ability one actinomycete ARITM02 was selected. The extraction of pigment was done by solvent extraction method using methanol and purified by TLC and column chromatography. The pigment was characterized by UV-Vis spectroscopy which showed the lamda maximum of 277.44. FTIR spectroscopy suggested various functional groups like amino group, amide group, hydroxide, benzene and lactone group. The Mass spectroscopy and NMR spectroscopy showed that the molecular mass of pigment is 621.7 and molecular formula is C34H43N3O8. The pigment was also tested for Antimicrobial activity against broad spectrum human pathogens, antioxidant test and toxicity test for safe use as a natural colorant in cosmetic, food, pharmaceutical and textile industries. The conclusion of study suggested that this novel pigment could be a versatile natural, safe and multipurpose.

Unusual extensive physiologic melanin pigmentation of the oral cavity: A clinical presentation

Directory of Open Access Journals (Sweden)

K Mallikarjuna

2013-01-01

Full Text Available Pigmented lesions are commonly found in the oral cavity. Oral pigmentations may be physiological or pathological in nature. It may represent as a localized anomaly of limited significance or the presentation of potentially life threatening multisystem disease. Oral pigmentation has a multifactorial etiology. Most of the oral pigmentations are physiologic. Evaluation of a patient with pigmented lesions should include a full medical and dental history, extraoral and intraoral examinations. In this article, we report a case of extensive physiologic pigmentation of the oral cavity in a 12 year old female patient, posing a diagnostic challenge.

Reference: 398 [Arabidopsis Phenome Database[Archive

Lifescience Database Archive (English)

Full Text Available modulate the photosynthetic potential of plant cells. Identification of genes required for light-induced chloroplast movement... is beginning to define the molecular machinery that controls these movement...s. In this work, we describe plastid movement impaired 2 (pmi2), a mutant in Arabidopsis (Arabi...dopsis thaliana) that displays attenuated chloroplast movements under intermediate and high light intensitie...s while maintaining a normal movement response under low light intensities. In wi

The Effect of Static Magnetic Forces on Water Contents and Photosynthetic Pigments in Sweet Basil Ocimum basilicum L. (Lamiaceae)

Energy Technology Data Exchange (ETDEWEB)

Taia, Wafaa K; Kotbi, Abeer M [Alexandria Univ., Faculty of Science, Botany Dept., Alexandria (Egypt); AlZahrani, Hassan S [Faculty of Science, King AbdulAziz Univ., Biology Dept., Jeddah (Saudi Arabia)

2007-07-01

Three different magnetic regimes; aerial, surface and buried; each with three different forces, have been used to investigate their effects on the water contents and photosynthetic pigments of sweet basil plants (Ocimum basilicum L.). Two groups of sweet basil seeds, Ocimum basilicum L. have been cultivated, one under normal conditions and the second has been subdivided into three portion (aerial, surface and buried) to examine the effect of different magnetic forces coming from the three directions on the resulted plants. At all directions of magnets, water contents have been significantly affected by the magnetic forces. Chlorophyll A and carotene contents have been affected, as well, according to the three magnetic forces coming from soil surface regime only. Chlorophyll B did not significantly affected by differences magnetic forces in the three regimes, but it is affected by magnetism wherever its direction or force. But all the photosynthetic pigments contents (Chlorophyll A, B and Carotenes) decreased significantly than the control in the three magnetic regimes., but without any effect according to differences in the magnetic force in the aerial and burried regimes of magnetism. It was concluded that magnetism affects both water absorption and retention , the most influenced regime was the aerial magnets followed by the surface and buried ones. This result can be interpreted by the ionization of water which makes water ions respond to magnetic forces. Photosynthetic pigments have been decreased significantly by the exposure to magnetic fields, irrespective to its direction or force and this may be due to the effect of magnetic fields on the reduction in plastids inside the cells. (author)

The Effect of Static Magnetic Forces on Water Contents and Photosynthetic Pigments in Sweet Basil Ocimum basilicum L. (Lamiaceae)

International Nuclear Information System (INIS)

Taia, Wafaa K; Kotbi, Abeer M; AlZahrani, Hassan S

2007-01-01

Three different magnetic regimes; aerial, surface and buried; each with three different forces, have been used to investigate their effects on the water contents and photosynthetic pigments of sweet basil plants (Ocimum basilicum L.). Two groups of sweet basil seeds, Ocimum basilicum L. have been cultivated, one under normal conditions and the second has been subdivided into three portion (aerial, surface and buried) to examine the effect of different magnetic forces coming from the three directions on the resulted plants. At all directions of magnets, water contents have been significantly affected by the magnetic forces. Chlorophyll A and carotene contents have been affected, as well, according to the three magnetic forces coming from soil surface regime only. Chlorophyll B did not significantly affected by differences magnetic forces in the three regimes, but it is affected by magnetism wherever its direction or force. But all the photosynthetic pigments contents (Chlorophyll A, B and Carotenes) decreased significantly than the control in the three magnetic regimes., but without any effect according to differences in the magnetic force in the aerial and burried regimes of magnetism. It was concluded that magnetism affects both water absorption and retention , the most influenced regime was the aerial magnets followed by the surface and buried ones. This result can be interpreted by the ionization of water which makes water ions respond to magnetic forces. Photosynthetic pigments have been decreased significantly by the exposure to magnetic fields, irrespective to its direction or force and this may be due to the effect of magnetic fields on the reduction in plastids inside the cells. (author)

Synchrotron powder diffraction on Aztec blue pigments

Energy Technology Data Exchange (ETDEWEB)

Sanchez del Rio, M. [European Synchrotron Radiation Facility, B.P. 220, Grenoble Cedex (France); Gutierrez-Leon, A.; Castro, G.R.; Rubio-Zuazo, J. [Spanish CRG Beamline at the European Synchrotron Radiation Facility, SpLine, B.P. 220, Grenoble Cedex (France); Solis, C. [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Mexico, D.F. (Mexico); Sanchez-Hernandez, R. [INAH Subdireccion de Laboratorios y Apoyo Academico, Mexico, D.F. (Mexico); Robles-Camacho, J. [INAH Centro Regional Michoacan, Morelia, Michoacan (Mexico); Rojas-Gaytan, J. [INAH Direccion de Salvamento Arqueologico, Naucalpan de Juarez (Mexico)

2008-01-15

Some samples of raw blue pigments coming from an archaeological rescue mission in downtown Mexico City have been characterized using different techniques. The samples, some recovered as a part of a ritual offering, could be assigned to the late Aztec period (XVth century). The striking characteristic of these samples is that they seem to be raw pigments prior to any use in artworks, and it was possible to collect a few {mu}g of pigment after manual grain selection under a microscopy monitoring. All pigments are made of indigo, an organic colorant locally known as anil or xiuhquilitl. The colorant is always found in combination with an inorganic matrix, studied by powder diffraction. In one case the mineral base is palygorskite, a rare clay mineral featuring micro-channels in its structure, well known as the main ingredient of the Maya blue pigment. However, other samples present the minerals sepiolite (a clay mineral of the palygorskite family) and calcite. Another sample contains barite, a mineral never reported in prehispanic paints. We present the results of characterization using high resolution powder diffraction recorded at the European Synchrotron Radiation Facility (BM25A, SpLine beamline) complemented with other techniques. All of them gave consistent results on the composition. A chemical test on resistance to acids was done, showing a high resistance for the palygorskite and eventually sepiolite compounds, in good agreement with the excellent resistance of the Maya blue. (orig.)

Synchrotron powder diffraction on Aztec blue pigments

Science.gov (United States)

Sánchez Del Río, M.; Gutiérrez-León, A.; Castro, G. R.; Rubio-Zuazo, J.; Solís, C.; Sánchez-Hernández, R.; Robles-Camacho, J.; Rojas-Gaytán, J.

2008-01-01

Some samples of raw blue pigments coming from an archaeological rescue mission in downtown Mexico City have been characterized using different techniques. The samples, some recovered as a part of a ritual offering, could be assigned to the late Aztec period (XVth century). The striking characteristic of these samples is that they seem to be raw pigments prior to any use in artworks, and it was possible to collect a few μg of pigment after manual grain selection under a microscopy monitoring. All pigments are made of indigo, an organic colorant locally known as añil or xiuhquilitl. The colorant is always found in combination with an inorganic matrix, studied by powder diffraction. In one case the mineral base is palygorskite, a rare clay mineral featuring micro-channels in its structure, well known as the main ingredient of the Maya blue pigment. However, other samples present the minerals sepiolite (a clay mineral of the palygorskite family) and calcite. Another sample contains barite, a mineral never reported in prehispanic paints. We present the results of characterization using high resolution powder diffraction recorded at the European Synchrotron Radiation Facility (BM25A, SpLine beamline) complemented with other techniques. All of them gave consistent results on the composition. A chemical test on resistance to acids was done, showing a high resistance for the palygorskite and eventually sepiolite compounds, in good agreement with the excellent resistance of the Maya blue.

Gingival pigmentation beneath a metallic crown

International Nuclear Information System (INIS)

Sakai, T.; Hirayasu, R.; Sakai, H.; Hashimoto, N.

1988-01-01

Light and electron microscopic studies and energy dispersive X-ray analysis disclosed that the essential cause of gingival discoloration following the placement of a metallic crown, was marked deposition of melanin pigment. Deposition of melanin pigment was observed in epithelial cells, on basement membranes, and in fibroblasts, macrophages and among intercellular ground substance of the proprial layer. Brown or dark brown colored granules were observed in the deep portion of the proprial layer. Some metallic elements as silver and sulfur were detected. It was presumed that these materials were dental metals accidentally implanted in gingival tissues during the therapeutic procedure. The deposition of melanin pigment closely corresponded with mucosal tissue where these materials were present in the deep portion of the proprial layer. These findings suggested that these materials influenced the physiological metabolism of melanin and induced its pathological deposition in the proprial tissue. (author)

[Isolation and preliminary characterization of carotenoids from pink-pigmented methylotrophs].

Science.gov (United States)

Konovalova, A M; Shylin, S O; Rokytko, P V

2006-01-01

An effective method was developed for complete removal of pigments from the cells and solvent mixture for further separation of pigments using thin layer chromatography on silica gel. Carotenoid samples that have been obtained in this way are of good purity for further investigations. Carotenoid pigments of pink-pigmented facultative methylotrophic bacteria Methylobacterium have been characterized. These carotenoids are represented mainly by xanthophylls, particularly hydroxycarotenoids. Strains M. fujisawaense B-3365 and M. mesophilicum B-3352 also have nonpolar carotenes in a small amount. Physico-chemical properties of carotenoids have been studied.

The Solvent Effectiveness on Extraction Process of Seaweed Pigment

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Warkoyo Warkoyo

2011-09-01

Full Text Available Eucheuma cottonii seaweed is a species of seaweed cultured in Indonesian waters, because its cultivation is relatively easy and inexpensive. It has a wide variety of colors from green to yellow green, gray, red and brown, indicating photosynthetic pigments, such as chlorophyll and carotenoids. An important factor in the effectiveness of pigment extraction is the choice of solvent. The correct type of solvent in the extraction method of specific natural materials is important so that a pigment with optimum quality that is also benefical to the society can be produced. The target of this research is to obtain a high quality solvent type of carotenoid pigment. This research was conducted using a randomized block design with three (3 replications involving two factors namely solvent type (4 levels: aceton, ethanol, petroleum benzene, hexan & petroleum benzene and seaweed color (3 levels: brown, green and red. Research results indicated that each solvent reached a peak of maximal absorbance at  410-472 nm, namely carotenoids. The usage of acetone solvent gave the best pigment quality. Brown, green and red seaweed have pigment content of 1,28 mg/100 g; 0,98 mg/100 g; 1,35 mg/100 g and rendement of 6,24%; 4,85% and 6,65% respectively.

Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in Arabidopsis

DEFF Research Database (Denmark)

Hackenberg, Thomas; Juul, Trine Maxel; Auzina, Aija

2013-01-01

Programmed cell death often depends on generation of reactive oxygen species, which can be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants (cat2) in a screen for resistance to hydroxyurea-induced cell death. Here, we identify...... an Arabidopsis thaliana hydroxyurea-resistant autophagy mutant, atg2, which also shows reduced sensitivity to cell death triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both hydroxyurea and avrRpm1 sensitivity, we selected mutants with extremely low catalase...... activities and showed that they carried mutations in a gene that we named NO CATALASE ACTIVITY1 (NCA1). nca1 mutants showed severely reduced activities of all three catalase isoforms in Arabidopsis, and loss of NCA1 function led to strong suppression of RPM1-triggered cell death. Basal and starvation...

Ultraviolet radiation induces dose-dependent pigment dispersion in crustacean chromatophores.

Science.gov (United States)

Gouveia, Glauce Ribeiro; Lopes, Thaís Martins; Neves, Carla Amorim; Nery, Luiz Eduardo Maia; Trindade, Gilma Santos

2004-10-01

Pigment dispersion in chromatophores as a response to UV radiation was investigated in two species of crustaceans, the crab Chasmagnathus granulata and the shrimp Palaemonetes argentinus. Eyestalkless crabs and shrimps maintained on either a black or a white background were irradiated with different UV bands. In eyestalkless crabs the significant minimal effective dose inducing pigment dispersion was 0.42 J/cm(2) for UVA and 2.15 J/cm(2) for UVB. Maximal response was achieved with 10.0 J/cm(2) UVA and 8.6 J/cm(2) UVB. UVA was more effective than UVB in inducing pigment dispersion. Soon after UV exposure, melanophores once again reached the initial stage of pigment aggregation after 45 min. Aggregated erythrophores of shrimps adapted to a white background showed significant pigment dispersion with 2.5 J/cm(2) UVA and 0.29 J/cm(2) UVC. Dispersed erythrophores of shrimps adapted to a black background did not show any significant response to UVA, UVB or UVC radiation. UVB did not induce any significant pigment dispersion in shrimps adapted to either a white or a black background. As opposed to the tanning response, which only protects against future UV exposure, the pigment dispersion response could be an important agent protecting against the harmful effects of UV radiation exposure.

Mining the active proteome of Arabidopsis thaliana

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Renier A. L. Van Der Hoorn

2011-11-01

Full Text Available Assigning functions to the >30.000 proteins encoded by the Arabidopsis genome is a challenging task of the Arabidopsis Functional Genomics Network. Although genome-wide technologies like proteomics and transcriptomics have generated a wealth of information that significantly accelerated gene annotation, protein activities are poorly predicted by transcript or protein levels as protein activities are post-translationally regulated. To directly display protein activities in Arabidopsis proteomes, we developed and applied Activity-based Protein Profiling (ABPP. ABPP is based on the use of small molecule probes that react with the catalytic residues of distinct protein classes in an activity-dependent manner. Labeled proteins are separated and detected from proteins gels and purified and identified by mass spectrometry. Using probes of six different chemotypes we have displayed of activities of 76 Arabidopsis proteins. These proteins represent over ten different protein classes that contain over 250 Arabidopsis proteins, including cysteine- serine- and metallo-proteases, lipases, acyltransferases, and the proteasome. We have developed methods for identification of in vivo labeled proteins using click-chemistry and for in vivo imaging with fluorescent probes. In vivo labeling has revealed novel protein activities and unexpected subcellular activities of the proteasome. Labeling of extracts displayed several differential activities e.g. of the proteasome during immune response and methylesterases during infection. These studies illustrate the power of ABPP to display the functional proteome and testify to a successful interdisciplinary collaboration involving chemical biology, organic chemistry and proteomics.

Atmospheric CO2 Alters Resistance of Arabidopsis to Pseudomonas syringae by Affecting Abscisic Acid Accumulation and Stomatal Responsiveness to Coronatine

NARCIS (Netherlands)

Zhou, Y.; Vroegop-Vos, I.; Schuurink, R.C.; Pieterse, C.M.J.; Van Wees, S.C.M.

Atmospheric CO2 influences plant growth and stomatal aperture. Effects of high or low CO2 levels on plant disease resistance are less well understood. Here, resistance of Arabidopsis thaliana against the foliar pathogen Pseudomonas syringae pv. tomato DC3000 (Pst) was investigated at three different

Dermoscopic findings and histological correlation of the acral volar pigmented maculae in Laugier-Hunziker syndrome.

Science.gov (United States)

Sendagorta, Elena; Feito, Marta; Ramírez, Paloma; Gonzalez-Beato, María; Saida, Toshiaki; Pizarro, Angel

2010-11-01

Laugier-Hunziker syndrome (LHS) is an acquired, benign, macular hyperpigmentation of the lips and oral mucosa, often associated with pigmentation of the nails. Volar acral maculae on the palms and fingertips of patients affected by LHS are a typical feature of this rare entity. Dermoscopic examination of these maculae has been described in a previous report, in which authors found a parallel-furrow pattern. We describe two cases in which a parallel-ridge pattern (PRP) was found on the dermoscopic examination of the pigmented acral lesions. Histological examination showed increased melanin in basal keratinocytes, which was most prominent in those located at the crista intermedia profunda, that is, in the epidermal rete ridges underlying the surface ridges. In our study, dermoscopic features of the pigmented maculae found on LHS differed from those previously described. In addition, by means of this case report, the histological features of these lesions are described for the first time, showing an excellent correlation with dermoscopy. The reported cases prove that although the PRP is very specific of melanoma, it is also possible to find it in benign lesions. Therefore, we must be familiar with the differential diagnosis of PRP, and take into consideration the clinical context in which we find it. Further studies are needed to increase our knowledge on the histological and dermoscopic features of acral pigmented maculae of LHS. © 2010 Japanese Dermatological Association.

Suppression of non-photochemical quenching in Arabidopsis leaves to a ionizing radiation

International Nuclear Information System (INIS)

Yu Ran Moon; Jin-Hong Kim; Min Hee Lee; Byung Yeoup Chung; Jae-Sung Kim

2007-01-01

Complete text of publication follows. Non-photochemical quenching (NPQ) of chlorophyll fluorescence has been known to be involved in a protection of photosystems against photoinhibition through a dissipation of excess light absorbed by photosynthetic pigments. In the present study, we aimed to elucidate the effects of a ionizing radiation on NPQ by comparing alterations in the development and release of NPQ after gamma-irradiation between the wild-type (WT) and the npq1-2 mutant of Arabidopsis. The npq1-2 mutant can't develop with a normal NPQ under excess light, since it is defective in its de-epoxidase activity for conversion of violaxanthin to zeaxanthin. Gamma-irradiation with a dose of 200 Gy inhibited the development of NPQ in both the WT and mutant but more noticeably in the latter. Moreover, Fv/Fm as an indice of the photochemical efficiency of photosystem II (PSII) was almost the same in both the WT and npq1-2 mutant throughout the post-irradiation period of 5 d. The obtained results will be also discussed with those from photoinhibition induced by non-ionizing radiations such as visible light and UV-B.

Optimizing Angkak Pigments and Lovastatin Production By Monascus purpureus

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HASIM DANURI

2008-06-01

Full Text Available Angkak pigments and lovastatin had been reported very useful as natural coloring agents, as an agent to increase thrombocyte level in Dengue hemorrhagic fever, and also as a compound that was able to control blood cholesterol level. Three strains of fungus Monascus purpureus AKI, AKII, and 915 were selected to produce angkak pigments and lovastatin in potato dextrose agar (PDA medium. The best fungus strain, which is AKII, was then applied in three kinds of rice media (white rice IR-42, red rice BP-1804-IF-9, and a combination of 1:1 (w/w white IR-42 and red rice BP-1804-IF-9 for solid fermentation. The best medium and fermentation times were determined for the production of angkak pigments and lovastatin separately. Results showed that strains, media, and duration of fermentations gave significant effect on the amount of pigment produced. Strain AKII produced highest concentration of angkak pigments. The combination of rice (White IR-42 and red rice BP-1804-IF-9 produced the highest pigment than the individual white and red rie it self. The optimum duration of fermentation was 16 days for strains AKI and AKII, but only 15 days for strain 915. Therefore the strain AKII with media combination of rice and a fermentation time of 16 days were used to investigate the additional effect of various minerals. Addition of the mineral individually gave significant increased on angkak pigment production by AKII, where as the addition of minerals mixture in the forth tube did not.

Multi-element bioimaging of Arabidopsis thaliana roots

DEFF Research Database (Denmark)

Persson, Daniel Olof; Chen, Anle; Aarts, Mark G.M.

2016-01-01

Better understanding of root function is central for the development of plants with more efficient nutrient uptake and translocation. We here present a method for multielement bioimaging at the cellular level in roots of the genetic model system Arabidopsis (Arabidopsis thaliana). Using conventio......Better understanding of root function is central for the development of plants with more efficient nutrient uptake and translocation. We here present a method for multielement bioimaging at the cellular level in roots of the genetic model system Arabidopsis (Arabidopsis thaliana). Using...... omics techniques. To demonstrate the potential of the method, we analyzed a mutant of Arabidopsis unable to synthesize the metal chelator nicotianamine. The mutant accumulated substantially more zinc and manganese than the wild type in the tissues surrounding the vascular cylinder. For iron, the images...... looked completely different, with iron bound mainly in the epidermis of the wild-type plants but confined to the cortical cell walls of the mutant. The method offers the power of inductively coupled plasma-mass spectrometry to be fully employed, thereby providing a basis for detailed studies of ion...

