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141.
Rubia austrozhejiangensis Z. P. Lei, Y. Y. Zhou & R. W. Wang, a new species of Rubiaceae from China, is described and illustrated. The new species is similar to R. ovatifolia Z. Ying Zhang and R. argyi (H. Lév. & Vaniot) H. Hara ex Lauener, but differs from the former in having stems and branches cylindrical, not quadrate‐angled, long‐ovate to ovate‐lanceolate leaf blades, many‐flowered inflorescence, and smaller mericarps, 3–4 mm in diameter. In R. ovatifolia, stems and branches are quadrate‐angled, leaf blades ovate, ovate‐cordate to rounded cordate, and the inflorescences are sparsely flowered. Compared to R. argyi, the new species has cylindrical, not quadrate‐angled stems and branches, leaf blades that are long‐ovate to ovate‐lanceolate, 3–5‐veined, and slightly reflexed corolla lobes. In R. argyi, stems and branches are quadrate‐angled or winged, the corolla lobes are spreading, and the mericarps are 5–7 mm in diameter. 相似文献
142.
Potentilla jiaozishanensis, a distinct new species of Rosaceae from Yunnan, China, is described and illustrated. Morphologically, it is closely related to P. stenophylla var. stenophylla but clearly differs from the latter by its bidentate leaflets, lanceolate epicalyx‐segments that are longer than the sepals, villose ovaries and achenes. Moreover, the pollen grains of P. jiaozishanensis are markedly different from those of P. stenophylla var. stenophylla in size and shape. The newly described species is endemic to the Jiaozishan Mountains, southwest China. 相似文献
143.
Rong Wang Barbara C. McGrath Richard F. Kopp Michael W. Roe Xin Tang Gong Chen Douglas R. Cavener 《The Journal of biological chemistry》2013,288(47):33824-33836
Protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) (EIF2AK3) is essential for normal development and function of the insulin-secreting β-cell. Although genetic ablation of PERK in β-cells results in permanent neonatal diabetes in humans and mice, the underlying mechanisms remain unclear. Here, we used a newly developed and highly specific inhibitor of PERK to determine the immediate effects of acute ablation of PERK activity. We found that inhibition of PERK in human and rodent β-cells causes a rapid inhibition of secretagogue-stimulated subcellular Ca2+ signaling and insulin secretion. These dysfunctions stem from alterations in store-operated Ca2+ entry and sarcoplasmic endoplasmic reticulum Ca2+-ATPase activity. We also found that PERK regulates calcineurin, and pharmacological inhibition of calcineurin results in similar defects on stimulus-secretion coupling. Our findings suggest that interplay between calcineurin and PERK regulates β-cell Ca2+ signaling and insulin secretion, and that loss of this interaction may have profound implications in insulin secretion defects associated with diabetes. 相似文献
144.
Liping Zhang Daiming Jiang Jianlei Pang Rong Chen Xianghong Wang Daichang Yang 《Plant molecular biology》2013,83(1-2):153-161
The high accumulation of a recombinant protein in rice endosperm causes endoplasmic reticulum (ER) stress and in turn dramatically affects endogenous storage protein expression, protein body morphology and seed phenotype. To elucidate the molecular mechanisms underlying these changes in transgenic rice seeds, we analyzed the expression profiles of endogenous storage proteins, ER stress-related and programmed cell death (PCD)-related genes in transgenic lines with different levels of Oryza sativa recombinant alpha antitrypsin (OsrAAT) expression. The results indicated that OsrAAT expression induced the ER stress and that the strength of the ER stress was dependent on OsrAAT expression levels. It in turn induced upregulation of the expression of the ER stress response genes and downregulation of the expression of the endogenous storage protein genes in rice endosperm. Further experiments showed that the ER stress response upregulated the expression of PCD-related genes to disturb the rice endosperm development and induced pre-mature PCD. As consequence, it resulted in decrease of grain weight and size. The mechanisms for the detriment seed phenotype in transgenic lines with high accumulation of the recombinant protein were elucidated. 相似文献
145.
Jinfei Yan Rubin Cheng Xiangzhi Lin Song You Ke Li Hui Rong Yong Ma 《Applied microbiology and biotechnology》2013,97(5):1933-1939
High acetate accumulation was produced during glucose fermentation in high cell density cultures, which is harmful to cell growth. In order to reduce the negative impact of acetate accumulation on the fermentation products, we introduced the Escherichia coli acetyl-CoA synthetase (ACS) gene into the marine microalga Schizochytrium sp. TIO1101, generating genetically modified ACS transformants. The results of PCR and blotting analyses showed that the exogenous ACS gene was incorporated into the genome and successfully expressed. The engineered Schizochytrium increased the pH value and reduced the acetate concentration in the final fermentation medium significantly. Furthermore, the ACS transformants exhibited faster growth and glucose consumption rates than the wild-type strain. The biomass and fatty acid proportion of ACS transformants increased by 29.9 and 11.3 %, respectively. Taken together, the data suggest that ACS overexpression in Schizochytrium might improve the utilization of carbon resource and decrease the production of acetate byproduct. These results demonstrate that application of ACS in metabolic genetic engineering could improve the properties of Schizochytrium significantly. 相似文献
146.
