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951.
Eggshell strength is a crucial economic trait for table egg production. During the process of eggshell formation, uncalcified eggs are bathed in uterine fluid that plays regulatory roles in eggshell calcification. In this study, a label‐free MS‐based protein quantification technology was used to detect differences in protein abundance between eggshell matrix from strong and weak eggs (shell matrix protein from strong eggshells and shell matrix protein from weak eggshells) and between the corresponding uterine fluids bathing strong and weak eggs (uterine fluid bathing strong eggs and uterine fluid bathing weak eggs) in a chicken population. Here, we reported the first global proteomic analysis of uterine fluid. A total of 577 and 466 proteins were identified in uterine fluid and eggshell matrix, respectively. Of 447 identified proteins in uterine fluid bathing strong eggs, up to 357 (80%) proteins were in common with proteins in uterine fluid bathing weak eggs. Similarly, up to 83% (328/396) of the proteins in shell matrix protein from strong eggshells were in common with the proteins in shell matrix protein from weak eggshells. The large amount of common proteins indicated that the difference in protein abundance should play essential roles in influencing eggshell strength. Ultimately, 15 proteins mainly relating to eggshell matrix specific proteins, calcium binding and transportation, protein folding and sorting, bone development or diseases, and thyroid hormone activity were considered to have closer association with the formation of strong eggshell. 相似文献
952.
953.
954.
Jun Qian Chen-xu Liu Wu-deng Wang Jing Chen Yu-dong Li Jing-jun Xu Qian Sun 《Plasmonics (Norwell, Mass.)》2013,8(2):955-962
The optical responses of metal nanoparticles induced by subtle variations in geometry, especially by the rounding of the edges and corners, have generated great interest at present due to the requirement of fabricating refined structures of metal nanoparticles and theoretical simulations of the real particles. We study the effect of both inner and outer edge rounding on the optical properties of gold nanobox and gold nanobox dimer with small interparticle distances by using the discrete dipole approximation method. The shift of extinction peaks, the electric field distribution, and the variation of refractive index sensitivities by changing the curvature of the inner and outer edges of gold nanobox are investigated. We demonstrate that the optical properties of nanobox are more sensitive to the outer edge rounding than the inner edge rounding. By edge rounding of two very close gold nanoboxes, the blue shift of the dipolar and the quadrupolar plasmonic resonances of nanobox dimer are shown. Comparing with the inner edge rounding of nanobox dimer, we find that rounding of the outer edges causes the larger shift of the quadrupolar mode and approximate shift of the dipole mode. 相似文献
955.
Rui Zhang Zhigang Meng Tao Zhou Yong Deng Li Feng Yuan Wang Guoqing Sun Sandui Guo Maozhi Ren 《Plant signaling & behavior》2013,8(11)
FKBP12 encodes a prolyl isomerase and highly conserved in eukaryotic species. In yeasts and animals, FKBP12 can interact with rapamycin and FK506 to form rapamycin-FKBP12 and FK506-FKBP12 complex, respectively. In higher plants, FKBP12 protein lost its function to bind rapamycin and FK506. Early studies showed that yeast and human FKBP12 protein can restore the rapamycin sensitivity in Arabidopsis, but the used concentration is 100–1000 folds higher than that in yeast and animals. High concentration of drugs would increase the cost and cause the potential secondary effects on plant growth and development. Here we further discovered that BP12 plants generated in our previous study are hypersensitive to rapamycin at the concentration as low as that is effective in yeast and animals. It is surprising to observe that WT and BP12 plants are not sensitive to FK506 in normal growth condition. These findings advance the current understanding of rapamycin-TOR signaling in plants. 相似文献
956.
Kejian Wang Jiazhi Sun Shufeng Zhou Chunling Wan Shengying Qin Can Li Lin He Lun Yang 《PLoS computational biology》2013,9(11)
Small drug molecules usually bind to multiple protein targets or even unintended off-targets. Such drug promiscuity has often led to unwanted or unexplained drug reactions, resulting in side effects or drug repositioning opportunities. So it is always an important issue in pharmacology to identify potential drug-target interactions (DTI). However, DTI discovery by experiment remains a challenging task, due to high expense of time and resources. Many computational methods are therefore developed to predict DTI with high throughput biological and clinical data. Here, we initiatively demonstrate that the on-target and off-target effects could be characterized by drug-induced in vitro genomic expression changes, e.g. the data in Connectivity Map (CMap). Thus, unknown ligands of a certain target can be found from the compounds showing high gene-expression similarity to the known ligands. Then to clarify the detailed practice of CMap based DTI prediction, we objectively evaluate how well each target is characterized by CMap. The results suggest that (1) some targets are better characterized than others, so the prediction models specific to these well characterized targets would be more accurate and reliable; (2) in some cases, a family of ligands for the same target tend to interact with common off-targets, which may help increase the efficiency of DTI discovery and explain the mechanisms of complicated drug actions. In the present study, CMap expression similarity is proposed as a novel indicator of drug-target interactions. The detailed strategies of improving data quality by decreasing the batch effect and building prediction models are also effectively established. We believe the success in CMap can be further translated into other public and commercial data of genomic expression, thus increasing research productivity towards valid drug repositioning and minimal side effects. 相似文献
957.