Radiation-curable coatings containing reactive pigment dispersants

International Nuclear Information System (INIS)

Ansel, R.E.

1985-01-01

Liquid coating compositions adapted to be cured by exposure to penetrating radiation are disclosed in which a liquid vehicle of coating viscosity having an ethylenically unsaturated portion comprising one or more polyethylenically unsaturated materials adapted to cure on radiation exposure, pigment dispersed in the vehicle, and an ethylenically unsaturated radiation-curable dispersant containing a carboxyl group for wetting the pigment and assisting in the stable dipsersion of the pigment in the vehicle. This dispersant is a half amide or half ester of an ethylenically unsaturated polycarboxylic acid anhydride, such as maleic anhydride, with an organic compound having a molecular weight of from 100 to 4000 and which contains a single hydroxy group or a single amino group as the sole reactive group thereof

Pigments which reflect infrared radiation from fire

Science.gov (United States)

Berdahl, Paul H.

1998-01-01

Conventional paints transmit or absorb most of the intense infrared (IR) radiation emitted by fire, causing them to contribute to the spread of fire. The present invention comprises a fire retardant paint additive that reflects the thermal IR radiation emitted by fire in the 1 to 20 micrometer (.mu.m) wavelength range. The important spectral ranges for fire control are typically about 1 to about 8 .mu.m or, for cool smoky fires, about 2 .mu.m to about 16 .mu.m. The improved inventive coatings reflect adverse electromagnetic energy and slow the spread of fire. Specific IR reflective pigments include titanium dioxide (rutile) and red iron oxide pigments with diameters of about 1 .mu.m to about 2 .mu.m and thin leafing aluminum flake pigments.

A quadruple mutant of Arabidopsis reveals a β-carotene hydroxylation activity for LUT1/CYP97C1 and a regulatory role of xanthophylls on determination of the PSI/PSII ratio.

Science.gov (United States)

Fiore, Alessia; Dall'Osto, Luca; Cazzaniga, Stefano; Diretto, Gianfranco; Giuliano, Giovanni; Bassi, Roberto

2012-04-18

Xanthophylls are oxygenated carotenoids playing an essential role as structural components of the photosynthetic apparatus. Xanthophylls contribute to the assembly and stability of light-harvesting complex, to light absorbance and to photoprotection. The first step in xanthophyll biosynthesis from α- and β-carotene is the hydroxylation of ε- and β-rings, performed by both non-heme iron oxygenases (CHY1, CHY2) and P450 cytochromes (LUT1/CYP97C1, LUT5/CYP97A3). The Arabidopsis triple chy1chy2lut5 mutant is almost completely depleted in β-xanthophylls. Here we report on the quadruple chy1chy2lut2lut5 mutant, additionally carrying the lut2 mutation (affecting lycopene ε-cyclase). This genotype lacks lutein and yet it shows a compensatory increase in β-xanthophylls with respect to chy1chy2lut5 mutant. Mutant plants show an even stronger photosensitivity than chy1chy2lut5, a complete lack of qE, the rapidly reversible component of non-photochemical quenching, and a peculiar organization of the pigment binding complexes into thylakoids. Biochemical analysis reveals that the chy1chy2lut2lut5 mutant is depleted in Lhcb subunits and is specifically affected in Photosystem I function, showing a deficiency in PSI-LHCI supercomplexes. Moreover, by analyzing a series of single, double, triple and quadruple Arabidopsis mutants in xanthophyll biosynthesis, we show a hitherto undescribed correlation between xanthophyll levels and the PSI-PSII ratio. The decrease in the xanthophyll/carotenoid ratio causes a proportional decrease in the LHCII and PSI core levels with respect to PSII. The physiological and biochemical phenotype of the chy1chy2lut2lut5 mutant shows that (i) LUT1/CYP97C1 protein reveals a major β-carotene hydroxylase activity in vivo when depleted in its preferred substrate α-carotene; (ii) xanthophylls are needed for normal level of Photosystem I and LHCII accumulation.

A quadruple mutant of Arabidopsis reveals a β-carotene hydroxylation activity for LUT1/CYP97C1 and a regulatory role of xanthophylls on determination of the PSI/PSII ratio

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Fiore Alessia

2012-04-01

Full Text Available Abstract Background Xanthophylls are oxygenated carotenoids playing an essential role as structural components of the photosynthetic apparatus. Xanthophylls contribute to the assembly and stability of light-harvesting complex, to light absorbance and to photoprotection. The first step in xanthophyll biosynthesis from α- and β-carotene is the hydroxylation of ε- and β-rings, performed by both non-heme iron oxygenases (CHY1, CHY2 and P450 cytochromes (LUT1/CYP97C1, LUT5/CYP97A3. The Arabidopsis triple chy1chy2lut5 mutant is almost completely depleted in β-xanthophylls. Results Here we report on the quadruple chy1chy2lut2lut5 mutant, additionally carrying the lut2 mutation (affecting lycopene ε-cyclase. This genotype lacks lutein and yet it shows a compensatory increase in β-xanthophylls with respect to chy1chy2lut5 mutant. Mutant plants show an even stronger photosensitivity than chy1chy2lut5, a complete lack of qE, the rapidly reversible component of non-photochemical quenching, and a peculiar organization of the pigment binding complexes into thylakoids. Biochemical analysis reveals that the chy1chy2lut2lut5 mutant is depleted in Lhcb subunits and is specifically affected in Photosystem I function, showing a deficiency in PSI-LHCI supercomplexes. Moreover, by analyzing a series of single, double, triple and quadruple Arabidopsis mutants in xanthophyll biosynthesis, we show a hitherto undescribed correlation between xanthophyll levels and the PSI-PSII ratio. The decrease in the xanthophyll/carotenoid ratio causes a proportional decrease in the LHCII and PSI core levels with respect to PSII. Conclusions The physiological and biochemical phenotype of the chy1chy2lut2lut5 mutant shows that (i LUT1/CYP97C1 protein reveals a major β-carotene hydroxylase activity in vivo when depleted in its preferred substrate α-carotene; (ii xanthophylls are needed for normal level of Photosystem I and LHCII accumulation.

Proof-of-concept: 3D bioprinting of pigmented human skin constructs.

Science.gov (United States)

Ng, Wei Long; Qi, Jovina Tan Zhi; Yeong, Wai Yee; Naing, May Win

2018-01-23

Three-dimensional (3D) pigmented human skin constructs have been fabricated using a 3D bioprinting approach. The 3D pigmented human skin constructs are obtained from using three different types of skin cells (keratinocytes, melanocytes and fibroblasts from three different skin donors) and they exhibit similar constitutive pigmentation (pale pigmentation) as the skin donors. A two-step drop-on-demand bioprinting strategy facilitates the deposition of cell droplets to emulate the epidermal melanin units (pre-defined patterning of keratinocytes and melanocytes at the desired positions) and manipulation of the microenvironment to fabricate 3D biomimetic hierarchical porous structures found in native skin tissue. The 3D bioprinted pigmented skin constructs are compared to the pigmented skin constructs fabricated by conventional a manual-casting approach; in-depth characterization of both the 3D pigmented skin constructs has indicated that the 3D bioprinted skin constructs have a higher degree of resemblance to native skin tissue in term of the presence of well-developed stratified epidermal layers and the presence of a continuous layer of basement membrane proteins as compared to the manually-cast samples. The 3D bioprinting approach facilitates the development of 3D in vitro pigmented human skin constructs for potential toxicology testing and fundamental cell biology research.

Kinetic of orange pigment production from Monascus ruber on submerged fermentation.

Science.gov (United States)

Vendruscolo, Francielo; Schmidell, Willibaldo; de Oliveira, Débora; Ninow, Jorge Luiz

2017-01-01

Pigments produced by species of Monascus have been used to coloring rice, meat, sauces, wines and beers in East Asian countries. Monascus can produce orange (precursor), yellow and red pigments. Orange pigments have low solubility in culture media and when react with amino groups they become red and largely soluble. The orange pigments are an alternative to industrial pigment production because the low solubility facilitates the downstream operations. The aim of this work was to study the kinetic on the production of orange pigments by Monascus ruber CCT 3802. The shaking frequency of 300 rpm was favorable to production, whereas higher shaking frequencies showed negative effect. Pigment production was partially associated with cell growth, the critical dissolved oxygen concentration was between 0.894 and 1.388 mgO 2  L -1 at 30 °C, and limiting conditions of dissolved oxygen decreased the production of orange pigments. The maintenance coefficient (mo) and the conversion factor of oxygen in biomass (Yo) were 18.603 mgO 2  g x -1  h -1 and 3.133 g x  gO 2 -1 and the consideration of these parameters in the oxygen balance to estimate the biomass concentration provided good fits to the experimental data.

Pigment Cell Differentiation in Sea Urchin Blastula-Derived Primary Cell Cultures

Science.gov (United States)

Ageenko, Natalya V.; Kiselev, Konstantin V.; Dmitrenok, Pavel S.; Odintsova, Nelly A.

2014-01-01

The quinone pigments of sea urchins, specifically echinochrome and spinochromes, are known for their effective antioxidant, antibacterial, antifungal, and antitumor activities. We developed in vitro technology for inducing pigment differentiation in cell culture. The intensification of the pigment differentiation was accompanied by a simultaneous decrease in cell proliferation. The number of pigment cells was two-fold higher in the cells cultivated in the coelomic fluids of injured sea urchins than in those intact. The possible roles of the specific components of the coelomic fluids in the pigment differentiation process and the quantitative measurement of the production of naphthoquinone pigments during cultivation were examined by MALDI and electrospray ionization mass spectrometry. Echinochrome A and spinochrome E were produced by the cultivated cells of the sand dollar Scaphechinus mirabilis in all tested media, while only spinochromes were found in the cultivated cells of another sea urchin, Strongylocentrotus intermedius. The expression of genes associated with the induction of pigment differentiation was increased in cells cultivated in the presence of shikimic acid, a precursor of naphthoquinone pigments. Our results should contribute to the development of new techniques in marine biotechnology, including the generation of cell cultures producing complex bioactive compounds with therapeutic potential. PMID:24979272

Secondary pigmentary glaucoma in patients with underlying primary pigment dispersion syndrome

Directory of Open Access Journals (Sweden)

Sivaraman KR

2013-03-01

Full Text Available Kavitha R Sivaraman, Chirag G Patel, Thasarat S Vajaranant, Ahmad A ArefDepartment of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, University of Illinois at Chicago School of Medicine, Chicago, IL, USAAbstract: Primary pigment dispersion syndrome (PPDS is a bilateral condition that occurs in anatomically predisposed individuals. PPDS may evolve into pigmentary glaucoma, but it is difficult to predict which patients will progress. Secondary pigment dispersion is more often unilateral and acquired as a result of surgery, trauma, or intraocular tumor, but can likewise lead to pigmentary glaucoma. We report two cases of patients with bilateral PPDS who developed secondary pigment dispersion and pigmentary glaucoma in one eye. Patients with PPDS who acquire a secondary mechanism of pigment dispersion may be at an increased risk of progression to pigmentary glaucoma, presumably due to an increased burden of liberated pigment. In addition to regular surveillance for progression to glaucoma from PPDS, secondary causes of pigmentary dispersion in these eyes should be considered when patients present with grossly asymmetric findings. When secondary pigment dispersion is identified in eyes with PPDS, we recommend prompt intervention to alleviate the cause of secondary pigment dispersion and/or aggressive control of intraocular pressure to limit glaucomatous damage.Keywords: primary pigment dispersion syndrome, pigmentary glaucoma

Pigmentos maculares Macular pigments

Directory of Open Access Journals (Sweden)

Renata Canovas

2009-12-01

Full Text Available A luteína e a zeaxantina são pigmentos amarelos que se localizam na mácula. Devido à sua localização, diminuem e filtram a quantidade de luz principalmente azul que chega aos fotorreceptores, atuam como antioxidantes e podem melhorar a qualidade visual. Esta é uma revisão do seu mecanismo de incorporação, ação, possíveis aplicações e conhecimento científico a respeito.Lutein and Zeaxanthin are yellow pigments located at the macula. Because of your location macular pigments decrease and filter the amount of blue light that reach photoreceptors, protect the outer retina from oxidative stress and may improve the vision quality. This is a review regarding incorporation mechanism, function and knowledge update.

Secondary pigmentary glaucoma in patients with underlying primary pigment dispersion syndrome.

Science.gov (United States)

Sivaraman, Kavitha R; Patel, Chirag G; Vajaranant, Thasarat S; Aref, Ahmad A

2013-01-01

Primary pigment dispersion syndrome (PPDS) is a bilateral condition that occurs in anatomically predisposed individuals. PPDS may evolve into pigmentary glaucoma, but it is difficult to predict which patients will progress. Secondary pigment dispersion is more often unilateral and acquired as a result of surgery, trauma, or intraocular tumor, but can likewise lead to pigmentary glaucoma. We report two cases of patients with bilateral PPDS who developed secondary pigment dispersion and pigmentary glaucoma in one eye. Patients with PPDS who acquire a secondary mechanism of pigment dispersion may be at an increased risk of progression to pigmentary glaucoma, presumably due to an increased burden of liberated pigment. In addition to regular surveillance for progression to glaucoma from PPDS, secondary causes of pigmentary dispersion in these eyes should be considered when patients present with grossly asymmetric findings. When secondary pigment dispersion is identified in eyes with PPDS, we recommend prompt intervention to alleviate the cause of secondary pigment dispersion and/or aggressive control of intraocular pressure to limit glaucomatous damage.

Monascus: a Reality on the Production and Application of Microbial Pigments.

Science.gov (United States)

Vendruscolo, Francielo; Meinicke Bühler, Rose Marie; Cesar de Carvalho, Júlio; de Oliveira, Débora; Moritz, Denise Estevez; Schmidell, Willibaldo; Ninow, Jorge Luiz

2016-01-01

Monascus species can produce yellow, orange, and red pigments, depending on the employed cultivation conditions. They are classified as natural pigments and can be applied for coloration of meat, fishes, cheese, beer, and pates, besides their use in inks for printer and dyes for textile, cosmetic, and pharmaceutical industries. These natural pigments also present antimicrobial activity on pathogenic microorganisms and other beneficial effects to the health as antioxidant and anticholesterol activities. Depending on the substrates, the operational conditions (temperature, pH, dissolved oxygen), and fermentation mode (state solid fermentation or submerged fermentation), the production can be directed for one specific color dye. This review has a main objective to present an approach of Monascus pigments as a reality to obtaining and application of natural pigments by microorganisms, as to highlight properties that makes this pigment as promising for worldwide industrial applications.

Melatonin signaling affects the timing in the daily rhythm of phagocytic activity by the retinal pigment epithelium.

Science.gov (United States)

Laurent, Virgine; Sengupta, Anamika; Sánchez-Bretaño, Aída; Hicks, David; Tosini, Gianluca

2017-12-01

Earlier studies in Xenopus have indicated a role for melatonin in the regulation of retinal disk shedding, but the role of melatonin in the regulation of daily rhythm in mammalian disk shedding and phagocytosis is still unclear. We recently produced a series of transgenic mice lacking melatonin receptor type 1 (MT 1 ) or type 2 (MT 2 ) in a melatonin-proficient background and have shown that removal of MT 1 and MT 2 receptors induces significant effects on daily and circadian regulation of the electroretinogram as well as on the viability of photoreceptor cells during aging. In this study we investigated the daily rhythm of phagocytic activity by the retinal pigment epithelium in MT 1 and MT 2 knock-out mice. Our data indicate that in MT 1 and MT 2 knock-out mice the peak of phagocytosis is advanced by 3 h with respect to wild-type mice and occurred in dark rather than after the onset of light, albeit the mean phagocytic activity over the 24-h period did not change among the three genotypes. Nevertheless, this small change in the profile of daily phagocytic rhythms may produce a significant effect on retinal health since MT 1 and MT 2 knock-out mice showed a significant increase in lipofuscin accumulation in the retinal pigment epithelium. Copyright © 2017 Elsevier Ltd. All rights reserved.

Self-Normalized Photoacoustic Technique for the Quantitative Analysis of Paper Pigments

Science.gov (United States)

Balderas-López, J. A.; Gómez y Gómez, Y. M.; Bautista-Ramírez, M. E.; Pescador-Rojas, J. A.; Martínez-Pérez, L.; Lomelí-Mejía, P. A.

2018-03-01

A self-normalized photoacoustic technique was applied for quantitative analysis of pigments embedded in solids. Paper samples (filter paper, Whatman No. 1), attached with the pigment: Direct Fast Turquoise Blue GL, were used for this study. This pigment is a blue dye commonly used in industry to dye paper and other fabrics. The optical absorption coefficient, at a wavelength of 660 nm, was measured for this pigment at various concentrations in the paper substrate. It was shown that Beer-Lambert model for light absorption applies well for pigments in solid substrates and optical absorption coefficients as large as 220 cm^{-1} can be measured with this photoacoustic technique.

Different myrosinase and idioblast distribution in Arabidopsis and Brassica napus

DEFF Research Database (Denmark)

Andreasson, Erik; Jørgensen, Lise Bolt; Höglund, Anna-Stina

2001-01-01

Arabidopsis, Brassica napus, Myrosinase, Myrosinase Binding Protein, Glucosinolates, Myrosin Cell, Immunocytochemistry......Arabidopsis, Brassica napus, Myrosinase, Myrosinase Binding Protein, Glucosinolates, Myrosin Cell, Immunocytochemistry...

The applications of VIP 397/418 bulbs in free radical white pigmented coatings: UV curing evaluation for different free radical white pigmented formulations (I)

International Nuclear Information System (INIS)

Rong Bao; McCartney, R.

1999-01-01

White pigmented coatings have gained commercial success using a Gallium doped microwave F600-V bulb. A novel VIP 397/418 bulb has been made recently, by Fusion UV Systems, to increase UV curing efficiency of white pigmented coatings. Previous research work has shown that the VIP 397/418 bulb can cure cationic white pigmented coatings 40-60% faster than a F600-V bulb. Further evaluations of free radical white pigmented coatings have produced significant data indicating that better physical properties (40-50%) or higher cure speeds (50%) can be obtained by using the VIP 397/418 bulb than a F600-V bulb

Quantitative analysis of ancient Egyptian pigments by external PIXE

International Nuclear Information System (INIS)

Uda, M.; Tsunokami, T.; Murai, R.; Maeda, K.; Harigai, I.; Nakayama, Y.; Yoshimura, S.; Kikuchi, T.; Sakurai, K.; Sasa, Y.

1993-01-01

Pigments painted on Egyptian excavations in the 18th Dynasty were analyzed successfully by external PIXE with the aid of the X-ray diffraction. A white pigment was composed on Mg 3 Ca(CO 3 ) 4 ; red: αFe 2 O 3 , αFeO.OH and AsS; pink: Mixtures of white and red pigments; yellow: αFeO.OH and As 2 S 3 ; and blue: CaO.CuO.4SiO 2 . (orig.)

MRI diagnosis of pigmented villonodular synovitis

International Nuclear Information System (INIS)

Shang Zhongpu; Sui Zhengyan; Xue Jianrong; Song Cuizhi; Liu Yuekui; Li Jinwang

2007-01-01

Objective: To explore the MRI characteristics of pigmented villonodular synovitis. Methods: MRI and clinic data of 14 patients with pigmented villonodular synovitis proved by pathology were reviewed retrospectively. Results: MRI showed diffusible lesions in all 14 cases. 12 cases were located in knee joint, 2 in hip. MRI revealed nodules and masses formed by villis hyperplasia in the joints. MRI demonstrated the nodules with slightly low signal intensity on both T 1 WI and T 2 WI in 13 cases, the destruction of the cartilage in 8 cases, the destruction of the ligament in 5 cases, and the hydropsy in joint cavity in 10 cases, the destruction of the meniscus in 2 cases. Conclusion: The typical features of pigmented villonodular synovitis on MRI revealed the nodules formed by villis hyperplasia in the joint. Hemosiderin in the nodules demonstrated slightly low signal intensity on both T 1 WI and T 2 WI, with the presence of typical features like 'foam rubber cushion' sign and 'lichen' sign. (authors)

Optimization of fermentation conditions for red pigment production ...

African Journals Online (AJOL)

An extracellular pigment-producing ascomycetous filamentous fungi belonging to the genera Penicillium was obtained from soil and its optimal culture conditions investigated. The optimal culture conditions for pigment production were as follows; soluble starch 2% (670 units), peptone (880 units), pH 9.0 (900 units); ...

