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1.
The septins FaCdc3 and FaCdc12 are required for cytokinesis and affect asexual and sexual development,lipid metabolism and virulence in Fusarium asiaticum 下载免费PDF全文
Yu Zhang Tao Gao Wenyong Shao Zhitian Zheng Mingguo Zhou Changjun Chen 《Molecular Plant Pathology》2017,18(9):1282-1294
Septins are a highly conserved family of GTP‐binding proteins that contribute to many cellular and metabolic functions, including cell polarity, cytokinesis, cell morphogenesis and pathogenesis. In this study, we characterized the septins FaCdc3 and FaCdc12 in the filamentous fungus Fusarium asiaticum. The functions of FaCdc3 and FaCdc12 were evaluated by constructing deletion mutants of FaCdc3 and FaCdc12, designated ΔFaCdc3‐5 and ΔFaCdc12‐71, respectively. The deletion mutants exhibited a reduced rate of mycelial growth, increased aerial hyphae formation, irregularly shaped hyphae, reduced conidiation and a lack of sexual reproduction in wheat kernels. Histochemical analysis revealed that the conidia and hyphae of ΔFaCdc3‐5 and ΔFaCdc12‐71 formed large lipid droplets (LDs). ΔFaCdc3‐5 and ΔFaCdc12‐71 also exhibited increased resistance to agents that induce osmotic stress and damage the cell membrane and cell wall. In addition, the hyphae and conidia of the two mutants formed fewer septa than those of the wild‐type and exhibited aberrant nuclear distribution. Pathogenicity assays showed that ΔFaCdc3‐5 and ΔFaCdc12‐71 exhibited reduced virulence on wheat spikelets, which was indirectly correlated with a reduced level of deoxynivalenol accumulation. All of these defects were restored by genetic complementation of the two mutants with the parental FaCdc3 and FaCdc12. These results indicate that FaCdc3 and FaCdc12 play a critical role in various cellular processes in F. asiaticum. 相似文献
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Spectroscopic and in silico study of binding mechanism of cynidine‐3‐O‐glucoside with human serum albumin and glycated human serum albumin 下载免费PDF全文
The drug–serum albumin interaction plays a dominant role in drug efficacy and disposition. The glycation of serum albumin that occurs during diabetes may affect its drug‐binding properties in vivo. In order to evaluate the interactivity characteristics of cyanidin‐3‐O‐glucoside (C3G) with human serum albumin (HSA) and glycated human serum albumin (gHSA), this study was undertaken using multiple spectroscopic techniques and molecular modeling analysis. Time‐resolved fluorescence and the thermodynamic parameters indicated that the quenching mechanism was static quenching, and hydrogen bonding and Van der Waals force were the main forces. The protein fluorescence could be quenched by C3G, whereas the polarity of the fluorophore was not obviously changed. C3G significantly altered the secondary structure of the proteins. Furthermore, the interaction force that existed in the HSA–C3G system was greater than that in the gHSA–C3G system. Fluorescence excitation emission matrix spectra, red edge excitation shift, Fourier transform infrared spectroscopy and circular dichroism spectra provided further evidence that glycation could inhibit the binding between C3G and proteins. In addition, molecular modeling analysis supported the experimental results. The results provided more details for the application of C3G in the treatment of diabetes. 相似文献
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In Situ,Fast, High‐Temperature Synthesis of Nickel Nanoparticles in Reduced Graphene Oxide Matrix 下载免费PDF全文
Yiju Li Yanan Chen Anmin Nie Aijiang Lu Rohit Jiji Jacob Tingting Gao Jianwei Song Jiaqi Dai Jiayu Wan Glenn Pastel Michael R. Zachariah Reza Shahbazian Yassar Liangbing Hu 《Liver Transplantation》2017,7(11)
For the first time, a fast heating–cooling process is reported for the synthesis of carbon‐coated nickel (Ni) nanoparticles on a reduced graphene oxide (RGO) matrix (nano‐Ni@C/RGO) as a high‐performance H2O2 fuel catalyst. The Joule heating temperature can reach up to ≈2400 K and the heating time can be less than 0.1 s. Ni microparticles with an average diameter of 2 µm can be directly converted into nanoparticles with an average diameter of 75 nm. The Ni nanoparticles embedded in RGO are evaluated for electro‐oxidation performance as a H2O2 fuel in a direct peroxide–peroxide fuel cell, which exhibits an electro‐oxidation current density of 602 mA cm?2 at 0.2 V (vs Ag/AgCl), ≈150 times higher than the original Ni microparticles embedded in the RGO matrix (micro‐Ni/RGO). The high‐temperature, fast Joule heating process also leads to a 4–5 nm conformal carbon coating on the surface of the Ni nanoparticles, which anchors them to the RGO nanosheets and leads to an excellent catalytic stability. The newly developed nano‐Ni@C/RGO composites by Joule heating hold great promise for a range of emerging energy applications, including the advanced anode materials of fuel cells. 相似文献
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Merkel cell tumor is an unusual, aggressive malignancy of skin that has been considered to be derived from cutaneous Merkel cells. We are reporting a case of Merkel cell tumor overlying the left scapula with metastases to the thoracic spine and pleura. The tumor was found incidentally in a 23-year-old pregnant black woman. The tumor recurred locally 5 months after initial wide excision. Subsequently, a second wide excision of the recurrent tumor with ipsilateral axillary dissection was performed. The course of the disease was complicated by local recurrence and formation of distant metastases to pleura and spine. At the end-stage of the disease, the patient was found to have a cardiac murmur, and echocardiography revealed a mass in the anterior wall of the right ventricle that was suspicious for a metastatic lesion. The patient expired from extensive distant metastases 23 months after diagnosis. 相似文献
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p-Coumarate 3-hydroxylase (C3H) is a rate-limiting enzyme involved in monolignol biosynthesis. The full-length cDNA from Ginkgo biloba and genomic DNA sequence encoding C3H (designated as GbC3H) were cloned and characterized for the first time by rapid amplification of cDNA ends technique. The full-length cDNA of
GbC3H was of 1860 bp containing a 1527 bp open reading frame encoding a cytochrome P450 protein of 508 amino acids with a calculated
mol wt of 57.46 kD and an isoelectric point of 7.09. Two introns were present in the GbC3H gene. Comparative and bioinformatic analyses revealed that GbC3H had close similarity with C3Hs from other species and contained
a conserved cytochrome P450 cysteine heme-iron ligand signature. Phylogenetic analysis indicated that GbC3H shared a common
evolutionary origin based on sequence and had the closest relationship to C3H from gymnosperm species. Southern blot analysis
indicated that GbC3H belonged to a small-gene family. Tissue expression pattern analysis revealed the highest expression of GbC3H in roots followed by leaves, and no expression was detected in stems. Only a few proteins of this class have been found,
so the cloning and characterization of GbC3H will be useful in understanding the role of C3Hs in the lignin biosynthesis at the molecular level.
This text was submitted by the authors in English. 相似文献