2,590 research outputs found
Zyxin is a novel interacting partner for SIRT1
<p>Abstract</p> <p>Background</p> <p>SIRT1 is a mammalian homologue of NAD+-dependent deacetylase sirtuin family. It regulates longevity in several model organisms and is involved with cell survival, differentiation, metabolism among other processes in mammalian cells. SIRT1 modulates functions of various key targets via deacetylation. Recent studies have revealed SIRT1 protects neurons from axonal degeneration or neurodegeneration. Further, SIRT1 null mice exhibit growth retardation and developmental defects, suggesting its critical roles in neurons and development.</p> <p>Results</p> <p>To identify novel binding partners for SIRT1 in the central nervous system, we performed yeast two-hybrid screening on human fetal brain cDNA library and found that zyxin is a possible binding partner. SIRT1 and zyxin transcript were both preferentially expressed in developmental mouse brain. Zyxin accumulates in the nucleus where it is co-localized with SIRT1 after treatment with leptomycin B in COS-7 cells. Furthermore, SIRT1 deacetylates zyxin, suggesting SIRT1 could interact with nuclear-accumulated zyxin and modulate its function through deacetylation.</p> <p>Conclusion</p> <p>Zyxin could be a novel interacting partner of SIRT1. Zyxin is an adaptor protein at focal adhesion plaque, regulating cytoskeletal dynamics and signal transduction to convey signal from the ECM (extracellular matrix) to the nucleus. Our results raise the possibility that SIRT1 regulates signal transmission from ECM to the nucleus by modulating the functions of zyxin via deacetylation.</p
Efficient synthesis of biazoles by aerobic oxidative homocoupling of azoles catalyzed by a copper(I)/2-pyridonate catalytic system.
A highly efficient and convenient CuCl/2-pyridonate catalytic system for oxidative homocoupling of azoles affording a biazole product has been developed. With this system, a variety of biazoles have been effectively synthesized in good to excellent yields in the presence of a very small amount of copper catalyst (1.0 mol%). It was feasible to employ air as a green oxidant
Effect of Air or Medium Temperature on Occurrence of Leaf-yellow-spot in Chrysanthemum 'Seikou-no-makoto'
Leaf-yellow-spot, a physiological abnormality occurring in leaves of several chrysanthemum (Chrysanthemum x morifolium) cultivars is a very serious production problem in Japan. High temperature or high irradiation are possible physiological factors, which may lead to leaf-yellow-spot. In the present study, effects of air or medium temperature on the occurrence of leaf-yellow-spot in 'Seikou-nomakoto' were investigated. The nodal position with spotted leaves and rate of leaf-yellow-spot increased
with increasing day/night temperature. The nodal position with spotted leaves and rate of leaf-yellow-spot of plants grown on 30°C night air temperature were smaller than those grown on 25°C or ambient night air temperature. The days to first occurrence of leaf-yellow-spot showed no differences among medium temperatures. As occurrence of leaf-yellow-spot was not affected by root zone temperature, we recognized that occurrence of leaf-yellow-spot was promoted by high temperature or solar radiation on shoot, especially leaf. Occurrence of leaf-yellow-spot was reduced by long period high temperature and/or high solar radiation as plant growth reduced. Therefore, we thought that occurrence of leaf-yellow-spot was promoted by environmental condition as plant growth would promote.キク(Chrysanthemum × morifolium)‘精興の誠’の葉身で発生する黄斑に及ぼす気温および培地温度の影響を調査した.昼夜温を40/30℃,35/25℃,なりゆきの3区で栽培した場合,昼夜温が高いほど生育は抑制され,黄斑の発生は早くなったが,黄斑発生度は40/30℃区と比較してなりゆき区で高くなる傾向がみられた.夜温を30℃,25℃となりゆき区で栽培した場合,黄斑発生度は30℃区と比較してなりゆき区で有意な差がみられた.生育が抑制されるほどの長期間の強光や高温は黄斑発生を抑制させたことから,生育が旺盛な環境条件における外的要因により黄斑発生は助長されると考えられた.地下部の温度は黄斑発生に影響しなかったことから黄斑発生は地上部,特に葉身部位の高温により助長されることが明らかになった
A class of nowhere differentiable functions satisfying some concavity-type estimate
We introduce and investigate a class P of continuous and periodic functions on R. The class P is defined so that second-order central differences of a function satisfy some concavity-type estimate. Although this definition seems to be independent of nowhere differentiable character, it turns out that each function in P is nowhere differentiable. The class P naturally appears from both a geometrical viewpoint and an analytic viewpoint. In fact, we prove that a function belongs to P if and only if some geometrical inequality holds for a family of parabolas with vertexes on this function. As its application, we study the behavior of the Hamilton–Jacobi flow starting from a function in P. A connection between P and some functional series is also investigated. In terms of second-order central differences, we give a necessary and sufficient condition so that a function given by the series belongs to P. This enables us to construct a large number of examples of functions in P through an explicit formula
MODELING AND SIMULATION OF BIOREMEDIATION BY PHENOL-DEGRADING BACTERIA FOR TCE-CONTAMINATED GROUNDWATER
Joint Research on Environmental Science and Technology for the Eart
Searching for Diffuse Nonthermal X-Rays from the Superbubbles N11 and N51D in the Large Magellanic Cloud
We report on observations of the superbubbles (SBs) N11 and N51D in the Large
Magellanic Cloud (LMC) with Suzaku and XMM-Newton. The interior of both SBs
exhibits diffuse X-ray emission, which is well represented by thin thermal
plasma models with a temperature of 0.2-0.3keV. The presence of nonthermal
emission, claimed in previous works, is much less evident in our careful
investigation. The 3-sigma upper limits of 2-10keV flux are
3.6*10^{-14}ergs/cm^2/s and 4.7*10^{-14}ergs/cm^2/s for N11 and N51D,
respectively. The previous claims of the detection of nonthermal emission are
probably due to the inaccurate estimation of the non X-ray background. We
conclude that no credible nonthermal emission has been detected from the SBs in
the LMC, with the exception of 30 Dor C.Comment: 9 pages, accepted for publication in ApJ
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