Preparation of nano-iron oxide red pigment powders by use of cyanided tailings

International Nuclear Information System (INIS)

Li Dengxin; Gao Guolong; Meng Fanling; Ji Chong

2008-01-01

On one hand, cyanided tailings are one kind of pollutants. On the other hand, they contain a lot of valuable elements. So utilization of them can bring social and environmental benefits. In this paper, cyanided tailings were used to prepare nano-iron oxide red pigment powders by an ammonia process with urea as precipitant. At first, cyanided tailings were oxidized by nitric acid. Then, the oxidizing mixture was separated into solid and liquid parts. The liquid mixture was reduced by scrap iron and the impurity of it was removed by use of NH 3 .H 2 O. Then, the seed crystal of γ-FeOOH was obtained, when the pure liquid reacted with ammonia liquid at the selected experimental conditions. At last, nano-iron oxide red pigment powders were prepared. The structure, morphology and size distribution of seed crystal and iron oxide red were characterized systematically by means of X-ray diffraction (XRD), transmission electron microscope (TEM) and laser particle size analyzer (LPSA). The results revealed that typical iron oxide nanoparticles were α-Fe 2 O 3 with particle size of 50-70 nm. Furthermore, the factors that affected the hue and quality of the seed crystal and iron oxide red pigment were also discussed

The Reaumuria trigyna transcription factor RtWRKY1 confers tolerance to salt stress in transgenic Arabidopsis.

Science.gov (United States)

Du, Chao; Zhao, Pingping; Zhang, Huirong; Li, Ningning; Zheng, Linlin; Wang, Yingchun

2017-08-01

Reaumuria trigyna (R. trigyna) is an endangered small shrub endemic to the Eastern Alxa-Western Ordos area in Inner Mongolia, China. Based on R. trigyna transcriptome data, the Group I WRKY transcription factor gene RtWRKY1 was cloned from R. trigyna. The full-length RtWRKY1 gene was 2100bp, including a 1261-bp open reading frame (ORF) encoding 573 amino acids. RtWRKY1 was mainly expressed in the stem and was induced by salt, cold stress, and ABA treatment. Overexpression of RtWRKY1 in Arabidopsis significantly enhanced the chlorophyll content, root length, and fresh weight of the transgenic lines under salt stress. RtWRKY1 transgenic Arabidopsis exhibited higher proline content, GSH-PX, POD, SOD, and CAT activities, and lower MDA content, Na + content, and Na + /K + ratio than wild-type Arabidopsis under salt stress conditions. Salt stress affected the expression of ion transport, proline biosynthesis, and antioxidant related genes, including AtAPX1, AtCAT1, AtSOD1, AtP5CS1, AtP5CS2, AtPRODH1, AtPRODH2, and AtSOS1 in transgenic lines. RtWRKY1 confers tolerance to salt stress in transgenic Arabidopsis by regulating plant growth, osmotic balance, Na + /K + homeostasis, and the antioxidant system. Copyright © 2017 Elsevier GmbH. All rights reserved.

[Is prophylactic YAG iridotomy useful in pigment dispersion syndrome?].

Science.gov (United States)

Rosentreter, A; Schwenn, O; Funk, J; Dietlein, T

2013-04-01

Despite theoretical considerations concerning the advantage of iridotomy in eyes with pigment dispersion syndrome or early pigment glaucoma, there is a lack of clinical evidence that this procedure has a long-term effect in preventing glaucoma damage under these circumstances. However, several factors may contribute to this lack of evidence, e.g. the statistical problem of a low conversion rate from pigment dispersion syndrome to pigment glaucoma or the inclusion criteria in the studies treating patients older than 40 years or genetic dispositions in pigment glaucoma that are not yet fully clear. On the basis of current data the decision for YAG iridotomy should only be taken in patients younger than 40 years, if the midperipheral iris shows an inverse bowing and the intraocular pressure is normal or slightly increased with no progressive signs of optic nerve damage. In cases of insufficient intraocular pressure and visual defects due to glaucomatous optic nerve damage, incisional glaucoma surgery is usually necessary especially in younger patients with a long life expectancy.

Fly ash based zeolitic pigments for application in anticorrosive paints

International Nuclear Information System (INIS)

Shaw, Ruchi; Tiwari, Sangeeta

2016-01-01

The purpose of this work is to evaluate the utilization of waste fly ash in anticorrosive paints. Zeolite NaY was synthesized from waste fly ash and subsequently modified by exchanging its nominal cation Na + with Mg 2+ and Ca 2+ ions. The metal ion exchanged zeolite was then used as anticorrosive zeolitic pigments in paints. The prepared zeolite NaY was characterized using X-Ray diffraction technique and Scanning electron microscopy. The size, shape and density of the prepared fly ash based pigments were determined by various techniques. The paints were prepared by using fly ash based zeolitic pigments in epoxy resin and the percentages of pigments used in paints were 2% and 5%. These paints were applied to the mild steel panels and the anticorrosive properties of the pigments were assessed by the electrochemical spectroscopy technique (EIS).

An Inverse Modeling Approach to Estimating Phytoplankton Pigment Concentrations from Phytoplankton Absorption Spectra

Science.gov (United States)

Moisan, John R.; Moisan, Tiffany A. H.; Linkswiler, Matthew A.

2011-01-01

Phytoplankton absorption spectra and High-Performance Liquid Chromatography (HPLC) pigment observations from the Eastern U.S. and global observations from NASA's SeaBASS archive are used in a linear inverse calculation to extract pigment-specific absorption spectra. Using these pigment-specific absorption spectra to reconstruct the phytoplankton absorption spectra results in high correlations at all visible wavelengths (r(sup 2) from 0.83 to 0.98), and linear regressions (slopes ranging from 0.8 to 1.1). Higher correlations (r(sup 2) from 0.75 to 1.00) are obtained in the visible portion of the spectra when the total phytoplankton absorption spectra are unpackaged by multiplying the entire spectra by a factor that sets the total absorption at 675 nm to that expected from absorption spectra reconstruction using measured pigment concentrations and laboratory-derived pigment-specific absorption spectra. The derived pigment-specific absorption spectra were further used with the total phytoplankton absorption spectra in a second linear inverse calculation to estimate the various phytoplankton HPLC pigments. A comparison between the estimated and measured pigment concentrations for the 18 pigment fields showed good correlations (r(sup 2) greater than 0.5) for 7 pigments and very good correlations (r(sup 2) greater than 0.7) for chlorophyll a and fucoxanthin. Higher correlations result when the analysis is carried out at more local geographic scales. The ability to estimate phytoplankton pigments using pigment-specific absorption spectra is critical for using hyperspectral inverse models to retrieve phytoplankton pigment concentrations and other Inherent Optical Properties (IOPs) from passive remote sensing observations.

The concave iris in pigment dispersion syndrome.

Science.gov (United States)

Liu, Lance; Ong, Ee Lin; Crowston, Jonathan

2011-01-01

To visualize the changes of the iris contour in patients with pigment dispersion syndrome after blinking, accommodation, and pharmacologic miosis using anterior segment optical coherence tomography. Observational case series. A total of 33 eyes of 20 patients with pigment dispersion syndrome. Each eye was imaged along the horizontal 0- to 180-degree meridian using the Visante Anterior Segment Imaging System (Carl Zeiss Meditec, Dublin, CA). Scans were performed at baseline and after focusing on an internal fixation target for 5 minutes, forced blinking, accommodation, and pharmacologic miosis with pilocarpine 2%. Quantitative analysis of the changes in the iris configuration. After 5 minutes of continual fixation, the iris became planar with the mean ± standard deviation curvature decreasing from 214 ± 74 μm to 67 ± 76 μm (P pigment dispersion syndrome after forced blinking, but the iris concavity recovered to 227 ± 113 μm (P = 0.34) and 238 ± 119 μm (P = 0.19) with the -3.0 and -6.0 diopter lenses, respectively. Pilocarpine-induced miosis caused the iris to assume a planar configuration in all subjects. This study shows that the iris in pigment dispersion syndrome assumes a planar configuration when fixating and that the concavity of the iris surface is not restored by blinking. Accommodation restored the iris concavity, suggesting that the posterior curvature of the iris in pigment dispersion syndrome is induced and probably maintained, at least in part, by accommodation. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Multiscale digital Arabidopsis predicts individual organ and whole-organism growth.

Science.gov (United States)

Chew, Yin Hoon; Wenden, Bénédicte; Flis, Anna; Mengin, Virginie; Taylor, Jasper; Davey, Christopher L; Tindal, Christopher; Thomas, Howard; Ougham, Helen J; de Reffye, Philippe; Stitt, Mark; Williams, Mathew; Muetzelfeldt, Robert; Halliday, Karen J; Millar, Andrew J

2014-09-30

Understanding how dynamic molecular networks affect whole-organism physiology, analogous to mapping genotype to phenotype, remains a key challenge in biology. Quantitative models that represent processes at multiple scales and link understanding from several research domains can help to tackle this problem. Such integrated models are more common in crop science and ecophysiology than in the research communities that elucidate molecular networks. Several laboratories have modeled particular aspects of growth in Arabidopsis thaliana, but it was unclear whether these existing models could productively be combined. We test this approach by constructing a multiscale model of Arabidopsis rosette growth. Four existing models were integrated with minimal parameter modification (leaf water content and one flowering parameter used measured data). The resulting framework model links genetic regulation and biochemical dynamics to events at the organ and whole-plant levels, helping to understand the combined effects of endogenous and environmental regulators on Arabidopsis growth. The framework model was validated and tested with metabolic, physiological, and biomass data from two laboratories, for five photoperiods, three accessions, and a transgenic line, highlighting the plasticity of plant growth strategies. The model was extended to include stochastic development. Model simulations gave insight into the developmental control of leaf production and provided a quantitative explanation for the pleiotropic developmental phenotype caused by overexpression of miR156, which was an open question. Modular, multiscale models, assembling knowledge from systems biology to ecophysiology, will help to understand and to engineer plant behavior from the genome to the field.

[Spectral sensitivity and visual pigments of the coastal crab Hemigrapsus sanguineus].

Science.gov (United States)

Shukoliukov, S A; Zak, P P; Kalamkarov, G R; Kalishevich, O O; Ostrovskiĭ, M A

1980-01-01

It has been shown that the compound eye of the coastal crab has one photosensitive pigment rhodopsin and screening pigments, black and orange one. The orange pigment has lambda max = 480 nm, rhodopsin in digitonin is stable towards hydroxylamin action, has lambda max = 490-495 nm and after bleaching is transformed into free retinene and opsin. The pigments with lambda max = 430 and 475 nm of the receptor part of the eye are also solubilized. These pigments are not photosensitive but they dissociate under the effect of hydroxylamine. The curye of spectral sensitivity of the coastal crab has the basic maximum at approximately 525 nm and the additional one at 450 nm, which seems to be provided by a combination of the visual pigment--rhodopsin (lambda max 500 nm) with a carotinoid filter (lambda max 480-490). Specific features of the visual system of coastal crab are discussed.

Transcriptome analysis of the exocarp of apple fruit identifies light-induced genes involved in red color pigmentation.

Science.gov (United States)

Vimolmangkang, Sornkanok; Zheng, Danman; Han, Yuepeng; Khan, M Awais; Soria-Guerra, Ruth Elena; Korban, Schuyler S

2014-01-15

Although the mechanism of light regulation of color pigmentation of apple fruit is not fully understood, it has been shown that light can regulate expression of genes in the anthocyanin biosynthesis pathway by inducing transcription factors (TFs). Moreover, expression of genes encoding enzymes involved in this pathway may be coordinately regulated by multiple TFs. In this study, fruits on trees of apple cv. Red Delicious were covered with paper bags during early stages of fruit development and then removed prior to maturation to analyze the transcriptome in the exocarp of apple fruit. Comparisons of gene expression profiles of fruit covered with paper bags (dark-grown treatment) and those subjected to 14 h light treatment, following removal of paper bags, were investigated using an apple microarray of 40,000 sequences. Expression profiles were investigated over three time points, at one week intervals, during fruit development. Overall, 736 genes with expression values greater than two-fold were found to be modulated by light treatment. Light-induced products were classified into 19 categories with highest scores in primary metabolism (17%) and transcription (12%). Based on the Arabidopsis gene ontology annotation, 18 genes were identified as TFs. To further confirm expression patterns of flavonoid-related genes, these were subjected to quantitative RT-PCR (qRT-PCR) using fruit of red-skinned apple cv. Red Delicious and yellow-skinned apple cv. Golden Delicious. Of these, two genes showed higher levels of expression in 'Red Delicious' than in 'Golden Delicious', and were likely involved in the regulation of fruit red color pigmentation. © 2013 Elsevier B.V. All rights reserved.

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms

KAUST Repository

Park, Hyo-Young

2017-04-21

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion. The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3\\' splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins\\' Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms

KAUST Repository

Park, Hyo-Young; Lee, Keh Chien; Jang, Yun Hee; Kim, SoonKap; Thu, May Phyo; Lee, Jeong Hwan; Kim, Jeong-Kook

2017-01-01

The Arabidopsis splicing factors, AtU2AF65, AtU2AF35, and AtSF1 shuttle between nuclei and cytoplasms. These proteins also move rapidly and continuously in the nuclei, and their movements are affected by ATP depletion. The U2AF65 proteins are splicing factors that interact with SF1 and U2AF35 proteins to promote U2snRNP for the recognition of the pre-mRNA 3' splice site during early spliceosome assembly. We have determined the subcellular localization and movement of these proteins' Arabidopsis homologs. It was found that Arabidopsis U2AF65 homologs, AtU2AF65a, and AtU2AF65b proteins interact with AtU2AF35a and AtU2AF35b, which are Arabidopsis U2AF35 homologs. We have examined the mobility of these proteins including AtSF1 using fluorescence recovery after photobleaching and fluorescence loss in photobleaching analyses. These proteins displayed dynamic movements in nuclei and their movements were affected by ATP depletion. We have also demonstrated that these proteins shuttle between nuclei and cytoplasms, suggesting that they may also function in cytoplasm. These results indicate that such splicing factors show very similar characteristics to their human counterparts, suggesting evolutionary conservation.

Molecular signatures in Arabidopsis thaliana in response to insect attack and bacterial infection.

Science.gov (United States)

Barah, Pankaj; Winge, Per; Kusnierczyk, Anna; Tran, Diem Hong; Bones, Atle M

2013-01-01

Under the threat of global climatic change and food shortages, it is essential to take the initiative to obtain a comprehensive understanding of common and specific defence mechanisms existing in plant systems for protection against different types of biotic invaders. We have implemented an integrated approach to analyse the overall transcriptomic reprogramming and systems-level defence responses in the model plant species Arabidopsis thaliana (A. thaliana henceforth) during insect Brevicoryne brassicae (B. brassicae henceforth) and bacterial Pseudomonas syringae pv. tomato strain DC3000 (P. syringae henceforth) attacks. The main aim of this study was to identify the attacker-specific and general defence response signatures in A. thaliana when attacked by phloem-feeding aphids or pathogenic bacteria. The obtained annotated networks of differentially expressed transcripts indicated that members of transcription factor families, such as WRKY, MYB, ERF, BHLH and bZIP, could be crucial for stress-specific defence regulation in Arabidopsis during aphid and P. syringae attack. The defence response pathways, signalling pathways and metabolic processes associated with aphid attack and P. syringae infection partially overlapped. Components of several important biosynthesis and signalling pathways, such as salicylic acid (SA), jasmonic acid (JA), ethylene (ET) and glucosinolates, were differentially affected during the two the treatments. Several stress-regulated transcription factors were known to be associated with stress-inducible microRNAs. The differentially regulated gene sets included many signature transcription factors, and our co-expression analysis showed that they were also strongly co-expressed during 69 other biotic stress experiments. Defence responses and functional networks that were unique and specific to aphid or P. syringae stresses were identified. Furthermore, our analysis revealed a probable link between biotic stress and microRNAs in Arabidopsis and

Molecular signatures in Arabidopsis thaliana in response to insect attack and bacterial infection.

Directory of Open Access Journals (Sweden)

Pankaj Barah

Full Text Available BACKGROUND: Under the threat of global climatic change and food shortages, it is essential to take the initiative to obtain a comprehensive understanding of common and specific defence mechanisms existing in plant systems for protection against different types of biotic invaders. We have implemented an integrated approach to analyse the overall transcriptomic reprogramming and systems-level defence responses in the model plant species Arabidopsis thaliana (A. thaliana henceforth during insect Brevicoryne brassicae (B. brassicae henceforth and bacterial Pseudomonas syringae pv. tomato strain DC3000 (P. syringae henceforth attacks. The main aim of this study was to identify the attacker-specific and general defence response signatures in A. thaliana when attacked by phloem-feeding aphids or pathogenic bacteria. RESULTS: The obtained annotated networks of differentially expressed transcripts indicated that members of transcription factor families, such as WRKY, MYB, ERF, BHLH and bZIP, could be crucial for stress-specific defence regulation in Arabidopsis during aphid and P. syringae attack. The defence response pathways, signalling pathways and metabolic processes associated with aphid attack and P. syringae infection partially overlapped. Components of several important biosynthesis and signalling pathways, such as salicylic acid (SA, jasmonic acid (JA, ethylene (ET and glucosinolates, were differentially affected during the two the treatments. Several stress-regulated transcription factors were known to be associated with stress-inducible microRNAs. The differentially regulated gene sets included many signature transcription factors, and our co-expression analysis showed that they were also strongly co-expressed during 69 other biotic stress experiments. CONCLUSIONS: Defence responses and functional networks that were unique and specific to aphid or P. syringae stresses were identified. Furthermore, our analysis revealed a probable link between

Chlorophyll: The wonder pigment

Digital Repository Service at National Institute of Oceanography (India)

Bhat, S.R.

Chlorophyll, the green plant pigment, a 'real life force' of living beings, besides synthesizing food, is a great source of vitamins, minerals and other phytochemicals. Adding chlorophyll rich food to our diet fortifies our body against health...

Barumiki antocyjanowe u Iris germanica [Anthocyanin pigments in Iris germanica L.

Directory of Open Access Journals (Sweden)

J. Szczepańska

2015-06-01

Full Text Available Anthocyanin pigments occurring in the flowers of Iris germanica were investigated in five varieties: Rota, Wedgewood, Empress of India, Deputate Nomblot and Joanna. The relation between the colour of the flower and the amount of the pigment was studied. The pigments were extracted from the dry plant material with 1% hydrochloric acid in methanol. Paper chromatography and colorimetric determinations were used for identification of the pigments and their quantitative determination. The results allow the following conclusions: 1. The varieties investigated were characterized toy the occurrence of delphinidine glycoside; 2. The colour intensity is dependent on the anthocyanin pigments; 3. The colour spectrum of Iris sp. flowersis greatly extended by yellow copigments.

Natural genetic variation in Arabidopsis thaliana defense metabolism genes modulates field fitness.

Science.gov (United States)

Kerwin, Rachel; Feusier, Julie; Corwin, Jason; Rubin, Matthew; Lin, Catherine; Muok, Alise; Larson, Brandon; Li, Baohua; Joseph, Bindu; Francisco, Marta; Copeland, Daniel; Weinig, Cynthia; Kliebenstein, Daniel J

2015-04-13

Natural populations persist in complex environments, where biotic stressors, such as pathogen and insect communities, fluctuate temporally and spatially. These shifting biotic pressures generate heterogeneous selective forces that can maintain standing natural variation within a species. To directly test if genes containing causal variation for the Arabidopsis thaliana defensive compounds, glucosinolates (GSL) control field fitness and are therefore subject to natural selection, we conducted a multi-year field trial using lines that vary in only specific causal genes. Interestingly, we found that variation in these naturally polymorphic GSL genes affected fitness in each of our environments but the pattern fluctuated such that highly fit genotypes in one trial displayed lower fitness in another and that no GSL genotype or genotypes consistently out-performed the others. This was true both across locations and within the same location across years. These results indicate that environmental heterogeneity may contribute to the maintenance of GSL variation observed within Arabidopsis thaliana.

Unraveling the chemical identity of meat pigments.

Science.gov (United States)

Pegg, R B; Shahidi, F

1997-10-01

This review examines the chemistry of nitrite curing of meat and meat products as it relates to the development of cured meat color and provides a detailed account of how nitrite-free processed meats could be prepared using the preformed cooked cured-meat pigment (CCMP). Thus, a chemical description of meat color, both raw and cooked, and characterization of nitrosylheme pigments follows. Based on electron paramagnetic resonance (EPR), visible and infrared spectroscopic studies, evidence has been provided to support the hypothesis that the chemical structure of the preformed CCMP is identical to that of the pigment prepared in situ after thermal processing of nitrite-cured meat and is in fact a mononitrosylheme complex. An appendix, which describes the basic principles of EPR spectroscopy used in the context of this review, is attached.

Corneal collagen crosslinking and pigment dispersion syndrome.

