雪莲果离体培养及植株再生体系的建立

对雪莲果幼嫩叶片和腋芽离体培养与植株再生过程进行了研究,建立了雪莲果的再生体系.该体系以雪莲果叶片和腋芽为材料进行离体培养,结果表明:MS可作为雪莲果再生体系的基本培养基;叶片、腋芽诱导愈伤组织和不定芽培养基为MS 6-BA 2/0 mg/L NAA 0.2mg/L 蔗糖3%;继代培养基为MS 6-BA 1.0 mg/L NAA 0.1 mg/L 蔗糖3%;生根培养基为1/2 MS IAA 0.3 mg/L 蔗糖3%.     

魔芋"多叶"现象的研究进展

主要从激素诱导、辐射诱变及实生种子在生长过程出现的"多叶"现象的研究现状进行了综述,并对魔芋"多叶"现象今后的研究方向作出了展望.     

瓜类蔬菜组织培养与遗传转化研究进展

概述了瓜类蔬菜组织培养过程中的主要影响因素—基因型、外植体类型,部位与生理状态、培养基、生长调节物质、碳源及其他添加物质对植株再生的影响,以及根癌农杆菌介导的瓜类蔬菜遗传转化的影响因素与研究进展。     

Juglone inhibits epithelial-mesenchymal transition of prostate cancer cells by regulating Wnt/β-catenin/Snail signaling pathway

AIM: To investigate the mechanism of juglone on epithelial-mesenchymal transition in prostate cancer cells. METHODS: Human prostate cancer LNCaP cells were divided into control group (without juglone), 12.5 μmol/L juglone group and 25 μmol/L juglone group. LNCaP cells in the latter 2 groups were treated with juglone for 24 h. The invasion ability of the LNCaP cells was detected by Transwell assay. The protein expression of E-cadherin, vimentin, Snail and β-catenin was determined by Western blot. The LNCaP cells were treated with LiCl and juglone in combination for 24 h, and the protein expression of Snail and E-cadherin was detected by Western blot.RESULTS: The results of Trans-well invasion assay showed that the invasion ability in juglone groups was significantly decreased (P<0.01). The protein expression of E-cadherin in the LNCaP cells treated with juglone was increased, and the expression levels of vimentin and β-catenin were reduced (P<0.01). Treatment with LiCl significantly attenuated the inhibitory effect of juglone on Snail expression and subsequent down-regulation of E-cadherin expression. CONCLUSION: Juglone inhibits the epithelial-mesenchymal transition by inhibiting the Wnt/β-catenin/Snail signaling pathway in the LNCaP cells.     

Effects of Ku70 on protein expression of HTLV-1 in HTLV-1 positive T cells

AIM:To explore the effects of Ku70 on the protein expression of human T-lymphotrophic virus 1 (HTLV-1) in HTLV-1 positive T cells. METHODS:The expression level of Ku70 in HTLV-1 positive T cells was exa-mined by Western blot. The siRNA targeting Ku70 was constructed and the effect of the siRNA on knockdown of Ku70 expression was determined by Western blot. After knockdown of Ku70 expression in the HTLV-1 positive T cells by siRNA, the expression of HTLV-1-related proteins at mRNA and protein levels was examined by real-time PCR and Western blot, and the expression levels of interferons and proinflammatory cytokines were examined by real-time PCR. RESULTS:The HTLV-1 positive T cells, including MT2, MT4 and C8199 cells, displayed a higher expression level of Ku70. The protein expression of HTLV-1 was increased in Ku70-silencing MT2 cells and MT4 cells. After knockdown of Ku70 expression in the MT2 cells and MT4 cells, the production of interferon (IFN)-α, IFN-γ and tumor necrosis factor-α was reduced.CONCLUSION:The HTLV-1 positive T cells have a higher expression level of Ku70. In HTLV-1 positive T cells, Ku70 promotes the production of interferons and proinflammatory cytokines and inhibits HTLV-1-related protein expression.     

