Brassinosteroid Biosynthesis Is Modulated via a Transcription Factor Cascade of COG1, PIF4, and PIF5

Wei, Zhuoyun,Yuan, Tong,Tarkowsks&#x30c,a&#x301,, Danus&#x30c,e,Kim, Jeongsik,Nam, Hong Gil,Novs&#x30c,a&#x301,r&#x30c,a&#x301,k, Onds&#x30c,a&#x301,r&#x30c,ej,He, Kai,Gou, Xiaoping,Li, Jia American Society of Plant Biologists 2017 Plant Physiology Vol.174 No.2

<P>Brassinosteroids (BRs) are essential phytohormones regulating various developmental and physiological processes during normal growth and development. cog1-3D (cogwheel1-3D) was identified as an activation-tagged genetic modifier of bri1-5, an intermediate BR receptor mutant in Arabidopsis (Arabidopsis thaliana). COG1 encodes a Dof-type transcription factor found previously to act as a negative regulator of the phytochrome signaling pathway. cog1-3D single mutants show an elongated hypocotyl phenotype under light conditions. A loss-of-function mutant or inducible expression of a dominant negative form of COG1 in the wild type results in an opposite phenotype. A BR profile assay indicated that BR levels are elevated in cog1-3D seedlings. Quantitative reverse transcription-polymerase chain reaction analyses showed that several key BR biosynthetic genes are significantly up-regulated in cog1-3D compared with those of the wild type. Two basic helix-loop-helix transcription factors, PIF4 and PIF5, were found to be transcriptionally up-regulated in cog1-3D. Genetic analysis indicated that PIF4 and PIF5 were required for COG1 to promote BR biosynthesis and hypocotyl elongation. Chromatin immunoprecipitation and electrophoretic mobility shift assays indicated that COG1 binds to the promoter regions of PIF4 and PIF5, and PIF4 and PIF5 bind to the promoter regions of key BR biosynthetic genes, such as DWF4 and BR6ox2, to directly promote their expression. These results demonstrated that COG1 regulates BR biosynthesis via up-regulating the transcription of PIF4 and PIF5.</P>

<i>Swift</i>,<i>XMM</i>-<i>Newton</i>, and<i>NuSTAR</i>Observations of PSR J2032+4127/MT91 213

Li, K. L.,Kong, A. K. H.,Tam, P. H. T.,Hou, X.,Takata, J.,Hui, and C. Y. American Astronomical Society 2017 The Astrophysical journal Vol.843 No.2

<P>We report our recent Swift, NuSTAR, and XMM-Newton X-ray and Lijiang optical observations on PSR J2032 + 4127/MT91 213, the gamma-ray binary candidate with a period of 45-50 years. The coming periastron of the system was predicted to be in 2017 November, around which high-energy flares from keV to TeV are expected. Recent studies with Chandra and Swift X-ray observations taken in 2015/2016 showed that its X-ray emission has been brighter by a factors of similar to 10 than that before 2013, probably revealing some ongoing activities between the pulsar wind and the stellar wind. Our new Swift/XRT lightcurve shows no strong evidence of a single vigorous brightening trend, but rather several strong X-ray flares on weekly to monthly timescales with a slowly brightening baseline, namely the low state. The NuSTAR and XMM-Newton observations taken during the flaring and the low states, respectively, show a denser environment and a softer power-law index during the flaring state, implying that the pulsar wind interacted with the stronger stellar winds of the companion to produce the flares. These precursors would be crucial in studying the predicted giant outburst from this extreme gamma-ray binary during the periastron passage in late 2017.</P>

Nanoscale Assembly in Biological Systems: From Neuronal Cytoskeletal Proteins to Curvature Stabilizing Lipids

Safinya, Cyrus R.,Raviv, Uri,Needleman, Daniel J.,Zidovska, Alexandra,Choi, Myung Chul,Ojeda&#x2010,Lopez, Miguel A.,Ewert, Kai K.,Li, Youli,Miller, Herbert P.,Quispe, Joel,Carragher, Bridget,Potter, WILEY‐VCH Verlag 2011 ADVANCED MATERIALS Vol.23 No.20

<P><B>Abstract</B></P><P>The review will describe experiments inspired by the rich variety of bundles and networks of interacting microtubules (MT), neurofilaments, and filamentous‐actin in neurons where the nature of the interactions, structures, and structure‐function correlations remain poorly understood. We describe how three‐dimensional (3D) MT bundles and 2D MT bundles may assemble, in cell free systems in the presence of counter‐ions, revealing structures not predicted by polyelectrolyte theories. Interestingly, experiments reveal that the neuronal protein tau, an abundant MT‐associated‐protein in axons, modulates the MT diameter providing insight for the control of geometric parameters in bio‐ nanotechnology. In another set of experiments we describe lipid‐protein‐nanotubes, and lipid nano‐ tubes and rods, resulting from membrane shape evolution processes involving protein templates and curvature stabilizing lipids. Similar membrane shape changes, occurring in cells for the purpose of specific functions, are induced by interactions between membranes and proteins. The biological materials systems described have applications in bio‐nanotechnology.</P>