Science.gov (United States)

LaHood, Benjamin R; Moore, Sacha

2017-03-01

We describe the case of a keratoconus patient with pigment dispersion syndrome (PDS) who was treated for progressive corneal ectasia with corneal collagen crosslinking (CXL). Pigment dispersion syndrome has been shown to have associated morphologic changes of the corneal endothelium. Corneal CXL has the potential to cause toxicity to the corneal endothelium, and adjacent pigment might increase the likelihood of damage. In this case, the presence of PDS had no detrimental effect on the outcome of treatment, and no complications were observed at 12 months follow-up, indicating that it may be safe to perform corneal CXL in the setting of PDS. This is an important observation as the number of indications for corneal CXL grows. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Standardized Method for High-throughput Sterilization of Arabidopsis Seeds.

Science.gov (United States)

Lindsey, Benson E; Rivero, Luz; Calhoun, Chistopher S; Grotewold, Erich; Brkljacic, Jelena

2017-10-17

Arabidopsis thaliana (Arabidopsis) seedlings often need to be grown on sterile media. This requires prior seed sterilization to prevent the growth of microbial contaminants present on the seed surface. Currently, Arabidopsis seeds are sterilized using two distinct sterilization techniques in conditions that differ slightly between labs and have not been standardized, often resulting in only partially effective sterilization or in excessive seed mortality. Most of these methods are also not easily scalable to a large number of seed lines of diverse genotypes. As technologies for high-throughput analysis of Arabidopsis continue to proliferate, standardized techniques for sterilizing large numbers of seeds of different genotypes are becoming essential for conducting these types of experiments. The response of a number of Arabidopsis lines to two different sterilization techniques was evaluated based on seed germination rate and the level of seed contamination with microbes and other pathogens. The treatments included different concentrations of sterilizing agents and times of exposure, combined to determine optimal conditions for Arabidopsis seed sterilization. Optimized protocols have been developed for two different sterilization methods: bleach (liquid-phase) and chlorine (Cl2) gas (vapor-phase), both resulting in high seed germination rates and minimal microbial contamination. The utility of these protocols was illustrated through the testing of both wild type and mutant seeds with a range of germination potentials. Our results show that seeds can be effectively sterilized using either method without excessive seed mortality, although detrimental effects of sterilization were observed for seeds with lower than optimal germination potential. In addition, an equation was developed to enable researchers to apply the standardized chlorine gas sterilization conditions to airtight containers of different sizes. The protocols described here allow easy, efficient, and

Genes encoding calmodulin-binding proteins in the Arabidopsis genome

Science.gov (United States)

Reddy, Vaka S.; Ali, Gul S.; Reddy, Anireddy S N.

2002-01-01

Analysis of the recently completed Arabidopsis genome sequence indicates that approximately 31% of the predicted genes could not be assigned to functional categories, as they do not show any sequence similarity with proteins of known function from other organisms. Calmodulin (CaM), a ubiquitous and multifunctional Ca(2+) sensor, interacts with a wide variety of cellular proteins and modulates their activity/function in regulating diverse cellular processes. However, the primary amino acid sequence of the CaM-binding domain in different CaM-binding proteins (CBPs) is not conserved. One way to identify most of the CBPs in the Arabidopsis genome is by protein-protein interaction-based screening of expression libraries with CaM. Here, using a mixture of radiolabeled CaM isoforms from Arabidopsis, we screened several expression libraries prepared from flower meristem, seedlings, or tissues treated with hormones, an elicitor, or a pathogen. Sequence analysis of 77 positive clones that interact with CaM in a Ca(2+)-dependent manner revealed 20 CBPs, including 14 previously unknown CBPs. In addition, by searching the Arabidopsis genome sequence with the newly identified and known plant or animal CBPs, we identified a total of 27 CBPs. Among these, 16 CBPs are represented by families with 2-20 members in each family. Gene expression analysis revealed that CBPs and CBP paralogs are expressed differentially. Our data suggest that Arabidopsis has a large number of CBPs including several plant-specific ones. Although CaM is highly conserved between plants and animals, only a few CBPs are common to both plants and animals. Analysis of Arabidopsis CBPs revealed the presence of a variety of interesting domains. Our analyses identified several hypothetical proteins in the Arabidopsis genome as CaM targets, suggesting their involvement in Ca(2+)-mediated signaling networks.

A Severe Case of Pigmentary Glaucoma in a Child With a Family History of Pigment Dispersion Syndrome.

Science.gov (United States)

Aragno, Vittoria; Zeboulon, Pierre; Baudouin, Christophe; Labbé, Antoine

2016-08-01

To report a case of severe pigmentary glaucoma (PG) in a 13-year-old boy of a family affected by pigment dispersion syndrome (PDS). A 13-year-old child was referred to our hospital for severe bilateral glaucoma. A complete ophthalmologic evaluation including refraction, intraocular pressure, central corneal thickness, slit-lamp biomicroscopy, gonioscopy, fundus examination, and ultrasound biomicroscopy was performed. Family members were also examined and a family pedigree was obtained. Ophthalmologic examination revealed a severe bilateral PG with Krukenberg spindle and a widely open heavily pigmented iridocorneal angle. Ultrasound biomicroscopy showed a deep anterior chamber with pronounced iris concavity in both eyes. Within his family, his 15-year-old sister and 7-year-old brother were both affected by PDS diagnosed on gonioscopy findings. We report for the first time a severe case of pediatric PG with a family history of PDS. This case demonstrates that accurate screening is necessary in cases of familial PDS and PG, even in the pediatric population.

[Analysis of pigments from Rhodotorula glutinis by Raman spectroscopy and thin layer chromatography].

Science.gov (United States)

Yuan, Yu-feng; Tao, Zhan-hua; Wang, Xue; Li, Yong-qing; Liu, Jun-xian

2012-03-01

The pigments from Rhodotorula glutinis were separated by using thin layer chromatography, and the result showed that Rhodotorula glutinis cells could synthesize at least three kinds of pigments, which were beta-carotene, torulene, and torularhodin. The Raman spectra based on the three pigments were acquired, and original spectra were preprocessed by background elimination, baseline correction, and three-point-smoothing, then the averaged spectra from different pigments were investigated, and the result indicated that Raman shift which represents C-C bond was different, and the wave number of beta-carotene demonstrated the largest deviation, finally torulene and torularhodin in Rhodotorula glutinis had more content than beta-carotene. Quantitative analysis of Raman peak height ratio revealed that peak height ratio of pigments showed little difference, which could be used as parameters for further research on living cells, providing reference content of pigments. The above results suggest that Raman spectroscopy combined with thin layer chromatography can be applied to analyze pigments from Rhodotorula glutinis, provides abundant information about pigments, and serves as an effective method to study pigments.

Prodigiosin pigment of Serratia marcescens is associated with increased biomass production.

Science.gov (United States)

Haddix, Pryce L; Shanks, Robert M Q

2018-04-03

Serratia marcescens is a gram-negative, facultatively-anaerobic bacterium and opportunistic pathogen which produces the red pigment prodigiosin. We employed both batch culture and chemostat growth methods to investigate prodigiosin function in the producing organism. Pigmentation correlated with an increased rate of ATP production during population lag phase. Results with a lacZ transcriptional fusion to the prodigiosin (pig) biosynthetic operon revealed that operon transcription is activated by low cellular levels of ATP at high cell density. Furthermore, these data enabled estimation of the ATP per cell minimum value at which the operon is induced. Pigmented cells were found to accumulate ATP more rapidly and to multiply more quickly than non-pigmented cells during the high density growth phase. Finally, results with both batch and chemostat culture revealed that pigmented cells grow to approximately twice the biomass yield as non-pigmented S. marcescens bacteria. Prodigiosin production may, therefore, provide a growth advantage at ambient temperatures.

Current perspective of yellowish-orange pigments from microorganisms- a review

OpenAIRE

Aruldass , Claira Arul; Dufossé , Laurent; Ahmad , Wan Azlina

2018-01-01

International audience; Natural yellowish-orange pigments are derived from bacteria, yeasts, fungi and microalgae, including Chryseobacterium, Monascus and Chlorella. The purpose of this review is to provide an overview of these pigments in various aspects towards exploiting them for numerous functions. These pigments are produced in various shades of yellow-orange and categorised as carotenoids, anthraquinones, zeaxanthin, flexirubin and other compounds. They served as alternative colourants...

Production of colourful pigments consisting of amorphous arrays of silica particles.

Science.gov (United States)

Yoshioka, Shinya; Takeoka, Yukikazu

2014-08-04

It is desirable to produce colourful pigments that have anti-fading properties and are environmentally friendly. In this Concept, we describe recently developed pigments that exhibit such characteristics. The pigments consist of amorphous arrays of submicron silica particles, and they exhibit saturated and angle-independent structural colours. Variously coloured pigments can be produced by changing the size of the particles, and the saturation of the colour can be controlled by incorporating small amounts of black particles. We review a simple analysis that is useful for interpreting the angular independence of the structural colours and discuss the remaining tasks that must be accomplished for the realistic application of these pigments. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Raman af hvide pigmenter

DEFF Research Database (Denmark)

Reeler, Nini Elisabeth Abildgaard; Nielsen, Ole Faurskov; Sauer, Stephan P. A.

2013-01-01

Et samspil mellem kunst og kemi. I et samarbejde mellem Statens Museum for Kunst og Kemisk Institut på KU er Ramanspek-troskopi brugt til at definere sammensætningen af blandinger af blyhvidt og calcit i maleriers hvide pigmenter....

Ultrastructural analysis of the pigment dispersion syndrome in DBA/2J mice.

Science.gov (United States)

Schraermeyer, Mareike; Schnichels, Sven; Julien, Sylvie; Heiduschka, Peter; Bartz-Schmidt, Karl-Ulrich; Schraermeyer, Ulrich

2009-11-01

To characterise ocular pigment abnormalities associated with iris atrophy in DBA/2J mice as a model for human pigment dispersion syndrome. Immunohistochemistry, electron and light microscopy were performed to examine the eyes of DBA/2J mice ranging in age from 2.5 to 18 months old. The focus of our study was the description of the ultrastructural modifications in the irides of DBA/2J mice. The DBA/2J mice presented modifications in the melanosomes in all the pigmented parts of the eye, including the retinal pigment epithelial cells and choroidal melanocytes of the ciliary pigment epithelium. The extracellular matrix of the iris stroma disappeared with ageing. Pigmented cells detached from the iris and migrated into the trabecular meshwork exclusively on the anterior iris surface. These cells were identified as macrophages by immunohistochemistry and electron microscopy. There was no evidence that melanocytes or iris pigment epithelial cells migrated into the trabecular meshwork, but they became more and more depigmented. The aqueous outflow was blocked by pigment-laden cells, but not by cellular debris or melanosomes. No substantial amount of extracellular melanosomes was observed. The morphology of melanosomes is aberrant in all pigment cells in the eyes of DBA/2J mice. We conclude that the disease process begins with the transfer of both immature melanosomes from the iris pigment epithelium (IPE) and melanocytes to macrophages, which subsequently migrate into the trabecular meshwork. Accumulating macrophages cause a blockade of the chamber angle. As the disease progresses, the IPE, melanocytes and iris stroma, including blood vessels, disappear, leading to iris atrophy. It is speculated that the loss of these pigment cells is partly caused by reduction of the iris stroma.

A Lipid Transfer Protein Increases the Glutathione Content and Enhances Arabidopsis Resistance to a Trichothecene Mycotoxin.

Directory of Open Access Journals (Sweden)

John E McLaughlin

Full Text Available Fusarium head blight (FHB or scab is one of the most important plant diseases worldwide, affecting wheat, barley and other small grains. Trichothecene mycotoxins such as deoxynivalenol (DON accumulate in the grain, presenting a food safety risk and health hazard to humans and animals. Despite considerable breeding efforts, highly resistant wheat or barley cultivars are not available. We screened an activation tagged Arabidopsis thaliana population for resistance to trichothecin (Tcin, a type B trichothecene in the same class as DON. Here we show that one of the resistant lines identified, trichothecene resistant 1 (trr1 contains a T-DNA insertion upstream of two nonspecific lipid transfer protein (nsLTP genes, AtLTP4.4 and AtLTP4.5. Expression of both nsLTP genes was induced in trr1 over 10-fold relative to wild type. Overexpression of AtLTP4.4 provided greater resistance to Tcin than AtLTP4.5 in Arabidopsis thaliana and in Saccharomyces cerevisiae relative to wild type or vector transformed lines, suggesting a conserved protection mechanism. Tcin treatment increased reactive oxygen species (ROS production in Arabidopsis and ROS stain was associated with the chloroplast, the cell wall and the apoplast. ROS levels were attenuated in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls. Exogenous addition of glutathione and other antioxidants enhanced resistance of Arabidopsis to Tcin while the addition of buthionine sulfoximine, an inhibitor of glutathione synthesis, increased sensitivity, suggesting that resistance was mediated by glutathione. Total glutathione content was significantly higher in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls, highlighting the importance of AtLTP4.4 in maintaining the redox state. These results demonstrate that trichothecenes cause ROS accumulation and overexpression of AtLTP4.4 protects against trichothecene-induced oxidative stress by increasing the glutathione

Strong Impact of an Axial Ligand on the Absorption by Chlorophyll a and b Pigments Determined by Gas-Phase Ion Spectroscopy Experiments

DEFF Research Database (Denmark)

Kjaer, Christina; Stockett, Mark H.; Pedersen, Bjarke Møller

2016-01-01

The microenvironments in photosynthetic proteins affect the absorption by chlorophyll (Chl) pigments. It is, however, a challenge to disentangle the impact on the transition energies of different perturbations, for example, the global electrostatics of the protein (nonbonded environmental effects......), exciton coupling between Chl's, conformational variations, and binding of an axial ligand to the magnesium center. This is needed to distinguish between the two most commonly proposed mechanisms for energy transport in photosynthetic proteins, relying on either weakly or strongly coupled pigments. Here...

Retrospective Evaluation of Topical Bimatoprost and Iris Pigmentation Change.

Science.gov (United States)

Zaleski-Larsen, Lisa A; Ruth, Nadine H; Fabi, Sabrina G

2017-12-01

Topical bimatoprost is a topical prostaglandin analog originally used to treat glaucoma and more recently used to cosmetically induce hypertrichosis of the eyelashes. Iris pigmentation change has been noted in the treatment of glaucoma but has not been assessed with the cosmetic periorbital application of bimatoprost. To evaluate for iris pigmentation change with the long-term cosmetic use of topical bimatoprost. A retrospective chart review in a cosmetic dermatology practice of women (N = 50) who consistently purchased topical bimatoprost over an average of 4.59 years was compared with that of age-matched non-bimatoprost patients (N = 50). A blinded evaluator assessed each patient for iris pigmentary change. No iris pigmentation change was noted with the cutaneous application of bimatoprost. The cutaneous application of bimatoprost appears to be safe with minimal risk for iris pigmentation change.

Ultraviolet radiation effects on pigmentation in the cyanobacterium ''Phormidium uncinatum''

International Nuclear Information System (INIS)

Donkor, V.A.; Haeder, D.P.

1997-01-01

The Baikal strain of the cyanobacterium Phormidium uncinatum was found to possess the photosynthetic pigments chlorophyll a, carotenoids, phycocyanin and allophycocyanin, while the Tuebingen strain of Phormidium contained, in addition to these, the biliprotein phycoerythrin. Sucrose gradient centrifugation of the pigment extracts resulted in a separation of the phycobiliproteins into several bands, which according to their absorption and fluorescence properties, were identified as monomers, trimers and hexamers. With increasing UV-B irradiation the heavier aggregates were broken down into smaller components. Photobleaching of these accessory pigments also occurred. FPLC gel filtration analyses of the pigments also showed loss of heavier aggregates of the phycobilins and bleaching of the pigments. SDS-polyacrylamide gel electrophoresis of the sucrose gradient and FPLC fractions indicated loss of the biliproteins with increasing UV-B irradiation. The loss of the β- were more rapid than that of the α- subunits. Increasing levels of ultraviolet irradiation is therefore deleterious to these organism. (author)

Properties of alginate fiber spun-dyed with fluorescent pigment dispersion.

Science.gov (United States)

Wang, Ping; Tawiah, Benjamin; Tian, Anli; Wang, Chunxia; Zhang, Liping; Fu, Shaohai

2015-03-15

Spun-dyed alginate fiber was prepared by the spun-dyeing method with the mixture of fluorescent pigment dispersion and sodium alginate fiber spinning solution, and its properties were characterized by SEM, TGA, DSC, and XRD. The results indicate that fluorescent pigment dispersion prepared with esterified poly (styrene-alt maleic acid) had excellent compatibility with sodium alginate fiber spinning solution, and small amount of fluorescent pigment could reduce the viscosity of spun-dyed spinning solutions. SEM photo of spun-dyed alginate fiber indicated that fewer pigment particles deposited on its surface. TGA, DSC, and XRD results suggested that thermal properties and crystal phase of spun-dyed alginate fibers had slight changes compared to the original alginate fibers. The fluorescence intensity of spun-dyed alginate fiber reached its maximum when the content of fluorescent pigment was 4%. The spun-dyed alginate fiber showed excellent rubbing and washing fastness. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis and Characterization of a New Heterocyclic Azo Pigment

International Nuclear Information System (INIS)

Asniza, M.; Issam, A.M.; Khalil, H.P.S.A.

2011-01-01

A new heterocyclic coupling agent has been produced from the reaction of maleic anhydride and p-aminophenol, namely N-(4-hexahydrophenol)maleimide. The coupling agent underwent azo coupling reaction with aromatic amine, which is p-aminophenol to produce a new heterocyclic azo pigment. The pigment was then subjected to solubility, hiding power and light fastness test. Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet/ Visible (UV/Vis) Spectroscopy, and Nuclear Magnetic Resonance Spectroscopy ( 1 H-NMR, 13 C-NMR) were used to obtain the characteristics and structural features of the pigment. (author)

Genetic and Phenotypic Analysis of Lateral Root Development in Arabidopsis thaliana.

Science.gov (United States)

Napsucialy-Mendivil, Selene; Dubrovsky, Joseph G

2018-01-01

Root system formation to a great extent depends on lateral root (LR) formation. In Arabidopsis thaliana, LRs are initiated within a parent root in pericycle that is an external tissue of the stele. LR initiation takes place in a strictly acropetal pattern, whereas posterior lateral root primordium (LRP) formation is asynchronous. In this chapter, we focus on methods of genetic and phenotypic analysis of LR initiation, LRP morphogenesis, and LR emergence in Arabidopsis. We provide details on how to make cleared root preparations and how to identify the LRP stages. We also pay attention to the categorization of the LRP developmental stages and their variations and to the normalization of the number of LRs and LRPs formed, per length of the primary root, and per number of cells produced within a root. Hormonal misbalances and mutations affect LRP morphogenesis significantly, and the evaluation of LRP abnormalities is addressed as well. Finally, we deal with various molecular markers that can be used for genetic and phenotypic analyses of LR development.

Proteomic and phosphoproteomic analyses of chromatin-associated proteins from Arabidopsis thaliana

KAUST Repository

Bigeard, Jean

2014-07-10

The nucleus is the organelle where basically all DNA-related processes take place in eukaryotes, such as replication, transcription, and splicing as well as epigenetic regulation. The identification and description of the nuclear proteins is one of the requisites toward a comprehensive understanding of the biological functions accomplished in the nucleus. Many of the regulatory mechanisms of protein functions rely on their PTMs among which phosphorylation is probably one of the most important properties affecting enzymatic activity, interaction with other molecules, localization, or stability. So far, the nuclear and subnuclear proteome and phosphoproteome of the model plant Arabidopsis thaliana have been the subject of very few studies. In this work, we developed a purification protocol of Arabidopsis chromatin-associated proteins and performed proteomic and phosphoproteomic analyses identifying a total of 879 proteins of which 198 were phosphoproteins that were mainly involved in chromatin remodeling, transcriptional regulation, and RNA processing. From 230 precisely localized phosphorylation sites (phosphosites), 52 correspond to hitherto unidentified sites. This protocol and data thereby obtained should be a valuable resource for many domains of plant research.

FIN5 positively regulates far-red light responses in Arabidopsis thaliana

International Nuclear Information System (INIS)

Cho, D.S.; Hong, S.H.; Nam, H.G.; Soh, M.S.

