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961.
Identifying qualitative effects of different grazing types on below‐ground communities and function in a long‐term field experiment 下载免费PDF全文
Catriona A. Macdonald Michael J. Crawley Denis J. Wright Justin Kuczynski Lucinda Robinson Rob Knight Waleed Abu Al‐Soud Søren J. Sørensen Ye Deng Jizhong Zhou Brajesh K. Singh 《Environmental microbiology》2015,17(3):841-854
Herbivory is an important modulator of plant biodiversity and productivity in grasslands, but our understanding of herbivore‐induced changes on below‐ground processes and communities is limited. Using a long‐term (17 years) experimental site, we evaluated impacts of rabbit and invertebrate grazers on some soil functions involved in carbon cycling, microbial diversity, structure and functional composition. Both rabbit and invertebrate grazing impacted soil functions and microbial community structure. All functional community measures (functions, biogeochemical cycling genes, network association between different taxa) were more strongly affected by invertebrate grazers than rabbits. Furthermore, our results suggest that exclusion of invertebrate grazers decreases both microbial biomass and abundance of genes associated with key biogeochemical cycles, and could thus have long‐term consequences for ecosystem functions. The mechanism behind these impacts are likely to be driven by both direct effects of grazing altering the pattern of nutrient inputs and by indirect effects through changes in plant species composition. However, we could not entirely discount that the pesticide used to exclude invertebrates may have affected some microbial community measures. Nevertheless, our work illustrates that human activity that affects grazing intensity may affect ecosystem functioning and sustainability, as regulated by multi‐trophic interactions between above‐ and below‐ground communities. 相似文献
962.
PsMPK7, a stress‐associated mitogen‐activated protein kinase (MAPK) in Phytophthora sojae,is required for stress tolerance,reactive oxygenated species detoxification,cyst germination,sexual reproduction and infection of soybean 下载免费PDF全文
963.
Elena M. Pugacheva Samuel Rivero-Hinojosa Celso A. Espinoza Claudia Fabiola Méndez-Catalá Sungyun Kang Teruhiko Suzuki Natsuki Kosaka-Suzuki Susan Robinson Vijayaraj Nagarajan Zhen Ye Abdelhalim Boukaba John E. J. Rasko Alexander V. Strunnikov Dmitri Loukinov Bing Ren Victor V. Lobanenkov 《Genome biology》2015,16(1)
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967.
Follicle‐stimulating hormone promotes age‐related endometrial atrophy through cross‐talk with transforming growth factor beta signal transduction pathway 下载免费PDF全文
Dan Zhang Jingyi Li Gufeng Xu Runjv Zhang Chengliang Zhou Yeqing Qian Yifeng Liu Luting Chen Bo Zhu Xiaoqun Ye Fan Qu Xinmei Liu Shuai Shi Weijun Yang Jianzhong Sheng Hefeng Huang 《Aging cell》2015,14(2):284-287
It is widely believed that endometrial atrophy in postmenopausal women is due to an age‐related reduction in estrogen level. But the role of high circulating follicle‐stimulating hormone (FSH) in postmenopausal syndrome is not clear. Here, we explored the role of high circulating FSH in physiological endometrial atrophy. We found that FSH exacerbated post‐OVX endometrial atrophy in mice, and this effect was ameliorated by lowering FSH with Gonadotrophin‐releasing hormone agonist (GnRHa). In vitro, FSH inhibited endometrial proliferation and promoted the apoptosis of primary cultured endometrial cells in a dose‐dependent manner. In addition, upregulation of caspase3, caspase8, caspase9, autophagy‐related proteins (ATG3, ATG5, ATG7, ATG12 and LC3) and downregulation of c‐Jun were also observed in endometrial adenocytes. Furthermore, smad2 and smad3 showed a time‐dependent activation in endometrial cells which can be partly inhibited by blocking the transforming growth factor beta receptor II (TβRII). In conclusion, FSH regulated endometrial atrophy by affecting the proliferation, autophagy and apoptosis of endometrial cells partly through activation of the transforming growth factor beta (TGFβ) pathway. 相似文献
968.
Xiangyang Wu Yong Wu Ruijuan Zheng Fen Tang Lianhua Qin Detian Lai Lu Zhang Lingming Chen Bo Yan Hua Yang Yang Wang Feifei Li Jinyu Zhang Fei Wang Lin Wang Yajuan Cao Mingtong Ma Zhonghua Liu Jianxia Chen Xiaochen Huang Jie Wang Ruiliang Jin Peng Wang Qin Sun Wei Sha Liangdong Lyu Pedro MouraAlves Anca Dorhoi Gang Pei Peng Zhang Jiayu Chen Shaorong Gao Felix Randow Gucheng Zeng Chang Chen XinShan Ye Stefan H E Kaufmann Haipeng Liu Baoxue Ge 《EMBO reports》2021,22(7)
Mycobacterial arabinogalactan (AG) is an essential cell wall component of mycobacteria and a frequent structural and bio‐synthetical target for anti‐tuberculosis (TB) drug development. Here, we report that mycobacterial AG is recognized by galectin‐9 and exacerbates mycobacterial infection. Administration of AG‐specific aptamers inhibits cellular infiltration caused by Mycobacterium tuberculosis (Mtb) or Mycobacterium bovis BCG, and moderately increases survival of Mtb‐infected mice or Mycobacterium marinum‐infected zebrafish. AG interacts with carbohydrate recognition domain (CRD) 2 of galectin‐9 with high affinity, and galectin‐9 associates with transforming growth factor β‐activated kinase 1 (TAK1) via CRD2 to trigger subsequent activation of extracellular signal‐regulated kinase (ERK) as well as induction of the expression of matrix metalloproteinases (MMPs). Moreover, deletion of galectin‐9 or inhibition of MMPs blocks AG‐induced pathological impairments in the lung, and the AG‐galectin‐9 axis aggravates the process of Mtb infection in mice. These results demonstrate that AG is an important virulence factor of mycobacteria and galectin‐9 is a novel receptor for Mtb and other mycobacteria, paving the way for the development of novel effective TB immune modulators. 相似文献
969.
970.
Water-soluble, biological-compatible, and excellent fluorescent CdSe/CdS quantum dots (QDs) with L-cysteine as capping agent were synthesized in aqueous medium. Fluorescence (FL) spectra, absorption spectra, and transmission electron microscopy (TEM) were employed to investigate the quality of the products. The interactions between QDs and bovine serum albumin (BSA) were studied by absorption and FL titration experiments. With addition of QDs, the FL intensity of BSA was significantly quenched which can be explained by static mechanism in nature. When BSA was added to the solution of QDs, FL intensity of QDs was faintly quenched. Fluorescent imaging suggests that QDs can be designed as a probe to label the Escherchia coli (E. coli) cells. These results indicate CdSe/CdS/L-cysteine QDs can be used as a probe for labeling biological molecule and bacteria cells. 相似文献