Runx3 is required for the differentiation of lung epithelial cells and suppression of lung cancer

Lee, K-S,Lee, Y-S,Lee, J-M,Ito, K,Cinghu, S,Kim, J-H,Jang, J-W,Li, Y-H,Goh, Y-M,Chi, X-Z,Wee, H,Lee, H-W,Hosoya, A,Chung, J-H,Jang, J-J,Kundu, J K,Surh, Y-J,Kim, W-J,Ito, Y,Jung, H-S,Bae, S-C Macmillan Publishers Limited 2010 Oncogene Vol.29 No.23

Human lung adenocarcinoma, the most prevalent form of lung cancer, is characterized by many molecular abnormalities. K-ras mutations are associated with the initiation of lung adenocarcinomas, but K-ras-independent mechanisms may also initiate lung tumors. Here, we find that the runt-related transcription factor Runx3 is essential for normal murine lung development and is a tumor suppressor that prevents lung adenocarcinoma. Runx3−/− mice, which die soon after birth, exhibit alveolar hyperplasia. Importantly, Runx3−/− bronchioli exhibit impaired differentiation, as evidenced by the accumulation of epithelial cells containing specific markers for both alveolar (that is SP-B) and bronchiolar (that is CC10) lineages. Runx3−/− epithelial cells also express Bmi1, which supports self-renewal of stem cells. Lung adenomas spontaneously develop in aging Runx3+/− mice (∼18 months after birth) and invariably exhibit reduced levels of Runx3. As K-ras mutations are very rare in these adenomas, Runx3+/− mice provide an animal model for lung tumorigenesis that recapitulates the preneoplastic stage of human lung adenocarcinoma development, which is independent of K-Ras mutation. We conclude that Runx3 is essential for lung epithelial cell differentiation, and that downregulation of Runx3 is causally linked to the preneoplastic stage of lung adenocarcinoma.

Face changing companion of the redback millisecond pulsar PSR J1048+2339

Yap, Y. X.,Li, K. L.,Kong, A. K. H.,Takata, J.,Lee, J.,Hui, C. Y. Springer-Verlag 2019 Astronomy and astrophysics Vol.621 No.-

<P>We present optical observations of the redback millisecond pulsar PSR J1048+2339, which is a 4.66 ms radio pulsar in a compact binary with an orbital period of six hours. We obtained high-quality light curves of PSR J1048+2339 with the Lulin 1 m Telescope. The system shows two distinct six-hour orbital modulations, in which an ellipsoidal modulation changes into a sinusoidal-like profile in less than 14 days. In addition to the change, the brightness of the companion increased by one magnitude, suggesting that the latter type of modulation is caused by the pulsar wind heating of the companion and that the heating became dominant in the system. While the changes are not unexpected, such a timescale is the shortest among similar systems. We performed modeling analysis to extract the properties of the system. We obtained a derived pulsar mass of 2.1 <I>M</I>⊙ and a companion star mass of 0.4 <I>M</I>⊙ for the system. The irradiation power increased by a factor of 6 during which the pulsar wind heating dominates. We also report on the two archival <I>Chandra</I> X-ray observations and discuss several possibilities that might cause the varying heating on the companion.</P>

Polymorphism of Ghrelin Gene in Twelve Chinese Indigenous Chicken Breeds and Its Relationship with Chicken Growth Traits

C. C. Li,K. Li,J. Li,D. L. Mo,R. F. Xu,G. H. Chen,Y. Z. Qiangba,S. L. Ji,X. H. Tang,B. Fan,M. J. Zhu,T. A. Xiong,X. Guan,B. Liu 아세아·태평양축산학회 2006 Animal Bioscience Vol.19 No.2

A 2,656 bp fragment of chicken ghrelin gene was cloned and SNPs were detected by PCR-RFLP and Allele Specific PCR (ASP) in 12 Chinese indigenous chicken breeds and a commercial chicken population. The results showed that there were 23 base variations and an amino acid change (Gln->Arg) in cloned chicken ghrelin gene. Three SNPs were confirmed in 13 populations and associations between this gene and growth traits of Tibetan chicken (TC) and Recessive White chicken (RW) were investigated. The results of haplotype analysis revealed that 26 haplotype genotypes were composed of eight haplotypes. The results of x2 tests indicated that there were significant differences between genotypes or haplotype genotype frequencies in some of the breeds or sexes at 0.05 or 0.01 levels. The results of ANOVA revealed that there were significant differences between genotypes or haplotype genotypes on some growth traits of TC and RW chicken breeds at 0.05 or 0.01 levels. Multiple comparisons showed that there were significant associations between genotype CT at site 71 and some growth traits of two chicken breeds and between genotype AG at site 1,215 and body weight at 16 wk of two chicken breeds, and there was a significant association between haplotype genotype CAA/CAG and body weight and shank girth at 16 wk of two chicken breeds.