2003-01-01

We report the characterization of a semi-dominant mutation fin5-1 (far-red insensitive 5-1) of Arabidopsis, which was isolated from genetic screening of phytochrome A (phyA) signaling components. Plants with the fin5-1 mutation exhibited a long hypocotyl phenotype when grown under far-red (FR) light, but not under red light. Physiological analyses implied that FIN5 might be differentially involved in diverse responses that are regulated by phyA under continuous FR light. Anthocyanin accumulation, gravitropic response of hypocotyl growth, and FR light-preconditioned blocking of greening were also impaired in the fin5-1 mutant, whereas photoperiodic floral induction was not, if at all, significantly affected. Moreover, light-regulated expression of the CHS, PORA and PsbS genes was attenuated in fin5-1 mutant plants, while the light-induced expression of CAB was normal. The mutation exhibited semi-dominance regarding control of hypocotyl growth in FR light. We suggest that FIN5 defines a novel branch in the network of phyA signaling in Arabidopsis. (author)

Proteomic and phosphoproteomic analyses of chromatin-associated proteins from Arabidopsis thaliana

KAUST Repository

Bigeard, Jean; Rayapuram, Naganand; Bonhomme, Ludovic; Hirt, Heribert; Pflieger, Delphine

2014-01-01

The nucleus is the organelle where basically all DNA-related processes take place in eukaryotes, such as replication, transcription, and splicing as well as epigenetic regulation. The identification and description of the nuclear proteins is one of the requisites toward a comprehensive understanding of the biological functions accomplished in the nucleus. Many of the regulatory mechanisms of protein functions rely on their PTMs among which phosphorylation is probably one of the most important properties affecting enzymatic activity, interaction with other molecules, localization, or stability. So far, the nuclear and subnuclear proteome and phosphoproteome of the model plant Arabidopsis thaliana have been the subject of very few studies. In this work, we developed a purification protocol of Arabidopsis chromatin-associated proteins and performed proteomic and phosphoproteomic analyses identifying a total of 879 proteins of which 198 were phosphoproteins that were mainly involved in chromatin remodeling, transcriptional regulation, and RNA processing. From 230 precisely localized phosphorylation sites (phosphosites), 52 correspond to hitherto unidentified sites. This protocol and data thereby obtained should be a valuable resource for many domains of plant research.

AtNPF2.5 Modulates Chloride (Cl−) Efflux from Roots of Arabidopsis thaliana

KAUST Repository

Li, Bo

2017-01-05

The accumulation of high concentrations of chloride (Cl) in leaves can adversely affect plant growth. When comparing different varieties of the same Cl sensitive plant species those that exclude relatively more Cl from their shoots tend to perform better under saline conditions; however, the molecular mechanisms involved in maintaining low shoot Cl remain largely undefined. Recently, it was shown that the NRT1/PTR Family 2.4 protein (NPF2.4) loads Cl into the root xylem, which affects the accumulation of Cl in Arabidopsis shoots. Here we characterize NPF2.5, which is the closest homolog to NPF2.4 sharing 83.2% identity at the amino acid level. NPF2.5 is predominantly expressed in root cortical cells and its transcription is induced by salt. Functional characterisation of NPF2.5 via its heterologous expression in yeast (Saccharomyces cerevisiae) and Xenopus laevis oocytes indicated that NPF2.5 is likely to encode a Cl permeable transporter. Arabidopsis npf2.5 T-DNA knockout mutant plants exhibited a significantly lower Cl efflux from roots, and a greater Cl accumulation in shoots compared to salt-treated Col-0 wild-type plants. At the same time, NO- content in 3 the shoot remained unaffected. Accumulation of Cl in the shoot increased following (1) amiRNA-induced knockdown of NPF2.5 transcript abundance in the root, and (2) constitutive over-expression of NPF2.5. We suggest that both these findings are consistent with a role for NPF2.5 in modulating Cl transport. Based on these results, we propose that NPF2.5 functions as a pathway for Cl efflux from the root, contributing to exclusion of Cl from the shoot of Arabidopsis.

Loss of CDKC;2 increases both cell division and drought tolerance in Arabidopsis thaliana.

Science.gov (United States)

Zhao, Lina; Li, Yaqiong; Xie, Qi; Wu, Yaorong

2017-09-01

Drought stress is one of the abiotic stresses that limit plant growth and agricultural productivity. To further understand the mechanism of drought tolerance and identify the genes involved in this process, a genetic screen for altered drought response was conducted in Arabidopsis. One mutant with enhanced drought tolerance was isolated and named Arabidopsis drought tolerance mutant 1 (atdtm1), which has larger lateral organs, prolonged growth duration, increased relative water content and a reduced leaf stomatal density compared with the wild type. The loss of AtDTM1 increases cell division during leaf development. The phenotype is caused by the loss of a T-DNA tagged gene encoding CYCLIN-DEPENDENT KINASE C;2 (CDKC;2), which functions in the regulation of transcription by influencing the phosphorylation status of RNA polymerase II (Pol II). Here, we show that CDKC;2 affects the transcription of downstream genes such as cell cycle genes and genes involved in stomatal development, resulting in altered plant organ size as well as drought tolerance of the plant. These results reveal the crucial role of CDKC;2 in modulating both cell division and the drought response in Arabidopsis. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

Abnormal pigmentation within cutaneous scars: A complication of wound healing

Directory of Open Access Journals (Sweden)

Sarah Chadwick

2012-01-01

Full Text Available Abnormally pigmented scars are an undesirable consequence of cutaneous wound healing and are a complication every single individual worldwide is at risk of. They present a challenge for clinicians, as there are currently no definitive treatment options available, and render scars much more noticeable making them highly distressing for patients. Despite extensive research into both wound healing and the pigment cell, there remains a scarcity of knowledge surrounding the repigmentation of cutaneous scars. Pigment production is complex and under the control of many extrinsic and intrinsic factors and patterns of scar repigmentation are unpredictable. This article gives an overview of human skin pigmentation, repigmentation following wounding and current treatment options.

Pigment dispersion syndrome associated with optic nerve melanocytoma.

Science.gov (United States)

Asorey-García, A; Méndez-Hernández, C D; Santos-Bueso, E; García-Feijoo, J

2015-10-01

A 60-year old patient was referred for cataract surgery. The examination showed retrokeratic pigment in the left eye, which had an intraocular pressure of 24 mm Hg. The funduscopy showed a brown lesion on the left optic disk, with adjacent vitreous seeding of pigment. The patient was thus diagnosed with secondary pigment dispersion syndrome due to optic disk melanocytoma. Although melanocytoma is most commonly a benign, stationary tumor, it may present with major complications leading to significant visual loss. A patient with melanocytoma of the optic disk should be examined periodically. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Bio production of red pigment by local isolate of Monascus purpureus

International Nuclear Information System (INIS)

Youssef, B.M.; Khalaf, M.A.; Emam, D.A.; Hazaa, M.M.; Shash, S.M.

2009-01-01

There is an increased interest on natural pigments to replace some currently used synthetic dyes, since the latter have been associated with toxic effects in foods. The red pigment of the fungus Monascus is widely used in all the world as food additives or pharmaceuticals. The Monascus purpureus local strain, which was isolated from dried silage sample was employed for red pigment production in submerged fermentation (Sm F) conditions. Different fermentation parameters including: incubation period, temperature, initial ph of the medium, agitation, different carbon and nitrogen sources, bio elements and type of inoculum and its age; were carried out under Sm F conditions to enhance the red pigment production. The maximum red pigment production (1.27 gI -1 ) was achieved at incubation temperature 30 C, initial ph 5.5, agitation rate 150 rpm, 2% starch and 0.4% ammonium sulphate as carbon and nitrogen sources, respectively, after 4 days when the production medium inoculated with 12 h age from seed culture inoculum. An experiment was conducted to investigate the effect of gamma irradiation on the activity of Monascus purpureus towards red pigment production. The maximum red pigment production (I.9 gI -1 ) was obtained at 0.5 kGy dose level

Dissecting historical changes of selective pressures in the evolution of human pigmentation

OpenAIRE

Huang, Xin; Wang, Sijia; Jin, Li; He, Yungang

2018-01-01

Human pigmentation is a highly diverse trait among populations, and has drawn particular attention from both academic and non-academic investigators for thousands of years. To explain the diversity of human pigmentation, researchers have proposed that human pigmentation is adapted for ultraviolet radiation and driven by natural selection. Although studies have detected signals of natural selection in several human pigmentation genes, none have quantitatively investigated the historical select...

Induction and characterization of Arabidopsis mutants by Ion beam

International Nuclear Information System (INIS)

Yoon, Y. H.; Choi, J. D.; Park, J. Y.; Lee, J. R.; Sohn, H. S.

2008-03-01

This study was conducted to search the proper conditions and times for irradiating proton beam to seeds generally used for induction of mutant. Arabidopsis as model plants has good characters that is a short generation time, producing a lot of seeds, sequenced genome, developed maker. This points were the best materials for plant breeding for this study. The data of inducing mutants of Arabidopsis is used to be applicate to crops have more longer generation that is the final goals of this study. The goals of this project were to inducing and characterizing arabidopsis mutants by the proton ion beam and γ-ray. As well as, the purpose of this study was securing more than 10 lines of arabidopsis mutants in this project and also to know the changed DNA structure of the mutants using the basic data for applying to the more study

Induction and characterization of Arabidopsis mutants by Ion beam

Energy Technology Data Exchange (ETDEWEB)

Yoon, Y. H.; Choi, J. D.; Park, J. Y.; Lee, J. R.; Sohn, H. S. [Gyeongbuk Institute for Bio Industry, Andong (Korea, Republic of)

2008-03-15

This study was conducted to search the proper conditions and times for irradiating proton beam to seeds generally used for induction of mutant. Arabidopsis as model plants has good characters that is a short generation time, producing a lot of seeds, sequenced genome, developed maker. This points were the best materials for plant breeding for this study. The data of inducing mutants of Arabidopsis is used to be applicate to crops have more longer generation that is the final goals of this study. The goals of this project were to inducing and characterizing arabidopsis mutants by the proton ion beam and {gamma}-ray. As well as, the purpose of this study was securing more than 10 lines of arabidopsis mutants in this project and also to know the changed DNA structure of the mutants using the basic data for applying to the more study

Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens

Directory of Open Access Journals (Sweden)

Vikas Veerwal

2017-01-01

Full Text Available Pigment dispersion syndrome (PDS is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens.

Science.gov (United States)

Veerwal, Vikas; Goyal, Jawahar Lal; Jain, Parul; Arora, Ritu

2017-01-01

Pigment dispersion syndrome (PDS) is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA) of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

Glufosinate ammonium selection of transformed Arabidopsis.

Science.gov (United States)

Weigel, Detlef; Glazebrook, Jane

2006-12-01

INTRODUCTIONOne of the most commonly used markers for the selection of transgenic Arabidopsis is resistance to glufosinate ammonium, an herbicide that is sold under a variety of trade names including Basta and Finale. Resistance to glufosinate ammonium is conferred by the bacterial bialophos resistance gene (BAR) encoding the enzyme phosphinotricin acetyl transferase (PAT). This protocol describes the use of glufosinate ammonium to select transformed Arabidopsis plants. The major advantage of glufosinate ammonium selection is that it can be performed on plants growing in soil and does not require the use of sterile techniques.

Members of the LBD Family of Transcription Factors Repress Anthocyanin Synthesis and Affect Additional Nitrogen Responses in Arabidopsis

OpenAIRE

Rubin, G.; Tohge, T.; Matsuda, F.; Saito, K.; Scheible, W.

2009-01-01

Nitrogen (N) and nitrate (NO3-) per se regulate many aspects of plant metabolism, growth, and development. N/NO3- also suppresses parts of secondary metabolism, including anthocyanin synthesis. Molecular components for this repression are unknown. We report that three N/NO3--induced members of the LATERAL ORGAN BOUNDARY DOMAIN (LBD) gene family of transcription factors (LBD37, LBD38, and LBD39) act as negative regulators of anthocyanin biosynthesis in Arabidopsis thaliana. Overexpression of e...

The 'push-pull' dosimeter: When two pigments are better than one

International Nuclear Information System (INIS)

Bosi, Stephen G; Baldock, Clive; Smee, Robert

2010-01-01

A new kind of gel dosimeter (the 'push-pull' dosimeter) is proposed which would contain two spectrally complementary pigments, one which darkens with increasing dose and another which bleaches. The bleaching pigment would be optimised for high sensitivity and the darkening pigment for low sensitivity. By employing dual pigments optimised independently, the usual requisite compromises between sensitivity at low dose and accuracy at high dose would be relaxed. Such a gel, after exposure would be read using two successive optical CT scans employing two different scan wavelengths. The use of dual pigments could also reduce the occurrence of regions of high optical attenuation which generate artefacts in optical CT. This paper also presents results of simulations of the behaviour of such a gel when scanned using optical cone beam CT.

Glucose, fructose and sucrose increase the solubility of protein-tannin complexes and at high concentration, glucose and sucrose interfere with bisulphite bleaching of wine pigments.

Science.gov (United States)

Harbertson, James F; Yuan, Chunlong; Mireles, Maria S; Hanlin, Rachel L; Downey, Mark O

2013-05-01

Wines were modified with increasing sugar concentrations and decreasing tannin concentrations and analysed by a combination of protein precipitation and bisulphite bleaching. Increasing sugar concentration decreased the precipitation of tannin and protein-precipitable polymeric pigments (PPP). The use of a hydrogen bond disruptor (urea) to reduce protein-tannin and protein-pigment complex formation showed that the effect of sugar concentration occurred by increasing the solubility of the tannin-protein complex, not by interfering with protein-tannin complex formation. By increasing the solubility of pigment-protein complexes, non-protein-precipitable polymeric pigments (nPPP) appeared to increase. There was also an increase in total polymeric pigments at each tannin concentration with increasing glucose and sucrose concentration, indicating that sugar concentration might also affect bisulphite bleaching of wine pigments. While a significant effect of sugar concentration on tannin-protein complex solubility was observed, these effects were greatest at sugar concentrations far in excess of normal wine making conditions. Under normal wine making conditions, sugar concentration will have a negligible effect on protein-precipitable tannin, PPP and nPPP concentrations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Novel environment friendly corrosion inhibitor pigments based on naturally occurring clay minerals

Energy Technology Data Exchange (ETDEWEB)

Bohm, S.; McMurray, H.N.; Worsley, D.A. [University of Wales, Swansea (United Kingdom). Dept. of Materials Engineering; Powell, S.M. [University of Wales, Swansea (United Kingdom). Engineering Doktorate Centre

2001-12-01

Novel, ceramic, corrosion inhibitor pigments consisting of cerium (III) and calcium (II) cation exchanged bentonites have been shown to provide effective cut-edge corrosion resistance in organic coated galvanised steel. The bentonite pigments were prepared from a naturally occurring (Wyoming) bentonite with a cation-exchange-capacity of 0.7 milli-equivalents per gram. Cation exchange was carried out by repeated washing with aqueous solutions of cerium (III) chloride and calcium (II) chloride to produce bentonites containing 31500 ppm exchangeable cerium (III) and 13500 ppm exchangeable calcium (II) respectively. The resulting bentonite pigments were dispersed in a polyester-resin based primer paint system to give a pigment volume concentration of 19%. For comparison, two similar primer systems were prepared containing a commercial calcium (II) exchanged silica pigment Shieldex: 60 000 ppm calcium (II) and a strontium chromate dispersion, both with a 19% pigment volume concentration. All three primer systems were applied (5 {mu}m) to the zinc surface of galvanised 0.7 mm gauge sheet steel and overcoated with an architectural polyester topcoat (18 {mu}m). The performance of the inhibitor pigments was compared by measuring the rate of corrosion-driven organic coating delamination from the cut edge of samples during 1000 h of salt-spray testing. The calcium (II) bentonite pigment exhibited an anti-delamination performance similar to that of strontium chromate but superior to that of Shieldex. However, the cerium (III) bentonite pigment was superior in performance to both strontium chromate and Shieldex. Thus, the bentonite pigments represent promising, environmentally friendly, ion-exchange corrosion inhibitors which exhibit good anti-delamination performance by comparison with current commercial systems. (orig.)

Synthesis and characterization of hematite pigment obtained from a steel waste industry

Energy Technology Data Exchange (ETDEWEB)

Prim, S.R. [Department of Mechanical Engineering, University of the State of Santa Catarina, Santa Catarina (Brazil); Folgueras, M.V., E-mail: dem2mvf@joinville.udesc.br [Department of Mechanical Engineering, University of the State of Santa Catarina, Santa Catarina (Brazil); Lima, M.A. de [Department of Mechanical Engineering, University of the State of Santa Catarina, Santa Catarina (Brazil); Hotza, D. [Departamento de Engenharia Quimica, Federal University of Santa Catarina, Santa Catarina (Brazil)

2011-09-15

Highlights: {yields} The study of using of a industrial waste for the synthesis of hematite pigments. {yields} The nanometer dimension this waste and your behavior as chromophore. {yields} The effect of process variables on the mechanisms of encapsulation sintered pigments. - Abstract: Pigments that meet environmental and technology requirements are the focus of the research in the ceramic sector. This study focuses on the synthesis of ceramic pigment by encapsulation of hematite in crystalline and amorphous silica matrix. Iron oxide from a metal sheet rolling process was used as chromophore. A different content of hematite and silica was homogenized by conventional and high energy milling. The powders obtained after calcinations between 1050 and 1200 {sup o}C for 2 h were characterized by X-ray diffraction and SEM analysis. The pigments were applied to ceramic enamel and porcelain body. The effect of pigment was measured by comparing L*a*b* values of the heated samples. Results showed that the color developed is influenced by variables such as oxide content employed, conditions of milling and processing temperature. The results showed that the use of pigment developed does not interfere in microstructural characteristics of pigmented material. The best hue was obtained from samples with 15 wt% of chromophore, heated at 1200 {sup o}C in amorphous silica matrix.

The red pigment prodigiosin is not an essential virulence factor in entomopathogenic Serratia marcescens.

Science.gov (United States)

Zhou, Wei; Li, JingHua; Chen, Jie; Liu, XiaoYuan; Xiang, TingTing; Zhang, Lin; Wan, YongJi

2016-05-01

Although pigments produced by pathogenic microbes are generally hypothesized as essential virulence factors, the role of red pigment prodigiosin in the pathogenesis of entomopathogenic Serratia marcescens is not clear. In this study, we analyzed the pathogenicity of different pigmented S. marcescens strains and their non-pigmented mutants in silkworms. Each pigmented strain and the corresponding non-pigmented mutants showed very similar LD50 value (statistically no difference), but caused very different symptom (color of the dead larva). Our results clearly indicated that the red pigment prodigiosin is not an essential virulence factor in entomopathogenic S. marcescens. Copyright © 2016 Elsevier Inc. All rights reserved.

Visual pigments in a living fossil, the Australian lungfish Neoceratodus forsteri

Directory of Open Access Journals (Sweden)

Davies Wayne L

2007-10-01

Full Text Available Abstract Background One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. Results Here we identify and characterise five visual pigments (rh1, rh2, lws, sws1 and sws2 expressed in the retina of N. forsteri. Phylogenetic analysis of the molecular evolution of lungfish and other vertebrate visual pigment genes indicates a closer relationship between lungfish and amphibian pigments than to pigments in teleost fishes. However, the relationship between lungfish, the coelacanth and tetrapods could not be absolutely determined from opsin phylogeny, supporting an unresolved trichotomy between the three groups. Conclusion The presence of four cone pigments in Australian lungfish suggests that the earliest tetrapods would have had a colorful view of their terrestrial environment.

Visual pigments in a living fossil, the Australian lungfish Neoceratodus forsteri.

Science.gov (United States)

Bailes, Helena J; Davies, Wayne L; Trezise, Ann E O; Collin, Shaun P

2007-10-25

One of the greatest challenges facing the early land vertebrates was the need to effectively interpret a terrestrial environment. Interpretation was based on ocular adaptations evolved for an aquatic environment millions of years earlier. The Australian lungfish Neoceratodus forsteri is thought to be the closest living relative to the first terrestrial vertebrate, and yet nothing is known about the visual pigments present in lungfish or the early tetrapods. Here we identify and characterise five visual pigments (rh1, rh2, lws, sws1 and sws2) expressed in the retina of N. forsteri. Phylogenetic analysis of the molecular evolution of lungfish and other vertebrate visual pigment genes indicates a closer relationship between lungfish and amphibian pigments than to pigments in teleost fishes. However, the relationship between lungfish, the coelacanth and tetrapods could not be absolutely determined from opsin phylogeny, supporting an unresolved trichotomy between the three groups. The presence of four cone pigments in Australian lungfish suggests that the earliest tetrapods would have had a colorful view of their terrestrial environment.

Marennine, Promising Blue Pigments from a Widespread Haslea Diatom Species Complex

Directory of Open Access Journals (Sweden)

Romain Gastineau

2014-05-01

Full Text Available In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries.

Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes.

Science.gov (United States)

Riechmann, J L; Heard, J; Martin, G; Reuber, L; Jiang, C; Keddie, J; Adam, L; Pineda, O; Ratcliffe, O J; Samaha, R R; Creelman, R; Pilgrim, M; Broun, P; Zhang, J Z; Ghandehari, D; Sherman, B K; Yu, G

2000-12-15

The completion of the Arabidopsis thaliana genome sequence allows a comparative analysis of transcriptional regulators across the three eukaryotic kingdoms. Arabidopsis dedicates over 5% of its genome to code for more than 1500 transcription factors, about 45% of which are from families specific to plants. Arabidopsis transcription factors that belong to families common to all eukaryotes do not share significant similarity with those of the other kingdoms beyond the conserved DNA binding domains, many of which have been arranged in combinations specific to each lineage. The genome-wide comparison reveals the evolutionary generation of diversity in the regulation of transcription.

