马铃薯StPSKRs基因的克隆及其亚细胞定位分析

该研究采用同源克隆与PCR扩增方法,从马铃薯品种‘Desiree’中克隆植物磺肽素受体基因StPSKR1和StPSKR2的全长cDNA,并对其进行生物信息学分析及亚细胞定位分析,为深入研究StPSKR1和StPSKR2基因在马铃薯生长发育和生物胁迫中的作用提供理论依据。结果发现:(1)通过同源克隆与PCR扩增获得StPSKR1和StPSKR2的全长cDNA片段,并将其克隆到pGWB5-GFP载体;测序结果显示这2个基因编码的蛋白质与数据库给定的蛋白质序列保持一致,表明成功克隆到StPSKR1和StPSKR2基因。(2)StPSKR1位于马铃薯1号染色体上,cDNA全长3 042 bp,编码1 013个氨基酸,预测蛋白相对分子质量为112.16 kD,理论等电点6.27;StPSKR2位于7号染色体,cDNA全长3 135 bp,编码1 044个氨基酸,相对分子量为114.99 kD,理论等电点6.19。(3)生物信息学分析显示,StPSKR1和StPSKR2都属于跨膜蛋白。(4)亚细胞定位结果显示,StPSKR1和StPSKR2均定位于细胞膜上。     

Phylogenetic analysis of Nosema antheraeae (Microsporidia) isolated from Chinese oak silkworm, Antheraea pernyi

The microsporidian Nosema antheraeae is a pathogen that infects the Chinese oak silkworm, Antheraea pernyi. We sequenced the complete small subunit (SSU) rRNA gene and the internal transcribed spacer (ITS) of N. antheraeae, and compared the SSU rRNA sequences in other microsporidia. The results indicated that Nosema species, including N. antheraeae, formed two distinct clades, consistent with previous observations. Furthermore, N. antheraeae is clustered with N. bombycis with high bootstrap support. The organization of the rRNA gene of N. antheraeae is LSU-ITS1-SSU-ITS2-5S, also following a pattern similar to the Nosema type species, N. bombycis. Thus, N. antheraeae is a Nosema species and has a close relationship to N. bombycis.     

大连长山群岛海岸带沉积物微生物群落结构特征

【目的】为揭示海岸带微生物群落结构在人类活动影响下的分布差异及对环境因子变化的响应趋势,【方法】本实验采用t-RFLP和DGGE技术,对大连长山群岛不同功能类型海岸潮间带沉积物中的微生物群落结构特征进行比对和分析,并通过16S rRNA基因文库解析养殖污染站位的微生物群落结构特征。【结果】T-RFLP的t-RF分析显示,养殖污染严重站位的微生物丰度、香农指数和均匀度明显高于其它站位。通过对t-RFLP色谱峰和DGGE图谱聚类分析发现,处于旅游区的2个站位微生物群落结构相似度较高,养殖区随污染程度加重与旅游区的群落结构差异增大。对污染严重站位建立的克隆文库显示变形菌门(Proteobacteria)为优势菌群,其中γ-变形菌门是主要存在的亚门微生物。【结论】T-RFLP和DGGE技术从不同方面反映了环境中的微生物群落结构特征,研究结果表明养殖污染区的微生物群落结构发生明显变化,其影响大于地理隔离效应,污染严重区域的微生物群落中存在大量肠杆菌属,且多个物种与富营养化和赤潮相关联,如拟杆菌门和α-变形细菌红细菌目的细菌。     

非磷酸化肌球蛋白在血小板衍生生长因子诱导的血管平滑肌细胞迁移中的作用

为了阐明非磷酸化肌球蛋白在平滑肌细胞迁移中的作用,研究探讨了非磷酸化肌球蛋白是否介导了血小板衍生生长因子(PDGF)诱导豚鼠脑基底动脉平滑肌细胞(GbaSM-4)的迁移。研究结果显示,20ng/ml以下剂量的PDGF可诱导GbaSM-4细胞发生迁移,此时肌球蛋白轻链(MLC20)磷酸化水平无变化。该迁移作用可被肌球蛋白特异性抑制剂blebbistatin所拮抗。应用RNA干扰技术抑制肌球蛋白轻链激酶表达,经免疫印迹检测经果显示,MLC20的磷酸化水平发生了显著下降;但对PDGF诱导的迁移作用无影响;在RNA干扰后blebbistatin也可抑制其迁移作用。体外ATP酶活性测定结果显示,blebbistatin对从平滑肌中提取的非磷酸化肌球蛋白的ATP酶活性有明显的抑制作用,其主要作用位点位于肌球蛋白头的头部S1。上述结果提示,非磷酸化的肌球蛋白参与了PDGF诱导的平滑肌细胞迁移。     

Secretory delivery of heterologous proteins in attenuated <Emphasis Type="Italic">Vibrio anguillarum</Emphasis> for potential use in vaccine design

To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development.     

《环境工程微生物学》设计性实验的开设

设计性实验项目的开设是培养学生创新能力的有效途径。阐述了在环境工程微生物学实验中增加设计性实验的必要性,并从设计项目的布置,设计方案的撰写,可行性论证及竞标、中标方案的实施、答辩与考核等方面介绍项目的实施过程。     

Extrinsic and intrinsic factors influencing the emergence and return of the Asian particolored bat Vespertilio sinensis to the summer roost

Circadian rhythms play a crucial role in the health and survival of organisms. However, little is known concerning how intrinsic and extrinsic factors affect animal daily rhythms in the field, especially in nocturnal animals. Here, we investigated the first emergence, mid‐emergence, and return times of Vespertilio sinensis, and also integrated environmental conditions (temperature, humidity, and light intensity) and biotic factors (reproductive status and predation risk) to determine causes of variation in the activity rhythms of the bats. We found that variation in the first emergence time, the mid‐emergence time, and the final return time were distinct. The results demonstrated that the emergence and return times of bats were affected by light intensity, reproductive status, and predation risk in a relatively complex pattern. Light intensity had the greatest contribution to activity rhythms. Moreover, we first investigated the effects of actual predators on the activity rhythms of bats; the results showed that the mid‐emergence time of bats was earlier as predators were hunting, but the final return time was later when predators were present. Finally, our results also highlighted the importance of higher energy demands during the lactation in bats to variation in activity rhythms. These results improve our understanding of the patterns and causes of variation in activity rhythms in bats and other nocturnal animals.