Xue Wang Fengting Xu Jiasen Liu Bingquan Gao Yanxin Liu Yujia Zhai Jun Ma Kai Zhang Timothy S. Baker Klaus Schulten Dong Zheng Hai Pang Fei Sun 《PLoS pathogens》2013,9(1)
Rabbit hemorrhagic disease, first described in China in 1984, causes hemorrhagic necrosis of the liver. Its etiological agent, rabbit hemorrhagic disease virus (RHDV), belongs to the Lagovirus genus in the family Caliciviridae. The detailed molecular structure of any lagovirus capsid has yet to be determined. Here, we report a cryo-electron microscopic (cryoEM) reconstruction of wild-type RHDV at 6.5 Å resolution and the crystal structures of the shell (S) and protruding (P) domains of its major capsid protein, VP60, each at 2.0 Å resolution. From these data we built a complete atomic model of the RHDV capsid. VP60 has a conserved S domain and a specific P2 sub-domain that differs from those found in other caliciviruses. As seen in the shell portion of the RHDV cryoEM map, which was resolved to ∼5.5 Å, the N-terminal arm domain of VP60 folds back onto its cognate S domain. Sequence alignments of VP60 from six groups of RHDV isolates revealed seven regions of high variation that could be mapped onto the surface of the P2 sub-domain and suggested three putative pockets might be responsible for binding to histo-blood group antigens. A flexible loop in one of these regions was shown to interact with rabbit tissue cells and contains an important epitope for anti-RHDV antibody production. Our study provides a reliable, pseudo-atomic model of a Lagovirus and suggests a new candidate for an efficient vaccine that can be used to protect rabbits from RHDV infection. 相似文献
958.
Xiao Na Wang Ze Song Li Yu Ren Tao Jiang Ya Qing Wang Min Chen Jun Zhang Jian Xiu Hao Yan Bo Wang Ri Na Sha Yi Huang Xiao Liu Jing Chu Hu Guang Qing Sun Hong Gang Li Cheng Liang Xiong Jun Xie Zhi Mao Jiang Zhi Ming Cai Jun Wang Jian Wang Vicki Huff Yao Ting Gui Fei Gao 《PLoS genetics》2013,9(8)
Azoospermia is one of the major reproductive disorders which cause male infertility in humans; however, the etiology of this disease is largely unknown. In the present study, six missense mutations of WT1 gene were detected in 529 human patients with non-obstructive azoospermia (NOA), indicating a strong association between WT1 mutation and NOA. The Wilms tumor gene, Wt1, is specifically expressed in Sertoli cells (SCs) which support spermatogenesis. To examine the functions of this gene in spermatogenesis, Wt1 was deleted in adult testis using Wt1flox and Cre-ERTM mice strains. We found that inactivation of Wt1 resulted in massive germ cell death and only SCs were present in most of the seminiferous tubules which was very similar to NOA in humans. In investigating the potential mechanism for this, histological studies revealed that the blood–testis barrier (BTB) was disrupted in Wt1 deficient testes. In vitro studies demonstrated that Wt1 was essential for cell polarity maintenance in SCs. Further studies found that the expression of cell polarity associated genes (Par6b and E-cadherin) and Wnt signaling genes (Wnt4, Wnt11) were downregulated in Wt1 deficient SCs, and that the expression of Par6b and E-cadherin was regulated by Wnt4. Our findings suggest that Wt1 is important in spermatogenesis by regulating the polarity of SCs via Wnt signaling pathway and that WT1 mutation is one of the genetic causes of NOA in humans. 相似文献
959.
Guoxu Ma Haifeng Wu Jingquan Yuan Lizhen Wu Qingxia Zheng Zhaocui Sun Xiaoru Fan Hua Wei Junshan Yang Xudong Xu 《Phytochemistry letters》2013,6(1):152-155
Five phenylpropanoids including one new compound balanophonin A (1), one new natural compound balanophonin B (2) were isolated from the seeds of Lithocarpus pachylepis for the first time. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7. 相似文献
960.
Guang Sun Farrell Cahill Wayne Gulliver Yanqing Yi Yagang Xie Tracey Bridger David Pace Hongwei Zhang 《Obesity (Silver Spring, Md.)》2013,21(3):499-503