Accumulation and phytotoxicity of perfluorooctanoic acid in the model plant species Arabidopsis thaliana

International Nuclear Information System (INIS)

Yang, Xinping; Ye, Chengchen; Liu, Yu; Zhao, Fang-Jie

2015-01-01

Perfluorooctanoic acid (PFOA) is widely used in the manufacture of many industrial and household products. To assess the potential environmental risk of PFOA, its accumulation, translocation and phytotoxic effects were investigated using the model plant species Arabidopsis thaliana. Exposure to 18 μM PFOA-F in agar plates did not affect plant growth, but 181–1811 μM PFOA-F inhibited root and shoot growth. PFOA was more phytotoxic on shoot growth than NaF at the equivalent F concentration, with the latter having 3.9–7.6 times higher EC50 for shoot biomass than PFOA. PFOA was efficiently translocated from roots to shoots, where it existed as intact PFOA molecules without transformation evidenced by the 19 F NMR spectra. PFOA caused a significant increase in the concentration of H 2 O 2 and malondialdehyde (MDA) in shoots, indicating that oxidative stress is a likely cause of PFOA phytotoxicity. - Highlights: • PFOA is more phytotoxic on shoot growth than NaF at the equivalent F concentration. • PFOA is readily taken up and translocated from roots to shoots. • PFOA exists as intact molecules without transformation in Arabidopsis shoots. • PFOA causes oxidative stress in Arabidopsis shoots. - Perfluorooctanoic acid causes oxidative stress and is more phytotoxic on shoot growth than inorganic fluoride at the equivalent F concentration.

NANO-SIZED PIGMENT APPLICATIONS IN İZNİK TILES

Directory of Open Access Journals (Sweden)

Esin GÜNAY

2012-12-01

Full Text Available Traditional İznik tiles are known as “unproducable” due to its high quartz content. İznik tiles contain four different layers as “body, engobe (slip, decors and glaze” and each one has some different starting materials. Recent studies have showed that the production techniques and the particle size of pigments are important parameters in development of colours. TUBITAK MRC and İznik Foundation carried out an experimental work to improve and understand the effects of nanotechnology application to İznik tiles. High quartz content was kept as it is and pigments were applied in decorationas nano-sized pigments.İznik tiles were produced and comparison was carried out between traditional and modern İznik tiles in colour and brightness. Characterization techniques were used in order to understand andcompare the results and also the effects of nano-sized pigments to İznik tiles.

Resonant imaging of carotenoid pigments in the human retina

Science.gov (United States)

Gellermann, Werner; Emakov, Igor V.; McClane, Robert W.

2002-06-01

We have generated high spatial resolution images showing the distribution of carotenoid macular pigments in the human retina using Raman spectroscopy. A low level of macular pigments is associated with an increased risk of developing age-related macular degeneration, a leading cause of irreversible blindness. Using excised human eyecups and resonant excitation of the pigment molecules with narrow bandwidth blue light from a mercury arc lamp, we record Raman images originating from the carbon-carbon double bond stretch vibrations of lutein and zeaxanthin, the carotenoids comprising human macular pigments. Our Raman images reveal significant differences among subjects, both in regard to absolute levels as well as spatial distribution within the macula. Since the light levels used to obtain these images are well below established safety limits, this technique holds promise for developing a rapid screening diagnostic in large populations at risk for vision loss from age-related macular degeneration.

Similar Pathogen Targets in Arabidopsis thaliana and Homo sapiens Protein Networks

Science.gov (United States)

2012-09-21

Similar Pathogen Targets in Arabidopsis thaliana and Homo sapiens Protein Networks Paulo Shakarian1*, J. Kenneth Wickiser2 1 Paulo Shakarian...significantly attacked. Citation: Shakarian P, Wickiser JK (2012) Similar Pathogen Targets in Arabidopsis thaliana and Homo sapiens Protein Networks...to 00-00-2012 4. TITLE AND SUBTITLE Similar Pathogen Targets in Arabidopsis thaliana and Homo sapiens Protein Networks 5a. CONTRACT NUMBER 5b

Mass Spectrometric Analysis of Synthetic Organic Pigments.

Science.gov (United States)

Sugaya, Naeko; Takahashi, Mitsuko; Sakurai, Katsumi; Tanaka, Nobuko; Okubo, Ichiro; Kawakami, Tsuyoshi

2018-04-18

Though synthetic organic colorants are used in various applications nowadays, there is the concern that impurities by-produced during the manufacturing and degradation products in some of these colorants are persistent organic pollutants and carcinogens. Thus, it is important to identify the synthetic organic colorants in various products, such as commercial paints, ink, cosmetics, food, textile, and plastics. Dyes, which are soluble in water and other solvents, could be analyzed by chromatographic methods. In contrast, it is difficult to analyze synthetic organic pigments by these methods because of their insolubility. This review is an overview of mass spectrometric analysis of synthetic organic pigments by various ionization methods. We highlight a recent study of textile samples by atmospheric pressure solid analysis probe MS. Furthermore, the mass spectral features of synthetic organic pigments and their separation from other components such as paint media and plasticizers are discussed.

Microanalysis study of archaeological mural samples containing Maya blue pigment

International Nuclear Information System (INIS)

Sanchez del Rio, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhee, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

2004-01-01

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used

Microanalysis study of archaeological mural samples containing Maya blue pigment

Science.gov (United States)

Sánchez del Río, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhée, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

2004-10-01

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

Microanalysis study of archaeological mural samples containing Maya blue pigment

Energy Technology Data Exchange (ETDEWEB)

Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

2004-10-08

Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

Identification of the arabidopsis RAM/MOR signalling network: adding new regulatory players in plant stem cell maintenance and cell polarization

Science.gov (United States)

Zermiani, Monica; Begheldo, Maura; Nonis, Alessandro; Palme, Klaus; Mizzi, Luca; Morandini, Piero; Nonis, Alberto; Ruperti, Benedetto

2015-01-01

Background and Aims The RAM/MOR signalling network of eukaryotes is a conserved regulatory module involved in co-ordination of stem cell maintenance, cell differentiation and polarity establishment. To date, no such signalling network has been identified in plants. Methods Genes encoding the bona fide core components of the RAM/MOR pathway were identified in Arabidopsis thaliana (arabidopsis) by sequence similarity searches conducted with the known components from other species. The transcriptional network(s) of the arabidopsis RAM/MOR signalling pathway were identified by running in-depth in silico analyses for genes co-regulated with the core components. In situ hybridization was used to confirm tissue-specific expression of selected RAM/MOR genes. Key Results Co-expression data suggested that the arabidopsis RAM/MOR pathway may include genes involved in floral transition, by co-operating with chromatin remodelling and mRNA processing/post-transcriptional gene silencing factors, and genes involved in the regulation of pollen tube polar growth. The RAM/MOR pathway may act upstream of the ROP1 machinery, affecting pollen tube polar growth, based on the co-expression of its components with ROP-GEFs. In silico tissue-specific co-expression data and in situ hybridization experiments suggest that different components of the arabidopsis RAM/MOR are expressed in the shoot apical meristem and inflorescence meristem and may be involved in the fine-tuning of stem cell maintenance and cell differentiation. Conclusions The arabidopsis RAM/MOR pathway may be part of the signalling cascade that converges in pollen tube polarized growth and in fine-tuning stem cell maintenance, differentiation and organ polarity. PMID:26078466

Growth platform-dependent and -independent phenotypic and metabolic responses of Arabidopsis and its halophytic relative, Eutrema salsugineum, to salt stress.

Science.gov (United States)

Kazachkova, Yana; Batushansky, Albert; Cisneros, Aroldo; Tel-Zur, Noemi; Fait, Aaron; Barak, Simon

2013-07-01

Comparative studies of the stress-tolerant Arabidopsis (Arabidopsis thaliana) halophytic relative, Eutrema salsugineum, have proven a fruitful approach to understanding natural stress tolerance. Here, we performed comparative phenotyping of Arabidopsis and E. salsugineum vegetative development under control and salt-stress conditions, and then compared the metabolic responses of the two species on different growth platforms in a defined leaf developmental stage. Our results reveal both growth platform-dependent and -independent phenotypes and metabolic responses. Leaf emergence was affected in a similar way in both species grown in vitro but the effects observed in Arabidopsis occurred at higher salt concentrations in E. salsugineum. No differences in leaf emergence were observed on soil. A new effect of a salt-mediated reduction in E. salsugineum leaf area was unmasked. On soil, leaf area reduction in E. salsugineum was mainly due to a fall in cell number, whereas both cell number and cell size contributed to the decrease in Arabidopsis leaf area. Common growth platform-independent leaf metabolic signatures such as high raffinose and malate, and low fumarate contents that could reflect core stress tolerance mechanisms, as well as growth platform-dependent metabolic responses were identified. In particular, the in vitro growth platform led to repression of accumulation of many metabolites including sugars, sugar phosphates, and amino acids in E. salsugineum compared with the soil system where these same metabolites accumulated to higher levels in E. salsugineum than in Arabidopsis. The observation that E. salsugineum maintains salt tolerance despite growth platform-specific phenotypes and metabolic responses suggests a considerable degree of phenotypic and metabolic adaptive plasticity in this extremophile.

Auto white balance method using a pigmentation separation technique for human skin color

Science.gov (United States)

Tanaka, Satomi; Kakinuma, Akihiro; Kamijo, Naohiro; Takahashi, Hiroshi; Tsumura, Norimichi

2017-02-01

The human visual system maintains the perception of colors of an object across various light sources. Similarly, current digital cameras feature an auto white balance function, which estimates the illuminant color and corrects the color of a photograph as if the photograph was taken under a certain light source. The main subject in a photograph is often a person's face, which could be used to estimate the illuminant color. However, such estimation is adversely affected by differences in facial colors among individuals. The present paper proposes an auto white balance algorithm based on a pigmentation separation method that separates the human skin color image into the components of melanin, hemoglobin and shading. Pigment densities have a uniform property within the same race that can be calculated from the components of melanin and hemoglobin in the face. We, thus, propose a method that uses the subject's facial color in an image and is unaffected by individual differences in facial color among Japanese people.

Characteristic Elemental Composition of Oil Pigments using Instrumental Neutron Activation Analysis

International Nuclear Information System (INIS)

Chung, Yong Sam; Kim, Sun Ha; Sun, Gwang Min; Lim, Jong Myung; Moon, Jong Hwa; Kim, Young Jin; Lim, Sung Jin; Song, Yu Na; Kim, Ken

2009-01-01

The principal aim of this study is to identify the applicability of instrumental neutron activation analysis as a non-destructive examination tool for the quantitative composition analysis associated with authentication, restoration, and conservation of art objects in the field of cultural heritage. Generally, the chemical composition of pigments are associated with the colors such as white, yellow, orange, red, green, blue and black, and it varies with raw materials of pigments. According to the colors of a different pigments, chemical compositions are as follows; for example, white pigments were used for a mixture of Pb(CO 3 ) 2 , PbSO 4 , PbO, Pb(OH) 2 , ZnO, ZnS, TiO 2 , BaSO 4 , CaCO 3 , Al 2 O 3 , As 2 S 3 , etc.; black pigments were series of carbon black, borne ash, MnO+Mn 2 O 3 , etc.; red pigments were Fe 2 O 3 , Pb 3 O 4 , HgS, PbMo 4 , CdS+CdSe, etc.; brown and yellow pigments were PbCrO 4 , ZnCrO 4 , CdS-ZnS, K 3 [Co(NO 2 ) 6 ], Pb(SbO 3 ) 2 , C 19 H 16 O 11 Mg, SrCrO 4 , etc.; green pigments were Cr 2 O 3 , Cr 2 O(OH) 4 , Cu(C 2 H 3 O 2 )-2Cu(OH) 2 ), Cr 2 O 3 -Al 2 O 3 -CoO, etc.; blue pigments were Fe 4 [Fe(CN) 6 ] 3 , CoO-Al 2 O 3 , Na 8 - 10 Al 6 Si 6 O 24 S 2-4 , etc. This first step is to obtain quantitative data on the concentrations of major, minor and trace elements in oil pigments and to explain pigment sources by statistical treatment as reported in many literatures. The determination of major, minor and micro elements in the subject materials are essential in many fields of basic science and technology as well as commercial and industrial fields. In particular, direct analysis of a sample offers a more effective investigation method in these fields. Instrumental neutron activation analysis (INAA) has an inherent advantage of being a non-destructive, simultaneously multi-elemental analysis with high accuracy and sensitivity. In order to characterize the elemental contents of art objects, the quantitative analysis of oil pigment series was

The Arabidopsis lyrata genome sequence and the basis of rapid genome size change

Energy Technology Data Exchange (ETDEWEB)

Hu, Tina T.; Pattyn, Pedro; Bakker, Erica G.; Cao, Jun; Cheng, Jan-Fang; Clark, Richard M.; Fahlgren, Noah; Fawcett, Jeffrey A.; Grimwood, Jane; Gundlach, Heidrun; Haberer, Georg; Hollister, Jesse D.; Ossowski, Stephan; Ottilar, Robert P.; Salamov, Asaf A.; Schneeberger, Korbinian; Spannagl, Manuel; Wang, Xi; Yang, Liang; Nasrallah, Mikhail E.; Bergelson, Joy; Carrington, James C.; Gaut, Brandon S.; Schmutz, Jeremy; Mayer, Klaus F. X.; Van de Peer, Yves; Grigoriev, Igor V.; Nordborg, Magnus; Weigel, Detlef; Guo, Ya-Long

2011-04-29

In our manuscript, we present a high-quality genome sequence of the Arabidopsis thaliana relative, Arabidopsis lyrata, produced by dideoxy sequencing. We have performed the usual types of genome analysis (gene annotation, dN/dS studies etc. etc.), but this is relegated to the Supporting Information. Instead, we focus on what was a major motivation for sequencing this genome, namely to understand how A. thaliana lost half its genome in a few million years and lived to tell the tale. The rather surprising conclusion is that there is not a single genomic feature that accounts for the reduced genome, but that every aspect centromeres, intergenic regions, transposable elements, gene family number is affected through hundreds of thousands of cuts. This strongly suggests that overall genome size in itself is what has been under selection, a suggestion that is strongly supported by our demonstration (using population genetics data from A. thaliana) that new deletions seem to be driven to fixation.

Characterization of pre-hispanic pigments by modern analytical techniques

International Nuclear Information System (INIS)

Ortega A, M.

2003-01-01

In this work, the study of mural painting pigments from two archaeological sites (The Great Temple in Mexico city and Cacaxtla) was performed to know their materials composition, identify their structural characteristics and properties by using modern analytical techniques. Blue, ochre, red and black pigments of Mexica culture (1325-1521 a.C. / late Post Classic period); blue, ochre, red, brown, pink, green and white of Olmeca- Xicalanca culture (700-900 a.C. / Epiclassic period) were studied. Data about materials used, technological evolution, mineralogical background, cultural interchange and origin was obtained. Environmental exposition of these paintings since their discovering has produced changes and damage on their materials. Therefore, stability of some pigments has been notorious, ''Maya Blue'' specially presents extraordinary resistance to diluted and concentrated acids and alkalis including boiling condition, acqua regia, solvents, oxidant and reducing agents, moderate heat and biocorrosi6n; for that reason its study was emphasized. ''Maya Blue'' pigment was synthesized in laboratory using the processes described by historic sources (with indigophera suffruticosa leaves and synthetic indigo) up to obtain a stable pigment including acqua regia action. Clay matrix sorbs nearly 0.4 weight percent of organic dye, which cover 79% of palygorskita surface area. (Author)

The importance of tattoo pigment in sentinel lymph nodes.

Science.gov (United States)

Soran, Atilla; Menekse, Ebru; Kanbour-Shakir, Amal; Tane, Kaori; Diego, Emilia; Bonaventura, Marguerite; Johnson, Ronald

2017-01-01

The presence of pigment in axillary lymph nodes (LN) secondary to migration of tattoo ink can imitate the appearance of a blue sentinel lymph node (SLN) on visual inspection, causing the operator to either miss the true SLN or excise more than is needed. We present patients with tattoos ipsilateral to an early stage breast cancer who underwent a SLN biopsy. Patients were retrospectively reviewed from medical records and clinicopathologic data was collected. A total of 52 LNs were retrieved from 15 patients for sentinel mapping and 29 of them had tattoo pigmentation on pathologic evaluation. Of those 29 SLNs, 2 of them (6.9%) were pigmented, but did not contain either blue dye or Tc-99m (pseudopigmented SLN). Two (3.8%) SLNs were positive for metastasis; both of these had either blue dye or Tc99m uptake, and 1 demonstrated tattoo pigment in the node. In this cohort of patients with ipsilateral tattoos, removed more LNs lead to unnecessary excision which may important for increasing the risk of arm morbidity from SLN biopsy. However, the presence of tattoo pigment did not interfere with understaging for axillary mapping and it did not effect of pathological identification of SLNs positivity.

40 CFR 415.340 - Applicability; description of the chrome pigments production subcategory.

Science.gov (United States)

2010-07-01

... chrome pigments production subcategory. 415.340 Section 415.340 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Chrome Pigments Production Subcategory § 415.340 Applicability; description of the chrome pigments production subcategory. This subpart applies to discharges to waters of the United States and...

The pigmentation of powder coatings with the use of block copolymer dispersants

NARCIS (Netherlands)

Duivenvoorde, F.L.; Nostrum, van C.F.; Linde, van der R.

1999-01-01

The dispersing of pigments in powder coatings is a difficult and complicated process. The incomplete dispersion under standard extrusion conditions can be attributed to a combination of poor pigment wetting and insufficient disruption of the pigment agglomerates, as a result of the rheological

Screening of Auricularia auricula strains for strong production ability of melanin pigments

OpenAIRE

ZOU, Yu; MA, Kun

2017-01-01

Abstract Melanin pigments have great application value and development potential in food industry to use as nature functional food colorants. In initial study, twenty-two Auricularia auricula strains were screened for stronger production ability of melanin pigments by solid culture. Three A. auricula strains (RF201, QD2 and QD6) with higher pigment production capacity were selected for further study through submerged culture supplementing 1 g/L l-tyrosine. The maximal pigment yields of A. aur...

75 FR 52930 - Carbazole Violet Pigment 23 From India: Preliminary Results of Antidumping Duty Changed...

Science.gov (United States)

2010-08-30

... of presscake and dry color. Pigment dispersions in any form (e.g., pigment dispersed in oleoresins... DEPARTMENT OF COMMERCE International Trade Administration [A-533-838] Carbazole Violet Pigment 23... order on carbazole violet pigment 23 from India to determine whether Meghmani Pigments (Meghmani) is the...

Pigments, parasites and personalitiy: towards a unifying role for steroid hormones?

Directory of Open Access Journals (Sweden)

Silje Kittilsen

Full Text Available A surging interest in the evolution of consistent trait correlations has inspired research on pigment patterns as a correlate of behavioural syndromes, or "animal personalities". Associations between pigmentation, physiology and health status are less investigated as potentially conserved trait clusters. In the current study, lice counts performed on farmed Atlantic salmon Salmo salar naturally infected with ectoparasitic sea lice Lepeophtheirus salmonis showed that individual fish with high incidence of black melanin-based skin spots harboured fewer female sea lice carrying egg sacs, compared to less pigmented fish. There was no significant association between pigmentation and lice at other developmental stages, suggesting that host factors associated with melanin-based pigmentation may modify ectoparasite development to a larger degree than settlement. In a subsequent laboratory experiment a strong negative correlation between skin spots and post-stress cortisol levels was revealed, with less pigmented individuals showing a more pronounced cortisol response to acute stress. The observation that lice prevalence was strongly increased on a fraction of sexually mature male salmon which occurred among the farmed fish further supports a role for steroid hormones as mediators of reduced parasite resistance. The data presented here propose steroid hormones as a proximate cause for the association between melanin-based pigmentation and parasites. Possible fundamental and applied implications are discussed.

Refractory Pigmentation Associated with Laugier-Hunziker Syndrome following Er:YAG Laser Treatment.

Science.gov (United States)

Ergun, Sertan; Saruhanoğlu, Alp; Migliari, Dante-Antonio; Maden, Ilay; Tanyeri, Hakkı

2013-01-01

The present report describes a case of Laugier-Hunziker syndrome (LHS), a rare benign condition. A patient with LHS develops acquired melanotic pigmentation of the lips and buccal mucosa, often with pigmentation of the nails occurring. No systemic symptoms are associated with this syndrome. Normally, no treatment is required for this condition, unless for aesthetic reason, mainly due to pigmentation on the lip mucosa. We present a case of LHS, 37-year-old female, whose pigmentations on her lip and in the oral cavity were treated with an Er:YAG laser. At the postoperative 12th month followup, the lesions recurred. The effects of any surgical attempt to treat pigmentations associated with LHS were discussed.

