236 research outputs found
Identification of Chalcones and their Contribution to Yellow Coloration in Dahlia (Dahlia variabilis) Ray Florets
Yellow color in dahlia flowers is conferred from chalcones, butein and isoliquiritigenin. The color intensity of yellow dahlia cultivars is diverse, but a detailed study on this has not yet been performed. In this study, we first identified structures of flavonoids by nuclear magnetic resonance imaging in ray florets of the red-white bicolor ‘Shukuhai’, which contains chalcones, flavones and anthocyanins. Four anthocyanins, four flavone derivatives, five isoliquiritigenin derivatives and five butein derivatives were identified. Among the identified compounds, butein 4'-malonylsophoroside is considered to be the final product for butein derivatives and the presence of chalcone 4'-glucosyltransferase, chalcone 4'-glucoside glucosyltransferase, and chalcone 4'-glucoside malonyltransferase for isoliquiritigenin and butein modification was predicted. Also, the biosynthetic pathway of butein and isoliquiritigenin derivatives in dahlia with butein 4'-malonylsophoroside as the final product was predicted from the identified compounds. Next, we used nine yellow cultivars and lines with different color intensities and analyzed the correlation between the b* value, an indicator of yellow color, and level of chalcones. There was no difference in the presence or absence of major peaks among the cultivars and lines. Peak area per fresh weight measured by HPLC was high in butein 4'-malonylglucoside, butein 4'-sophoroside and isoliquiritigenin 4'-malonylglucoside, suggesting these three compounds were accumulated abundantly. Among the identified chalcones, the highest correlation coefficient was detected between the b* value and butein 4'-malonylglucoside (r = 0.86), butein 4'-sophoroside (r = 0.82) or isoliquiritigenin 4'-malonylglucoside (r = 0.76). These results suggest that these three chalcones confer yellow color in dahlia ray florets. The findings in this study will contribute not only to efforts at breeding new yellow dahlia cultivars, but also to molecular breeding of yellow flowers in other species by introducing the butein biosynthetic pathway
Lack of association of Toll-like receptor 9 gene polymorphism with Behcet's disease in Japanese patients
The definitive version is available at www.blackwell-synergy.com.ArticleTISSUE ANTIGENS. 70(1-5) 423-426 (2007)journal articl
Intrinsic insulating transport characteristics in low-carrier density EuCd2As2 films
Searching for an ideal magnetic Weyl semimetal hosting only a single pair of
Weyl points has been a focal point for systematic clarification of its unique
magnetotransport derived from the interplay between topology and magnetization.
Among the candidates, triangular-lattice antiferromagnet EuCdAs has
been attracting special attention due to the prediction of the ideal Weyl
semimetal phase in the ferromagnetic state, however, transport properties of
low-carrier density samples have remained elusive. Here we report molecular
beam epitaxy growth of EuCdAs films, achieving low-hole density in the
range of - cm at low temperature. Transport
measurements of such low-carrier density films reveal an insulating behavior
with an activation gap of about 200 meV, which persists even in the
field-induced ferromagnetic state. Our work provides an important experimental
clue that EuCdAs is intrinsically insulating, contrary to the previous
prediction.Comment: 12 pages, 3 figure
Maximizing intrinsic anomalous Hall effect by controlling the Fermi level in simple Weyl semimetal films
Large intrinsic anomalous Hall effect (AHE) originating in the Berry
curvature has attracted growing attention for potential applications. Recently
proposed magnetic Weyl semimetal EuCdSb provides an
excellent platform for controlling the intrinsic AHE because it only hosts a
Weyl-points related band structure near the Fermi energy. Here we report the
fabrication of EuCdSb single-crystalline films and control
of their anomalous Hall effect by film technique. As also analyzed by
first-principles calculations of energy-dependent intrinsic anomalous Hall
conductivity, the obtained anomalous Hall effect shows a sharp peak as a
function of carrier density, demonstrating clear energy dependence of the
intrinsic AHE.Comment: 13 pages, 4 figure
Evaluation of PTPN22 polymorphisms and Vogt-Koyanagi-Harada disease in Japanese patients
Purpose: Vogt-Koyanagi-Harada (VKH) disease is an autoimmune disorder against melanocytes. Polymorphisms of the protein tyrosine phosphatase non-receptor 22 gene (PTPN22) have recently been reported to be associated with susceptibility to several autoimmune diseases. In this study, genetic susceptibility to VKH disease was investigated by screening for single nucleotide polymorphisms (SNPs) of PTPN22. Methods: A total of 167 Japanese patients with VKH disease and 188 healthy Japanese controls were genotyped by direct sequencing methods for six SNPs (rs3811021, rs1217413, rs1237682, rs3761935, rs3789608, and rs2243471) of PTPN22 including the uncoding exons. Results: The six SNPs in PTPN22 showed no significant association with susceptibility to VKH disease or its ocular, neurologic, or dermatological manifestation. Conclusions: Further studies are needed to clarify the genetic mechanisms underlying VKH disease
PSMC5, a 19S Proteasomal ATPase, Regulates Cocaine Action in the Nucleus Accumbens
ΔFosB is a stable transcription factor which accumulates in the nucleus accumbens (NAc), a key part of the brain’s reward circuitry, in response to chronic exposure to cocaine or other drugs of abuse. While ΔFosB is known to heterodimerize with a Jun family member to form an active transcription factor complex, there has not to date been an open-ended exploration of other possible binding partners for ΔFosB in the brain. Here, by use of yeast two-hybrid assays, we identify PSMC5—also known as SUG1, an ATPase-containing subunit of the 19S proteasomal complex—as a novel interacting protein with ΔFosB. We verify such interactions between endogenous ΔFosB and PSMC5 in the NAc and demonstrate that both proteins also form complexes with other chromatin regulatory proteins associated with gene activation. We go on to show that chronic cocaine increases nuclear, but not cytoplasmic, levels of PSMC5 in the NAc and that overexpression of PSMC5 in this brain region promotes the locomotor responses to cocaine. Together, these findings describe a novel mechanism that contributes to the actions of ΔFosB and, for the first time, implicates PSMC5 in cocaine-induced molecular and behavioral plasticity.National Institutes of Health (U.S.)National Institute on Drug AbuseIshibashi FoundationJapan Society for the Promotion of Science (KAKENHI 24591735)Japan Society for the Promotion of Science (KAKENHI 26290064)Japan Society for the Promotion of Science (KAKENHI 25116010
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