87 research outputs found
Maize Provitamin A Carotenoids, Current Resources, and Future Metabolic Engineering Challenges
Vitamin A deficiency is a serious global health problem that can be alleviated by improved nutrition. Development of cereal crops with increased provitamin A carotenoids can provide a sustainable solution to eliminating vitamin A deficiency worldwide. Maize is a model for cereals and a major staple carbohydrate source. Here, we discuss maize carotenogenesis with regard to pathway regulation, available resources, and current knowledge for improving carotenoid content and levels of provitamin A carotenoids in edible maize endosperm. This knowledge will be applied to improve the nutritional composition of related Poaceae crops. We discuss opportunities and challenges for optimizing provitamin A carotenoid biofortification of cereal food crops
A novel, on-line bioinformatics exercise in genomics
The teaching objective of the āFunctional Genomics Labā is to engage the students by having them incorporate benchwork with web-based technology and analyse data in a biological context. The Functional Genomics practical involves sequencing and analysing an Arabidopsis gene. The on-line component introduces the undergraduates to a number of general and plant-specific databases, bioinformatics principles and tools. The practical is run over several sessions. The first two involve extracting and sequencing DNA to identify an āunknownā gene. During the third session students analyse their sequence to predict a function and perform hypothetical experiments to test their hypotheses. Online exercises include PCR and RNAi vector design, microarray and promoter analysis using general and plant specific web-based tools
Regulation of Carotenoid Composition and Shoot Branching in Arabidopsis by a Chromatin Modifying Histone Methyltransferase, SDG8
Carotenoid pigments are critical for plant survival, and carotenoid composition is tuned to the developmental stage, tissue, and to environmental stimuli. We report the cloning of the CAROTENOID CHLOROPLAST REGULATORY1 (CCR1) gene. The ccr1 mutant has increased shoot branching and altered carotenoid composition, namely, reduced lutein in leaves and accumulation of cis-carotenes in dark-grown seedlings. The CCR1 gene was previously isolated as EARLY FLOWERING IN SHORT DAYS and encodes a histone methyltransferase (SET DOMAIN GROUP 8) that methylates histone H3 on Lys 4 and/or 36 (H3K4 and H3K36). ccr1 plants show reduced trimethyl-H3K4 and increased dimethyl-H3K4 surrounding the CAROTENOID ISOMERASE (CRTISO) translation start site, which correlates with low levels of CRTISO mRNA. Microarrays of ccr1 revealed the downregulation of 85 genes, including CRTISO and genes associated with signaling and development, and upregulation of just 28 genes. The reduction in CRTISO transcript abundance explains the altered carotenoid profile. The changes in shoot branching are additive with more axillary branching mutants, but the altered carotenoid profile may partially affect shoot branching, potentially by perturbed biosynthesis of the carotenoid substrates of strigolactones. These results are consistent with SDG8 regulating shoot meristem activity and carotenoid biosynthesis by modifying the chromatin surrounding key genes, including CRTISO. Thus, the level of lutein, the most abundant carotenoid in higher plants that is critical for photosynthesis and photoprotection, appears to be regulated by a chromatin modifying enzyme in Arabidopsis thaliana
Sensitive germanium thermistors for cryogenic thermal detector of Tokyo dark matter search programme
Sensitive n-type and p-type germanium thermistors were fabricated by the melt
doping technique and by the neutron transmutation doping (NTD) technique,
respectively, aiming at a use for the cryogenic thermal detector, or bolometer
of Tokyo dark matter search programme. We report on the measurements of the
sensitivities of these thermistors. In particular, the p-type thermistors are
sensitive enough to scale up our existing prototype LiF bolometer and realize a
multiple array of the bolometers with the total absorber mass of about 1\,kg.Comment: 14 pages, revtex, with 4 postscript figures appended (uuencoded
Role of the Arabidopsis PIN6 auxin transporter in auxin homeostasis and auxin-mediated development
Plant-specific PIN-formed (PIN) efflux transporters for the plant hormone auxin are required for tissue-specific directional auxin transport and cellular auxin homeostasis. The Arabidopsis PIN protein family has been shown to play important roles in developmental processes such as embryogenesis, organogenesis, vascular tissue differentiation, root meristem patterning and tropic growth. Here we analyzed roles of the less characterised Arabidopsis PIN6 auxin transporter. PIN6 is auxin-inducible and is expressed during multiple auxināregulated developmental processes. Loss of pin6 function interfered with primary root growth and lateral root development. Misexpression of PIN6 affected auxin transport and interfered with auxin homeostasis in other growth processes such as shoot apical dominance, lateral root primordia development, adventitious root formation, root hair outgrowth and root waving. These changes in auxin-regulated growth correlated with a reduction in total auxin transport as well as with an altered activity of DR5-GUS auxin response reporter. Overall, the data indicate that PIN6 regulates auxin homeostasis during plant development.Christopher I. Cazzonelli, Marleen Vanstraelen, Sibu Simon, Kuide Yin, Ashley Carron-Arthur, Nazia Nisar, Gauri Tarle, Abby J. CuttrissĀ¤, Iain R. Searle, Eva Benkova, Ulrike Mathesius, Josette Masle, JiÅĆ Friml, Barry J. Pogso
Howard E. Cuttriss
"[30806] L.A.C. Howard. E. Cuttriss. (Peter) 2. Sqdn. R.A.A.F. Darwin Feb 11th 1942 Batchelor November 1942 to 1943".[30806] Leading Aircraftman Howard E. Cuttriss (Peter). 2 Squadron, Royal Australian Air Force. Darwin, February 11th 1942. Batchelor, November 1942 to 1943
Brass Band Music in the Cook Islands: A Biographical Account
no abstract
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JSTOR link to article (restricted access) https://www.jstor.org/stable/2682853
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