Synthesis and characterization of black, red and yellow nanoparticles pigments from the iron sand

International Nuclear Information System (INIS)

Mufti, Nandang; Atma, T.; Fuad, A.; Sutadji, E.

2014-01-01

The aim of this research is to synthesize nanoparticles of black pigment of Magnetite (Fe 3 O 4 ), red pigment of hematite (α-Fe 2 O 3 ), and yellow pigment of ghoetite (α-FeOOH) from the iron sand. The black pigment of Fe 3 O 4 and the yellow pigment α-FeOOH nanoparticles were synthesized by coprecipitation method with variation of pH. Whereas, the red pigment Fe 2 O 3 was synthesized by sintering Fe 3 O 4 nanoparticles at temperature between 400 °C and 700 7°C for 1 hour. All the pigments has been characterized using X-ray diffraction and SEM. The XRD results shown that the particle size of the black pigmen Fe 3 O 4 , red pigment Fe 3 O 4 and yellow pigment α-FeOOH are around 12, 32, and 30 nm respectively. The particle size of Fe 2 O 3 nanoparticles increase by increasing sintering temperature from 32 nm at 400 °C to 39 nm at 700 °C. For yellow pigment of α-FeOOH, the particle size increase by increasing pH from 30,54 nm at pH 4 to 48,60 nm at pH 7. The SEM results shown that the morphologies of black, yellow and red pigments are aglomarated

A microarray analysis of the rice transcriptome and its comparison to Arabidopsis

DEFF Research Database (Denmark)

Ma, Ligeng; Chen, Chen; Liu, Xigang

2005-01-01

Arabidopsis and rice are the only two model plants whose finished phase genome sequence has been completed. Here we report the construction of an oligomer microarray based on the presently known and predicted gene models in the rice genome. This microarray was used to analyze the transcriptional...... with similar genome-wide surveys of the Arabidopsis transcriptome, our results indicate that similar proportions of the two genomes are expressed in their corresponding organ types. A large percentage of the rice gene models that lack significant Arabidopsis homologs are expressed. Furthermore, the expression...... patterns of rice and Arabidopsis best-matched homologous genes in distinct functional groups indicate dramatic differences in their degree of conservation between the two species. Thus, this initial comparative analysis reveals some basic similarities and differences between the Arabidopsis and rice...

Clonal origins of cells in the pigmented retina of the zebrafish eye

International Nuclear Information System (INIS)

Streisinger, G.; Coale, F.; Taggart, C.; Walker, C.; Grunwald, D.J.

1989-01-01

Mosaic analysis has been used to study the clonal basis of the development of the pigmented retina of the zebrafish, Brachydanio rerio. Zebrafish embryos heterozygous for a recessive mutation at the gol-1 locus were exposed to gamma-irradiation at various developmental stages to create mosaic individuals consisting of wild-type pigmented cells and a clone of pigmentless (golden) cells in the eye. The contribution of individual embryonic cells to the pigmented retina was measured and the total number of cells in the embryo that contributed descendants to this tissue was determined. Until the 32-cell stage, almost every blastomere has some descendants that participate in the formation of the pigmented retina of the zebrafish. During subsequent cell divisions, up to the several thousand-cell stage, the number of ancestral cells is constant: approximately 40 cells are present that will give rise to progeny in the pigmented retina. Analysis of the size of clones in the pigmented retina indicates that the cells of this tissue do not arise through a rigid series of cell divisions originating in the early embryo. The findings that each cleavage stage cell contributes to the pigmented retina and yet the contribution of such cells is highly variable are consistent with the interpretation that clonal descendants of different blastomeres normally intermix extensively prior to formation of the pigmented retina

Suppression of PCD-related genes affects salt tolerance in Arabidopsis.

Science.gov (United States)

Bahieldin, Ahmed; Alqarni, Dhafer A M; Atef, Ahmed; Gadalla, Nour O; Al-matary, Mohammed; Edris, Sherif; Al-Kordy, Magdy A; Makki, Rania M; Al-Doss, Abdullah A; Sabir, Jamal S M; Mutwakil, Mohammed H Z; El-Domyati, Fotouh M

2016-01-01

This work aims at examining a natural exciting phenomenon suggesting that suppression of genes inducing programmed cell death (PCD) might confer tolerance against abiotic stresses in plants. PCD-related genes were induced in tobacco under oxalic acid (OA) treatment (20 mM), and plant cells were characterized to confirm the incidence of PCD. The results indicated that PCD was triggered 24 h after the exposure to OA. Then, RNAs were extracted from tobacco cells 0, 2, 6, 12 and 24 h after treatment for deep sequencing. RNA-Seq analyses were done with a special emphasis to clusters whose PCD-related genes were upregulated after 2 h of OA exposure. Accordingly, 23 tobacco PCD-related genes were knocked down via virus-induced gene silencing (VIGS), whereas our results indicated the influence of five of them on inducing or suppressing PCD. Knockout T-DNA insertion mutants of these five genes in Arabidopsis were tested under salt stress (0, 100, 150, and 200 mM NaCl), and the results indicated that a mutant of an antiapoptotic gene, namely Bax Inhibitor-1 (BI-1), whose VIGS induced PCD in tobacco, was salt sensitive, while a mutant of an apoptotic gene, namely mildew resistance locus O (Mlo), whose VIGS suppressed PCD, was salt tolerant as compared to the WT (Col) control. These data support our hypothesis that retarding PCD-inducing genes can result in higher levels of salt tolerance, while retarding PCD-suppressing genes can result in lower levels of salt tolerance in plants. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Cone visual pigments are present in gecko rod cells.

Science.gov (United States)

Kojima, D; Okano, T; Fukada, Y; Shichida, Y; Yoshizawa, T; Ebrey, T G

1992-08-01

The Tokay gecko (Gekko gekko), a nocturnal lizard, has two kinds of visual pigments, P467 and P521. In spite of the pure-rod morphology of the photoreceptor cells, the biochemical properties of P521 and P467 resemble those of iodopsin (the chicken red-sensitive cone visual pigment) and rhodopsin, respectively. We have found that the amino acid sequence of P521 deduced from the cDNA was very similar to that of iodopsin. In addition, P467 has the highest homology with the chicken green-sensitive cone visual pigment, although it also has a relatively high homology with rhodopsins. These results give additional strength to the transmutation theory of Walls [Walls, G. L. (1934) Am. J. Ophthalmol. 17, 892-915], who proposed that the rod-shaped photoreceptor cells of lizards have been derived from ancestral cone-like photoreceptors. Apparently amino acid sequences of visual pigments are less changeable than the morphology of the photoreceptor cells in the course of evolution.

Radiation degradation of molasses pigment. 2. Molecular weight fraction

International Nuclear Information System (INIS)

Sawai, Teruko; Sekiguchi, Masayuki; Tanabe, Hiroko

1996-01-01

Water demand in Tokyo has increased rapidly. Because of the scarcity of water sources within the city, Tokyo is dependent on water from other prefectures. Recycling of municipal effluent is an effective means of coping with water shortage in Tokyo. We have studied the radiation treatment of waste water for recycling. The degradation of molasses pigments in waste water from yeast factory by radiation was investigated. The dialyzed molasses pigments and non-dialyzed samples in waste waters were compared in chromaticity, UV absorption, color different and COD. The dialysis and fractionation by permeable membrane were carried out with Seamless Cellulose tubing (Union Carbide Corporation) and spectra/Por membrane (Spectrum Medical Industries INC.) The TOC values decreased and the dark brown color faded with increasing dose. The high molecular weight components of molasses pigment were degraded to lower molecular weight substances and decomposed to carbon dioxide. The relationships between the value of chromaticity/TOC and molecular weight of molasses pigments were obtained by radiation. (author)

New insights into melanosome transport in vertebrate pigment cells.

Science.gov (United States)

Aspengren, Sara; Hedberg, Daniel; Sköld, Helen Nilsson; Wallin, Margareta

2009-01-01

Pigment cells of lower vertebrates provide an excellent model to study organelle transport as they specialize in the translocation of pigment granules in response to defined chemical cues. This review will focus on the well-studied melanophore/melanocyte systems in fish, amphibians, and mammals. We will describe the roles of melanin, melanophores, and melanocytes in animals, current views on how the three motor proteins dynein, kinesin, and myosin-V are involved in melanosome transport along microtubules and actin filaments, and how signal transduction pathways regulate the activities of the motors to achieve aggregation and dispersion of melanosomes. We will also describe how melanosomes are transferred to surrounding skin cells in amphibians and mammals. Comparative studies have revealed that the ability of physiological color change is lost during evolution while the importance of morphological color change, mainly via transfer of pigment to surrounding skin cells, increases. In humans, pigment mainly has a role in protection against ultraviolet radiation, but also perhaps in the immune system.

[Synthesis and characterization of chromium doped Y3Al5O12 compound pigment].

Science.gov (United States)

Yue, Shi-Juan; Su, Xiao; Jiang, Han-Jie; Liu, Shao-Xuan; Hong, You-Li; Zhang, Kai; Huang, Wan-Xias; Xiong, Zu-Jiang; Zhao, Ying; Liu, Cui-Ge; Wei, Yong-Ju; Meng, Tao; Xu, Yi-Zhuang; Wu, Jin-Guang

2012-09-01

The authors synthesized a new kind of green pigment via co-precipitation method by doping Y3Al5O12 with Cr+. The size of the pigment particles is around 200 nm as observed under scanning electron microscope. XRD results demonstrate that the pigment crystalline form of the pigment is yttrium alluminium garnet. UV-Vis spectra were used to investigate the coordination states and transition behavior of the doping ions. In addition, the colour feature was measured by CIE L* a* b* chroma value. The pigment was blended with polypropylene and then polypropylene fiber was produced using the polypropelene-pigment composite via molten spinning process. The distribution of the pigment particles in the polypropylene fibers was characterized by Xray computed tomography (CT) technique on the Beijing synchrotron radiation facility. The result states that the composite oxide pigment particles are homogeneously dispersed in the polypropylene fibers. The pigments are stable, non-toxic to the environment, and may be applied in non-aqueous dyeing to reduce waste water emitted by textile dyeing and printing industry.

Direct transcriptional activation of BT genes by NLP transcription factors is a key component of the nitrate response in Arabidopsis.

Science.gov (United States)

Sato, Takeo; Maekawa, Shugo; Konishi, Mineko; Yoshioka, Nozomi; Sasaki, Yuki; Maeda, Haruna; Ishida, Tetsuya; Kato, Yuki; Yamaguchi, Junji; Yanagisawa, Shuichi

2017-01-29

Nitrate modulates growth and development, functioning as a nutrient signal in plants. Although many changes in physiological processes in response to nitrate have been well characterized as nitrate responses, the molecular mechanisms underlying the nitrate response are not yet fully understood. Here, we show that NLP transcription factors, which are key regulators of the nitrate response, directly activate the nitrate-inducible expression of BT1 and BT2 encoding putative scaffold proteins with a plant-specific domain structure in Arabidopsis. Interestingly, the 35S promoter-driven expression of BT2 partially rescued growth inhibition caused by reductions in NLP activity in Arabidopsis. Furthermore, simultaneous disruption of BT1 and BT2 affected nitrate-dependent lateral root development. These results suggest that direct activation of BT1 and BT2 by NLP transcriptional activators is a key component of the molecular mechanism underlying the nitrate response in Arabidopsis. Copyright © 2016 Elsevier Inc. All rights reserved.

The power of pigments, calibrating chemoclines with chlorophylls and carotenoids.

Science.gov (United States)

Junium, C. K.; Uveges, B. T.

2017-12-01

Phototrophic organisms produce a diversity of pigments that serve a broad range of specific biochemical functions. Pigments are either directly associated with the photosynthetic apparatus, the most notable being chlorophyll a, or are accessory pigments such as the carotenoid lutein. Their functions can also be categorized into roles that are related to light harvesting (e.g. fucoxanthin) or for photoprotection (e.g. scytonemin). The abundances of these two classes of pigments from environmental samples can provide specific information about photointensity and how it relates to environmental changes. For example, a deepening of the chemo/nutricline can result in the increased production of light gathering relative to photoprotective pigments. Here we apply a relatively simple approach that utilizes the abundance of photosynthetic relative to photoprotective pigments to help constrain changes in the water column position of the chemocline. To test the efficacy of this approach we have utilized the sedimentary record of the anoxic Lake Kivu in the East African Rift. Recent Lake Kivu sediments are punctuated by a series of sapropels that may be associated with overturn of the lake, and release of carbon dioxide and sulfide during potential limnic eruptions. Carbon and nitrogen isotopes decrease significantly at the onset of sapropel deposition and suggest that 13C-depleted dissolved inorganic carbon was upwelled into surface waters and was accompanied by high concentrations of ammonium, that allowed for 15N-depletion during incomplete nitrogen utilization. The pigment record, specifically the ratio of the photoprotective carotenoids lutein and zeaxanthin to chlorophyll a increases significantly at the onset of sapropel deposition. This suggests that the chemocline shallowed, displacing phototrophic communities toward the surface of the lake where light intensities required production of photoprotective pigments. This approach can easily be applied to a wide variety of

Ocular distribution of topically applied adrenaline in albino and pigmented rabbits

International Nuclear Information System (INIS)

Urtti, A.; Periviita, L.; Salminen, L.

1984-01-01

Systemic absorption, ocular distribution and ocular metabolism in albino and pigmented rabbit of topically applied 1% [ 3 H]1-adrenaline eye drops was studied by liquid scintillation counting and thin layer chromatography. The effect of adrenaline on the pupillary diameter was also registered. The peak plasma level of adrenaline was reached at 150 min. The corneal adrenaline metabolism was substantial, but did not vary with the rabbit strain. At 30 min after instillation, the total adrenaline concentration of pigmented iris and ciliary body exceeded that of corresponding albino tissues. At 180 min the drug concentration of the iris and ciliary body did not differ between the rabbit strains. Th time course of adrenaline induced mydriasis was equal in both rabbit strains. Since neither total adrenaline concentration at 180 min nor the time course of adrenaline induced mydriasis differed between the rabbit strains, the higher initial adrenaline uptake by pigmented tissues is not explained by pigment binding. It is proposed that the increased initial binding of adrenaline by pigmented tissues is caused by a difference between pigmented and albino tissues in the number of adrenergic neurones; this is also supported by the literature. (author)

Structures and colour properties of new red wine pigments

DEFF Research Database (Denmark)

Håkansson, Anders Eckart; Pardon, K.; Hayasaka, Y.

2003-01-01

the colour properties of the pigments were characterized; it could be demonstrated that the pyranoanthocyanins retained their red colour at pH 3.6 in model wine and were resistant to bisulfite-mediated bleaching. Finally, HPLC-MS analysis confirmed the presence of both anthocyanin-derived pigments in red...... wine....

Optimal methodologies for terahertz time-domain spectroscopic analysis of traditional pigments in powder form

Science.gov (United States)

Ha, Taewoo; Lee, Howon; Sim, Kyung Ik; Kim, Jonghyeon; Jo, Young Chan; Kim, Jae Hoon; Baek, Na Yeon; Kang, Dai-ill; Lee, Han Hyoung

2017-05-01

We have established optimal methods for terahertz time-domain spectroscopic analysis of highly absorbing pigments in powder form based on our investigation of representative traditional Chinese pigments, such as azurite [blue-based color pigment], Chinese vermilion [red-based color pigment], and arsenic yellow [yellow-based color pigment]. To accurately extract the optical constants in the terahertz region of 0.1 - 3 THz, we carried out transmission measurements in such a way that intense absorption peaks did not completely suppress the transmission level. This required preparation of pellet samples with optimized thicknesses and material densities. In some cases, mixing the pigments with polyethylene powder was required to minimize absorption due to certain peak features. The resulting distortion-free terahertz spectra of the investigated set of pigment species exhibited well-defined unique spectral fingerprints. Our study will be useful to future efforts to establish non-destructive analysis methods of traditional pigments, to construct their spectral databases, and to apply these tools to restoration of cultural heritage materials.

Overexpression of an Arabidopsis heterogeneous nuclear ribonucleoprotein gene, AtRNP1, affects plant growth and reduces plant tolerance to drought and salt stresses

International Nuclear Information System (INIS)

Wang, Zhenyu; Zhao, Xiuyang; Wang, Bing; Liu, Erlong; Chen, Ni; Zhang, Wei; Liu, Heng

2016-01-01

Heterogeneous nuclear ribonucleoproteins (hnRNPs) participate in diverse regulations of plant growth and environmental stress responses. In this work, an Arabidopsis hnRNP of unknown function, AtRNP1, was investigated. We found that AtRNP1 gene is highly expressed in rosette and cauline leaves, and slightly induced under drought, salt, osmotic and ABA stresses. AtRNP1 protein is localized to both the nucleus and cytoplasm. We performed homologous overexpression of AtRNP1 and found that the transgenic plants showed shortened root length and plant height, and accelerated flowering. In addition, the transgenic plants also showed reduced tolerance to drought, salt, osmotic and ABA stresses. Further studies revealed that under both normal and stress conditions, the proline contents in the transgenic plants are markedly decreased, associated with reduced expression levels of a proline synthase gene and several stress-responsive genes. These results suggested that the overexpression of AtRNP1 negatively affects plant growth and abiotic stress tolerance. - Highlights: • AtRNP1 is a widely expressed gene and its expression is slightly induced under abiotic stresses. • AtRNP1 protein is localized to both the nucleus and cytoplasm. • Overexpression of AtRNP1 affects plant growth. • Overexpression of AtRNP1 reduces plant tolerance to drought and salt stresses. • AtRNP1 overexpression plants show decreased proline accumulation and stress-responsive gene expressions.

Overexpression of an Arabidopsis heterogeneous nuclear ribonucleoprotein gene, AtRNP1, affects plant growth and reduces plant tolerance to drought and salt stresses

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhenyu, E-mail: wzy72609@163.com [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China); Zhao, Xiuyang, E-mail: xiuzh@psb.vib-ugent.be [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China); Wang, Bing, E-mail: wangbing@ibcas.ac.cn [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China); Liu, Erlong, E-mail: liuel14@lzu.edu.cn [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China); Chen, Ni, E-mail: 63710156@qq.com [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China); Zhang, Wei, E-mail: wzhang1216@yahoo.com [Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444 (China); Liu, Heng, E-mail: hengliu@lzu.edu.cn [Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730030 (China)

2016-04-01

Heterogeneous nuclear ribonucleoproteins (hnRNPs) participate in diverse regulations of plant growth and environmental stress responses. In this work, an Arabidopsis hnRNP of unknown function, AtRNP1, was investigated. We found that AtRNP1 gene is highly expressed in rosette and cauline leaves, and slightly induced under drought, salt, osmotic and ABA stresses. AtRNP1 protein is localized to both the nucleus and cytoplasm. We performed homologous overexpression of AtRNP1 and found that the transgenic plants showed shortened root length and plant height, and accelerated flowering. In addition, the transgenic plants also showed reduced tolerance to drought, salt, osmotic and ABA stresses. Further studies revealed that under both normal and stress conditions, the proline contents in the transgenic plants are markedly decreased, associated with reduced expression levels of a proline synthase gene and several stress-responsive genes. These results suggested that the overexpression of AtRNP1 negatively affects plant growth and abiotic stress tolerance. - Highlights: • AtRNP1 is a widely expressed gene and its expression is slightly induced under abiotic stresses. • AtRNP1 protein is localized to both the nucleus and cytoplasm. • Overexpression of AtRNP1 affects plant growth. • Overexpression of AtRNP1 reduces plant tolerance to drought and salt stresses. • AtRNP1 overexpression plants show decreased proline accumulation and stress-responsive gene expressions.

The relationship between the violet pigment PP-V production and intracellular ammonium level in Penicillium purpurogenum

OpenAIRE

Kojima, Ryo; Arai, Teppei; Matsufuji, Hiroshi; Kasumi, Takafumi; Watanabe, Taisuke; Ogihara, Jun

2016-01-01

Penicillium purpurogenum is the fungus that produces an azaphilone pigment. However, details about the pigment biosynthesis pathway are unknown. The violet pigment PP-V is the one of the main pigments biosynthesized by this fungus. This pigment contains an amino group in a pyran ring as its core structure. We focused on this pigment and examined the relationship between intracellular ammonium concentration and pigment production using glutamine as a nitrogen source. The intracellular ammonium...