147.
Hui Zhao Hao-Yang Li Jian-Feng Han Yong-Qiang Deng Yue-Xiang Li Shun-Ya Zhu Ya-Ling He E-De Qin Rong Chen Cheng-Feng Qin 《Applied microbiology and biotechnology》2013,97(24):10445-10452
Hand, foot, and mouth disease (HFMD) has caused significant morbidity and mortality in the Asia-Pacific regions, particularly in infants and young children. Coxsackievirus A16 (CA16) represents one of the major causative agents for HFMD, and the development of a safe and effective vaccine preventing CA16 infections has become a public health priority. In this study, we have developed a yeast system for the production of virus-like particles (VLPs) for CA16 by co-expressing P1 and 3CD of CA16 in Saccharomyces cerevisiae. These VLPs exhibit similarity in both protein composition and morphology as empty particles from CA16-infected cells. Immunization with CA16 VLPs in mice potently induced CA16-specific IgG and neutralization antibodies in a dose-dependent manner. IgG subclass isotyping revealed that IgG1 and lgG2b were dominantly induced by VLPs. Meanwhile, cytokine profiling demonstrated that immunization with VLPs significantly induced the secretion of IFN-γ, indicating potent cellular immune response. Furthermore, in vivo challenge experiments showed that passive immunization with anti-VLPs sera conferred full protection against lethal CA16 challenge in neonate mice. Taken together, our data demonstrated that VLPs produced in yeast might have the potential to be further developed as a vaccine candidate against HFMD. 相似文献
148.
Rakesh Santhanam Xiaoying Rong Ying Huang Barbara A. Andrews Juan A. Asenjo Michael Goodfellow 《Antonie van Leeuwenhoek》2013,103(2):367-373
A Streptomyces strain isolated from a hyper-arid Atacama Desert soil was characterised using a polyphasic taxonomic approach. The strain, designated C2T, had chemical and morphological properties typical of the genus Streptomyces. The isolate formed a branch in the Streptomyces 16S rRNA gene tree together with the type strain of Streptomyces chromofuscus and was also loosely related to Streptomyces fragilis NRRL 2424T. DNA:DNA relatedness values between the isolate and its two phylogenetic neighbours showed that it formed a distinct genomic species. The strain was readily distinguished from these organisms using a combination of morphological and phenotypic data. Based on the genotypic and phenotypic results, isolate C2T represents a novel species in the genus Streptomyces, for which the name Streptomyces bullii sp. nov. is proposed. The type strain is C2T (=CGMCC 4.7019T = KACC 15426T). 相似文献
149.
Yaou Shen Zhou Jiang Sifen Lu Haijian Lin Shibin Gao Huanwei Peng Guangsheng Yuan Li Liu Zhiming Zhang Maojun Zhao Tingzhao Rong Guangtang Pan 《Biochemical and biophysical research communications》2013
Genetic transformation of maize is highly dependent on the development of embryonic calli from the dedifferentiated immature embryo. To better understand the regulatory mechanism of immature embryo dedifferentiation, we generated four small RNA and degradome libraries from samples representing the major stages of dedifferentiation. More than 186 million raw reads of small RNA and degradome sequence data were generated. We detected 102 known miRNAs belonging to 23 miRNA families. In total, we identified 51, 70 and 63 differentially expressed miRNAs (DEMs) in the stage I, II, III samples, respectively, compared to the control. However, only 6 miRNAs were continually up-regulated by more than fivefold throughout the process of dedifferentiation. A total of 87 genes were identified as the targets of 21 DEM families. This group of targets was enriched in members of four significant pathways including plant hormone signal transduction, antigen processing and presentation, ECM-receptor interaction, and alpha-linolenic acid metabolism. The hormone signal transduction pathway appeared to be particularly significant, involving 21 of the targets. While the targets of the most significant DEMs have been proved to play essential roles in cell dedifferentiation. Our results provide important information regarding the regulatory networks that control immature embryo dedifferentiation in maize. 相似文献
150.
A sensitive chronocoulometric aptasensor for the detection of thrombin has been developed based on gold nanoparticle amplification. The functional gold nanoparticles, loaded with link DNA (LDNA) and report DNA (RDNA), were immobilized on an electrode by thrombin aptamers performing as a recognition element and capture probe. LDNA was complementary to the thrombin aptamers and RDNA was noncomplementary, but could combine with [Ru(NH3)6]3+ (RuHex) cations. Electrochemical signals obtained by RuHex that bound quantitatively to the negatively charged phosphate backbone of DNA via electrostatic interactions were measured by chronocoulometry. In the presence of thrombin, the combination of thrombin and thrombin aptamers and the release of the functional gold nanoparticles could induce a significant decrease in chronocoulometric signal. The incorporation of gold nanoparticles in the chronocoulometric aptasensor significantly enhanced the sensitivity. The performance of the aptasensor was further increased by the optimization of the surface density of aptamers. Under optimum conditions, the chronocoulometric aptasensor exhibited a wide linear response range of 0.1–18.5 nM with a detection limit of 30 pM. The results demonstrated that this nanoparticle-based amplification strategy offers a simple and effective approach to detect thrombin. 相似文献