Immunochemical properties of the West Nile virus prM protein and the C-terminal fragment of the M protein

The cDNA fragments 466–966 and 878–1088 coding for the precursor M (prM) protein and polypeptide M_31–75-E_1–30 of the Russian strain LEIV-Vlg99-27889-human of the West Nile virus (WNV) were synthesized and cloned. The corresponding prM and M_31–75-E_1–30 recombinant polypeptides were purified by affinity chromatography. The prM polypeptide interacted with a polyclonal serum against WNV in ELISA and immunoblotting, demonstrating the immunochemical similarity of the recombinant polypeptide and the native WNV prM protein. Six species-specific monoclonal antibodies (mAbs) against the prM recombinant polypeptide recognized at least four epitopes on the recombinant polypeptides. In addition, mAb 7D11 displayed a virus-neutralizing activity. The patterns of mAb interactions with the prM, M_31–75-E_1–30, E_1–180, and E_260–466 recombinant polypeptides revealed cross-reacting epitopes in regions 260–466 of the E protein and 31–75 of the M_31–75-E_1–30 polypeptide and the WNV prM protein. A spatial model revealed structural similarity of the C-terminal regions of the E and M proteins of WNV, supporting the results of immunochemical experiments. Based on virus neutralization by mAb 7D11, which recognized an epitope mapping to region 31–75 of the WNV M protein, an important function in virus penetration into the cell was assumed for the C-terminal region of the M protein.     

基于模糊数学的秦岭地区山茱萸生境适宜性评价

山茱萸(Cornus officinalis)是我国传统常用药材,本文采用模糊数学分析方法,对采自秦岭地区的山茱萸中马钱苷含量与21个评价因子的隶属函数进行拟合,同时采用最大信息熵模型确定各个评价因子的权重,利用ArcGIS 10空间分析模块模拟研究区域适宜山茱萸生长的潜在分布生境。结果表明,在山茱萸生境的21个评价因子中,主要影响因子为气候,其次是土壤和地形因子;所有评价因子中,土壤质地(TTEX)的权重最大,其次是果实生长期降水量(PG)、年降水量(AP)和降水季节性变化(PS)。研究区内山茱萸高适宜区面积占总面积的19.94%,主要分布在甘肃东南部、陕西南部和河南西部,这些区域温度适中、气候湿润、光照充足,适宜山茱萸生长;适宜区面积占总面积的11.85%,低适宜区面积占总面积的16.31%,不适宜区面积占总面积的51.90%。本研究基于GIS与模糊数学的生境适宜性评价模型,对秦岭地区山茱萸生境适宜性做出了科学划分,同时量化了不同生境区的评价因子对山茱萸的影响,可为山茱萸的管理和保护以及人工种植提供科学依据。     

A biogeographical regionalization of Angolan mammals

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