An investigation of multispectral imaging for the mapping of pigments in paintings

Science.gov (United States)

Zhao, Yonghui; Berns, Roy S.; Taplin, Lawrence A.; Coddington, James

2008-02-01

Compared with colorimetric imaging, multispectral imaging has the advantage of retrieving spectral reflectance factor of each pixel of a painting. Using this spectral information, pigment mapping is concerned with decomposing the spectrum into its constituent pigments and their relative contributions. The output of pigment mapping is a series of spatial concentration maps of the pigments comprising the painting. This approach was used to study Vincent van Gogh's The Starry Night. The artist's palette was approximated using ten oil pigments, selected from a large database of pigments used in oil paintings and a priori analytical research on one of his self portraits, executed during the same time period. The pigment mapping was based on single-constant Kubelka-Munk theory. It was found that the region of blue sky where the stars were located contained, predominantly, ultramarine blue while the swirling sky and region surrounding the moon contained, predominantly, cobalt blue. Emerald green, used in light bluish-green brushstrokes surrounding the moon, was not used to create the dark green in the cypresses. A measurement of lead white from Georges Seurat's La Grande Jatte was used as the white when mapping The Starry Night. The absorption and scattering properties of this white were replaced with a modern dispersion of lead white in linseed oil and used to simulate the painting's appearance before the natural darkening and yellowing of lead white oil paint. Pigment mapping based on spectral imaging was found to be a viable and practical approach for analyzing pigment composition, providing new insight into an artist's working method, the possibility for aiding in restorative inpainting, and lighting design.

Melanocortin systems on pigment dispersion in fish chromatophores.

Science.gov (United States)

Kobayashi, Yuki; Mizusawa, Kanta; Saito, Yumiko; Takahashi, Akiyoshi

2012-01-01

α-Melanocyte-stimulating hormone (α-MSH) is responsible for pigment dispersion in the chromatophores of fish and other tetrapods such as amphibians and reptiles. Recently, we discovered that α-MSH did not always stimulate pigment dispersion because this hormonal peptide exerted no effects on the melanophores of flounders. We assumed that the reduction of α-MSH activity was related to the co-expression of different α-MSH receptor subtypes - termed melanocortin receptors (MCR) - a member of G-protein-coupled receptors (GPCR) - based on several reports demonstrating that GPCR forms heterodimers with various properties that are distinct from those of the corresponding monomers. In this review, we summarize the relationships between the pigment-dispersing activity of α-MSH-related peptides, molecular forms of α-MSH-related peptides, and mcr subtypes expressed in fish chromatophores.

Primary description of surface water phytoplankton pigment patterns in the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Naik, R.K.; Anil, A; Narale, D.D.; Chitari, R.R.; Kulkarni, V.V.

. Comparison of pigment data with microscopic cell counts indicated a significant relationship between the diatom pigment index (Diat sub (DP)) and diatom abundance. However, the relationship between the dinoflagellate pigment index (Dino sub (DP...

Evolutionary origins of Brassicaceae specific genes in Arabidopsis thaliana

Science.gov (United States)

2011-01-01

Background All sequenced genomes contain a proportion of lineage-specific genes, which exhibit no sequence similarity to any genes outside the lineage. Despite their prevalence, the origins and functions of most lineage-specific genes remain largely unknown. As more genomes are sequenced opportunities for understanding evolutionary origins and functions of lineage-specific genes are increasing. Results This study provides a comprehensive analysis of the origins of lineage-specific genes (LSGs) in Arabidopsis thaliana that are restricted to the Brassicaceae family. In this study, lineage-specific genes within the nuclear (1761 genes) and mitochondrial (28 genes) genomes are identified. The evolutionary origins of two thirds of the lineage-specific genes within the Arabidopsis thaliana genome are also identified. Almost a quarter of lineage-specific genes originate from non-lineage-specific paralogs, while the origins of ~10% of lineage-specific genes are partly derived from DNA exapted from transposable elements (twice the proportion observed for non-lineage-specific genes). Lineage-specific genes are also enriched in genes that have overlapping CDS, which is consistent with such novel genes arising from overprinting. Over half of the subset of the 958 lineage-specific genes found only in Arabidopsis thaliana have alignments to intergenic regions in Arabidopsis lyrata, consistent with either de novo origination or differential gene loss and retention, with both evolutionary scenarios explaining the lineage-specific status of these genes. A smaller number of lineage-specific genes with an incomplete open reading frame across different Arabidopsis thaliana accessions are further identified as accession-specific genes, most likely of recent origin in Arabidopsis thaliana. Putative de novo origination for two of the Arabidopsis thaliana-only genes is identified via additional sequencing across accessions of Arabidopsis thaliana and closely related sister species

Characteristic Elemental Composition of Oil Pigments using Instrumental Neutron Activation Analysis

Energy Technology Data Exchange (ETDEWEB)

Chung, Yong Sam; Kim, Sun Ha; Sun, Gwang Min; Lim, Jong Myung; Moon, Jong Hwa; Kim, Young Jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lim, Sung Jin; Song, Yu Na; Kim, Ken [National Museum of Contemporary Art, Gwacheon (Korea, Republic of)

2009-10-15

The principal aim of this study is to identify the applicability of instrumental neutron activation analysis as a non-destructive examination tool for the quantitative composition analysis associated with authentication, restoration, and conservation of art objects in the field of cultural heritage. Generally, the chemical composition of pigments are associated with the colors such as white, yellow, orange, red, green, blue and black, and it varies with raw materials of pigments. According to the colors of a different pigments, chemical compositions are as follows; for example, white pigments were used for a mixture of Pb(CO{sub 3}){sub 2}, PbSO{sub 4}, PbO, Pb(OH){sub 2}, ZnO, ZnS, TiO{sub 2}, BaSO{sub 4}, CaCO{sub 3}, Al{sub 2}O{sub 3}, As{sub 2}S{sub 3}, etc.; black pigments were series of carbon black, borne ash, MnO+Mn{sub 2}O{sub 3}, etc.; red pigments were Fe{sub 2}O{sub 3}, Pb{sub 3}O{sub 4}, HgS, PbMo{sub 4}, CdS+CdSe, etc.; brown and yellow pigments were PbCrO{sub 4}, ZnCrO{sub 4}, CdS-ZnS, K{sub 3}[Co(NO{sub 2}){sub 6}], Pb(SbO{sub 3}){sub 2}, C{sub 19}H{sub 16}O{sub 11}Mg, SrCrO{sub 4}, etc.; green pigments were Cr{sub 2}O{sub 3}, Cr{sub 2}O(OH){sub 4}, Cu(C{sub 2}H{sub 3}O{sub 2})-2Cu(OH){sub 2}), Cr{sub 2}O{sub 3}-Al{sub 2}O{sub 3}-CoO, etc.; blue pigments were Fe{sub 4}[Fe(CN){sub 6}]{sub 3}, CoO-Al{sub 2}O{sub 3}, Na{sub 8}-{sub 10}Al{sub 6}Si{sub 6}O{sub 24}S{sub 2-4}, etc. This first step is to obtain quantitative data on the concentrations of major, minor and trace elements in oil pigments and to explain pigment sources by statistical treatment as reported in many literatures. The determination of major, minor and micro elements in the subject materials are essential in many fields of basic science and technology as well as commercial and industrial fields. In particular, direct analysis of a sample offers a more effective investigation method in these fields. Instrumental neutron activation analysis (INAA) has an inherent advantage of being a

Natural genetic variation in Arabidopsis thaliana defense metabolism genes modulates field fitness

Science.gov (United States)

Kerwin, Rachel; Feusier, Julie; Corwin, Jason; Rubin, Matthew; Lin, Catherine; Muok, Alise; Larson, Brandon; Li, Baohua; Joseph, Bindu; Francisco, Marta; Copeland, Daniel; Weinig, Cynthia; Kliebenstein, Daniel J

2015-01-01

Natural populations persist in complex environments, where biotic stressors, such as pathogen and insect communities, fluctuate temporally and spatially. These shifting biotic pressures generate heterogeneous selective forces that can maintain standing natural variation within a species. To directly test if genes containing causal variation for the Arabidopsis thaliana defensive compounds, glucosinolates (GSL) control field fitness and are therefore subject to natural selection, we conducted a multi-year field trial using lines that vary in only specific causal genes. Interestingly, we found that variation in these naturally polymorphic GSL genes affected fitness in each of our environments but the pattern fluctuated such that highly fit genotypes in one trial displayed lower fitness in another and that no GSL genotype or genotypes consistently out-performed the others. This was true both across locations and within the same location across years. These results indicate that environmental heterogeneity may contribute to the maintenance of GSL variation observed within Arabidopsis thaliana. DOI: http://dx.doi.org/10.7554/eLife.05604.001 PMID:25867014

Simulated microgravity, Mars gravity, and 2g hypergravity affect cell cycle regulation, ribosome biogenesis, and epigenetics in Arabidopsis cell cultures.

Science.gov (United States)

Kamal, Khaled Y; Herranz, Raúl; van Loon, Jack J W A; Medina, F Javier

2018-04-23

Gravity is the only component of Earth environment that remained constant throughout the entire process of biological evolution. However, it is still unclear how gravity affects plant growth and development. In this study, an in vitro cell culture of Arabidopsis thaliana was exposed to different altered gravity conditions, namely simulated reduced gravity (simulated microgravity, simulated Mars gravity) and hypergravity (2g), to study changes in cell proliferation, cell growth, and epigenetics. The effects after 3, 14, and 24-hours of exposure were evaluated. The most relevant alterations were found in the 24-hour treatment, being more significant for simulated reduced gravity than hypergravity. Cell proliferation and growth were uncoupled under simulated reduced gravity, similarly, as found in meristematic cells from seedlings grown in real or simulated microgravity. The distribution of cell cycle phases was changed, as well as the levels and gene transcription of the tested cell cycle regulators. Ribosome biogenesis was decreased, according to levels and gene transcription of nucleolar proteins and the number of inactive nucleoli. Furthermore, we found alterations in the epigenetic modifications of chromatin. These results show that altered gravity effects include a serious disturbance of cell proliferation and growth, which are cellular functions essential for normal plant development.

75 FR 29719 - Carbazole Violet Pigment 23 From India: Continuation of Countervailing Duty Order

Science.gov (United States)

2010-05-27

..., paste, wet cake) and finished pigment in the form of presscake and dry color. Pigment dispersions in any... DEPARTMENT OF COMMERCE International Trade Administration [C-533-839] Carbazole Violet Pigment 23... Pigment 23 From India, 69 FR 77995 (December 29, 2004). On November 2, 2009, the Department initiated and...

Soil mixture composition alters Arabidopsis susceptibility to Pseudomonas syringae infection

Science.gov (United States)

Pseudomonas syringae is a Gram-negative bacterial pathogen that causes disease on more than 100 different plant species, including the model plant Arabidopsis thaliana. Dissection of the Arabidopsis thaliana-Pseudomonas syringae pathosystem has identified many factors that contribute to successful ...

The effect of pigment matrix, temperature and amount of carrier on the yield and final color properties of spray dried purple corn (Zea mays L.) cob anthocyanin powders.

Science.gov (United States)

Lao, Fei; Giusti, M Monica

2017-07-15

Spray drying is an economic technique to produce anthocyanin-based colorants. High pigments yields with minimum color degradation are desirable to maximize quality and profits. This study evaluated the impacts of purple corncob (PCC) anthocyanin extraction matrices (hot water, 40% ethanol, C18 purified), drying inlet temperature (130, 150, 170°C) and amount of carrier (2%, 5%, 10% maltodextrin) on the yields and quality of PCC anthocyanin powders. Monomeric and polymeric anthocyanins, color properties (CIELch, haze), and pigments composition before and after spray drying were determined. The yield and final color quality of spray dried PCC anthocyanins were affected (p<0.05) by all parameters evaluated. The pigment matrix, inlet temperature, and carrier amount had biggest impacts on product water solubility, pigments degradation and yield, respectively. The optimal combination of hot water extracts spray dried with 5% maltodextrin at 150°C gave the highest pigment yield (∼90%) with good solubility with the least color loss. Copyright © 2017 Elsevier Ltd. All rights reserved.

Production of water-soluble yellow pigments via high glucose stress fermentation of Monascus ruber CGMCC 10910.

Science.gov (United States)

Wang, Meihua; Huang, Tao; Chen, Gong; Wu, Zhenqiang

2017-04-01

Monascus pigments are secondary metabolites of Monascus species and are mainly composed of yellow pigments, orange pigments and red pigments. In this study, a larger proportion of Monascus yellow pigments could be obtained through the selection of the carbon source. Hydrophilic yellow pigments can be largely produced extracellularly by Monascus ruber CGMCC 10910 under conditions of high glucose fermentation with low oxidoreduction potential (ORP). However, keeping high glucose levels later in the culture causes translation or a reduction of yellow pigment. We presume that the mechanism behind this phenomenon may be attributed to the redox level of the culture broth and the high glucose stress reaction of M. ruber CGMCC 10910 during high glucose fermentation. These yellow pigments were produced via high glucose bio-fermentation without citrinin. Therefore, these pigments can act as natural pigments for applications as food additives.

The DnaJ-like zinc finger domain protein PSA2 affects light acclimation and chloroplast development in Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Yan-Wen eWang

2016-03-01

Full Text Available The biosynthesis of chlorophylls and carotenoids and the assembly of thylakoid membranes are critical for the photoautotrophic growth of plants. Different factors are involved in these two processes. In recent years, members of the DnaJ-like zinc finger domain proteins have been found to take part in the biogenesis and/or the maintenance of plastids. One member of this family of proteins, PSA2, was recently found to localize to the thylakoid lumen and regulate the accumulation of photosystem I. In this study, we report that the silencing of PSA2 in Arabidopsis thaliana resulted in variegated leaves and retarded growth. Although both chlorophylls and total carotenoids decreased in the psa2 mutant, violaxanthin and zeaxanthin accumulated in the mutant seedlings grown under growth condition. Lower levels of non-photochemical quenching and electron transport rate were also found in the psa2 mutant seedlings under growth condition compared with those of the wild-type plants, indicating an impaired capability to acclimate to normal light irradiance when PSA2 was silenced. Moreover, we also observed an abnormal assembly of grana thylakoids and poorly developed stroma thylakoids in psa2 chloroplasts. Taken together, our results demonstrate that PSA2 is a member of the DnaJ-like zinc finger domain protein family that affects light acclimation and chloroplast development.

A comprehensive study of eco-friendly natural pigment and its applications

OpenAIRE

Parmar, Ramendra Singh; Singh, Charu

2017-01-01

Actinomycetes, a large group of filamentous bacteria account for 70–80% of secondary metabolites available commercially. The present investigation was undertaken with an aim to identify and characterize pigment from actinomycetes. Actinomycetes were isolated from rhizosphere soil samples collected from different regions of Madhya Pradesh state. Out of 85 actinomycetes, only 5 actinomycetes showed pigment production and based on diffusible pigment production ability one actinomycete ARITM02 wa...

Controlling composition and color characteristics of Monascus pigments by pH and nitrogen sources in submerged fermentation.

Science.gov (United States)

Shi, Kan; Song, Da; Chen, Gong; Pistolozzi, Marco; Wu, Zhenqiang; Quan, Lei

2015-08-01

Submerged fermentations of Monascus anka were performed with different nitrogen sources at different pH in 3 L bioreactors. The results revealed that the Monascus pigments dominated by different color components (yellow pigments, orange pigments or red pigments) could be selectively produced through pH control and nitrogen source selection. A large amount of intracellular pigments dominated by orange pigments and a small amount of water-soluble extracellular yellow pigments were produced at low pH (pH 2.5 and 4.0), independently of the nitrogen source employed. At higher pH (pH 6.5), the role of the nitrogen source became more significant. In particular, when ammonium sulfate was used as nitrogen source, the intracellular pigments were dominated by red pigments with a small amount of yellow pigments. Conversely, when peptone was used, intracellular pigments were dominated by yellow pigments with a few red pigments derivatives. Neither the presence of peptone nor ammonium sulfate promoted the production of intracellular orange pigments while extracellular pigments with an orangish red color were observed in both cases, with a higher yield when peptone was used. Two-stage pH control fermentation was then performed to improve desirable pigments yield and further investigate the effect of pH and nitrogen sources on pigments composition. These results provide a useful strategy to produce Monascus pigments with different composition and different color characteristics. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Adsorption and inhibition of CuO nanoparticles on Arabidopsis thaliana root

Science.gov (United States)

Xu, Lina

2018-02-01

CuO NPs, the size ranging from 20 to 80 nm were used to detect the adsorption and inhibition on the Arabidopsis thaliana roots. In this study, CuO NPs were adsorbed and agglomerated on the surface of root top after exposed for 7 days. With the increasing of CuO NPs concentrations, CuO NPs also adsorbed on the meristernatic zone. The growth of Arabidopsis thaliana lateral roots were also inhibited by CuO NPs exposure. The Inhibition were concentration dependent. The number of root top were 246, 188 and 123 per Arabidopsis thaliana, respectively. The number of root tops after CuO NPs exposure were significantly decreased compared with control groups. This results suggested the phytotoxicity of CuO NPs on Arabidopsis thaliana roots.

Photosynthetic pigments of oceanic Chlorophyta belonging to prasinophytes clade VII.

Science.gov (United States)

Lopes Dos Santos, Adriana; Gourvil, Priscillia; Rodríguez, Francisco; Garrido, José Luis; Vaulot, Daniel

2016-02-01

The ecological importance and diversity of pico/nanoplanktonic algae remains poorly studied in marine waters, in part because many are tiny and without distinctive morphological features. Amongst green algae, Mamiellophyceae such as Micromonas or Bathycoccus are dominant in coastal waters while prasinophytes clade VII, yet not formerly described, appear to be major players in open oceanic waters. The pigment composition of 14 strains representative of different subclades of clade VII was analyzed using a method that improves the separation of loroxanthin and neoxanthin. All the prasinophytes clade VII analyzed here showed a pigment composition similar to that previously reported for RCC287 corresponding to pigment group prasino-2A. However, we detected in addition astaxanthin for which it is the first report in prasinophytes. Among the strains analyzed, the pigment signature is qualitatively similar within subclades A and B. By contrast, RCC3402 from subclade C (Picocystis) lacks loroxanthin, astaxanthin, and antheraxanthin but contains alloxanthin, diatoxanthin, and monadoxanthin that are usually found in diatoms or cryptophytes. For subclades A and B, loroxanthin was lowest at highest light irradiance suggesting a light-harvesting role of this pigment in clade VII as in Tetraselmis. © 2015 Phycological Society of America.

Extraction of fungal polyketide pigments using ionic liquids.

OpenAIRE

Lebeau , Juliana ,; Venkatachalam , Mekala; Fouillaud , Mireille; Dufossé , Laurent; Caro , Yanis

2016-01-01

Poster communication, 8th International Conference of Pigments in Food, “Coloured foods for health benefits”, Cluj-Napoca, Romania, June 28 - July 01, 2016.; International audience; Filamentous fungi have been widely recognized as promising sources of various types ofbiomolecules and are therefore highly investigated. The production of fungal pigments is oneintensively studied domain in order to respond to the growing demand for natural colorants assubstitutes to synthetic dyes used in food, ...

Variation of Synechococcus Pigment Genetic Diversity Along Two Turbidity Gradients in the China Seas.

Science.gov (United States)

Xia, Xiaomin; Liu, Hongbin; Choi, Donghan; Noh, Jae Hoon

2018-01-01

Synechococcus are important and widely distributed picocyanobacteria that encompass a high pigment diversity. In this study, we developed a primer set (peBF/peAR) for amplifying the cpeBA operon sequence from Synechococcus genomic DNA to study Synechococcus pigment diversity along two turbidity gradients in the China seas. Our data revealed that all previously reported pigment types occurred in the South (SCS) and East (ECS) China Seas. In addition, a novel pigment genetic type (type 3f), represented by the high phycourobilin Synechococcus sp. strain KORDI-100 (Exc495:545 = 2.35), was detected. This pigment genetic type differs from the 3c/3d types not only for a very high PUB/PEB ratio but also for a different intergenic spacer sequence and gene organization of the phycobilisome. Synechococcus of different pigment types exhibited clear niche differentiation. Type 2 dominated in the coastal waters, whereas type 3c/3d and 3f were predominant in oceanic waters of the SCS in summer. In the ECS, however, type 3a was the major pigment type throughout the transect. We suggest that in marine environment, various pigment types often co-occur but with one type dominant and PUB/PEB ratio is related to geographic distribution of Synechococcus pigment types. The two marginal seas of China have markedly different Synechococcus pigment compositions.

Nanoscale Coloristic Pigments: Upper Limits on Releases from Pigmented Plastic during Environmental Aging, In Food Contact, and by Leaching

DEFF Research Database (Denmark)

Neubauer, Nicole; Scifo, Lorette; Navratilova, Jana

2017-01-01

The life cycle of nanoscale pigments in plastics may cause environmental or human exposure by various release scenarios. We investigated spontaneous and induced release with mechanical stress during/after simulated sunlight and rain degradation of polyethylene (PE) with organic and inorganic pigm...... investigated scenarios, with upper limits of 10 mg/m2 or 1600 particles/mL. This is the first holistic confirmation that pigment nanomaterials remain strongly contained in a plastic that has low diffusion and high persistence such as the polyolefin High Density Polyethylene (HDPE)....

Estimating water stressed dwarf green bean pigment concentration through hyperspectral indices