Effect of alendronate on healing of extraction sockets and healing around implants

Kim, J&#x2010,H,Park, Y&#x2010,B,Li, Z,Shim, J&#x2010,S,Moon, H&#x2010,S,Jung, H&#x2010,S,Chung, M&#x2010,K Blackwell Publishing Ltd 2011 Oral diseases Vol.17 No.7

<P><I>Oral Diseases</I> (2011) <B>17</B>, 705–711</P><P><B>Objectives: </B> The purpose of this study was to evaluate the effect of alendronates on healing of extraction sockets and healing around implants in the maxilla of rats.</P><P><B>Materials and Methods: </B> Twenty‐four Sprague–Dawley rats were used. The rats in bisphosphonate group were subcutaneously injected with alendronate (5.0 mg kg<SUP>‐‐1</SUP>) three times a week for 4 weeks. Both sides of the maxillary first molars were extracted, and customized titanium implants (Ø1.5 × 2.0 mm) were placed immediately into one side. Rats were killed at 3, 7, 14, or 28 days following surgery.</P><P><B>Results: </B> New bone formation in extraction sockets, bone area around the implant site, and bone–implant contact were not delayed in the bisphosphonate group. The tartrate‐resistant acid phosphatase positive cell count did not differ between bisphosphonate and control groups; however, empty lacunae were observed significantly more in bisphosphonate group. The differences in empty lacunae were shown at different time points between the implant sites and extraction sites: at 7 days after extraction, and at 14 and 28 days after implantation.</P><P><B>Conclusions: </B> Alendronates seemed to decrease bone resorption but not to decrease bone formation. Empty lacunae were observed significantly more at later time points in implant sites compared to extraction sockets.</P>

Ursolic acid increases the secretion of atrial natriuretic peptide in isolated perfused beating rabbit atria

Cui, H.Z.,Wen, J.F.,Choi, H.R.,Li, X.,Cho, K.W.,Kang, D.G.,Lee, H.S. North-Holland ; Elsevier Science Ltd 2011 european journal of pharmacology Vol.653 No.1

Ursolic acid is reported to have beneficial effects on the regulation of cardiovascular homeostasis. However, the effects of ursolic acid on cardiac hormone secretion are yet to be defined. The present study was designed to test the effects of ursolic acid on the secretory and contractile functions of the atria. Experiments were conducted in isolated perfused beating rabbit atria. We measured the changes in atrial dynamics, pulse pressure, stroke volume, cAMP efflux, as well as the secretion of atrial natriuretic peptide (ANP). Ursolic acid increased ANP secretion and mechanical dynamics in a concentration-dependent manner. The inhibition of L-type Ca<SUP>2+</SUP> channels with nifedipine attenuated the ursolic acid-induced increase in ANP secretion but not mechanical dynamics. The inhibition of K<SUP>+</SUP><SUB>ATP</SUB> channels with glibenclamide attenuated the ursolic acid-induced increase in ANP secretion-but not atrial dynamics-in a concentration-dependent manner. The selective Na<SUP>+</SUP>-K<SUP>+</SUP>-ATPase inhibitor ouabain blocked the ursolic acid-induced increase in atrial dynamics but not ANP secretion. These findings show that ursolic acid increases ANP secretion via its activation of K<SUP>+</SUP><SUB>ATP</SUB> channels and subsequent inhibition of Ca<SUP>2+</SUP> entry through L-type Ca<SUP>2+</SUP> channels in rabbit atria. These data also suggest that ursolic acid increases atrial dynamics via its inhibition of Na<SUP>+</SUP>-K<SUP>+</SUP>-ATPase activity.

Spectral tomographic analysis of Bremsstrahlung X-rays generated in a laser-produced plasma

Rhee, Y.J.,Nam, S.M.,Peebles, J.,Sawada, H.,Wei, M.,Vaisseau, X.,Sasaki, T.,Giuffrida, L.,Hulin, S.,Vauzour, B.,Santos, J.J.,Batani, D.,McLean, H.S.,Patel, P.K.,Li, Y.T.,Yuan, D.W.,Zhang, K.,Zhong, J. Cambridge University Press 2016 Laser and particle beams Vol.34 No.4

<B>Abstract</B><P>A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.</P>

R&D Status of High-current Accelerators at IFP

J. J. Deng,J. S. Shi,W. P. Xie,L. W. Zhang,K. Z. Zhang,S. P. Feng,J. Li,M. Wang,Y. He,L. S. Xia,Z. Y. Dai,H. T. Li,L. Wen,S. F. Chen,X. Li,Q. G. Lai,M. H. Xia,Y. C. Guan,S. Y. Song,L. Chen 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

High-current accelerators have many important applications in Z-pinches, high-power microwaves, and free electron lasers, imploding liners and radiography and so on. Research activities on Zpinches, imploding liners, radiography at the Institute of Fluid Physics (IFP) are introduced. Several main high-current accelerators developed and being developed at IFP are described, such as the Linear Induction Accelerator X-Ray Facility Upgrade (LIAXFU, 12 MeV, 2.5 kA, 90 ns), the Dragon-I linear induction accelerator (20 MeV, 2.5 kA, 60 ns), and the Primary Test Stand for Z-pinch (PTS, 10 MA, 120 ns). The design of Dragon-II linear induction accelerator (20 MeV, 2.5 kA, 3 × 60 ns) to be built will be presented briefly.