‘槟榔芋’和‘香沙芋’母芋与子芋淀粉形态和理化性质的比较

以魁芋类的‘槟榔芋’和多子芋类的‘香沙芋’为材料,运用扫描电镜、X–射线衍射和快速黏度分析等技术比较研究了两个芋品种的母芋和子芋中淀粉的理化性质的差异。结果表明:‘槟榔芋’母芋淀粉的平均粒径大于子芋,‘香沙芋’相反。两种芋的母芋表观直链淀粉含量和淀粉颗粒外部有序度均高于其子芋。在加热过程中,两种芋的母芋和子芋淀粉的膨胀势在75℃后产生显著变化,在95℃时母芋淀粉的膨胀势大于子芋。和子芋淀粉相比,‘槟榔芋’母芋淀粉具有较高的峰值黏度、崩解值和回生值,而‘香沙芋’相反。两种芋的母芋淀粉的最终水解程度均大于其子芋。以上结果表明,两个芋品种的母芋和子芋淀粉的形态、组成和理化性质方面均存在明显差异,这将为芋淀粉在食品和非食品行业中的应用提供参考依据。     

猪食欲肽2受体突变体真核表达载体的构建及其对cAMP信号通路的影响

试验旨在构建猪食欲肽2受体（porcine orexin 2 receptor,pOX2R）突变体的真核表达载体,探究其野生型与突变体的基础药理学活性差异。以pcDNA3.1（+）-myc/pOX2R野生型质粒为模板,设计特异性引物单点突变构建4种突变体：pcDNA3.1（+）-myc/pOX2R-P10S、pcDNA3.1（+）-myc/pOX2R-P11T、pcDNA3.1（+）-myc/pOX2R-V308I和pcDNA3.1（+）-myc/pOX2R-T401I,将pcDNA3.1（+）-myc/pOX2R野生型和4种突变体分别瞬时转染HEK293T细胞,利用双荧光素酶报告基因检测法测定pOX2R野生型及突变体的基础活性,并检测不同浓度激动剂作用下细胞内cAMP水平,随后用内源性激动剂食欲肽A （OXA）及食欲肽B （OXB）分别对野生型及突变体进行刺激。结果显示,4个突变体构建成功,pOX2R的第10、11、308和401位氨基酸分别突变为丝氨酸、苏氨酸、异亮氨酸和缬氨酸。将pOX2R的野生型及4个突变体瞬时转染HEK293T细胞后,野生型与突变体的基础活性值无显著差异（P>0.05）,表明这4个位点的氨基酸突变对其受体的基础表达信号无显著影响。与野生型受体相比,突变型受体对激动剂OXB的响应无显著差异（P>0.05）,而突变体P10S、P11T和T401I对激动剂OXA的响应EC₅₀显著降低（P<0.05）,其R_max无显著差异（P>0.05）。推测第10、11和401位点的氨基酸突变可能影响了激动剂OXA与受体的结合,降低了激动剂的激动效应。本研究结果为进一步体外研究pOX2R的功能奠定了基础。     

猫泛白细胞减少症病毒北京株NS1基因克隆与生物信息学分析

为分析猫泛白细胞减少症病毒（FPV）北京株（FPV-BJ 05株）NS1基因的分子特征及其编码蛋白的生物学功能,本研究对FPV-BJ 05株NS1基因进行PCR扩增、克隆及序列测定。应用生物信息学软件分析FPV-BJ 05株与GenBank上登录的11株FPV参考株NS1基因的同源性,并预测NS1蛋白理化性质、信号肽、跨膜结构、B细胞抗原表位、磷酸化位点、亚细胞定位及蛋白结构与功能、高级结构等。结果显示,NS1基因全长2 007 bp,编码668个氨基酸,且与其他FPV分离株NS1基因核苷酸序列同源性为98.8%~99.3%,氨基酸序列同源性为97.9%~98.8%。系统进化树分析结果显示,FPV-BJ 05株NS1蛋白与GenBank上登录的3株FPV参考株处于同一大分支,但由于氨基酸的突变导致其属于独立的一小分支。NS1蛋白既无信号肽也无跨膜结构域,属于非分泌型的疏水性蛋白。B细胞抗原表位预测结果显示,NS1蛋白柔韧性较好,抗原性及表面可及性较高,预测该蛋白含有13个优势抗原位点。修饰结构预测表明,NS1蛋白含有62个潜在磷酸化位点,27个O-糖基化位点和2个N-糖基化位点。亚细胞定位结果显示,NS1蛋白在细胞质和细胞核的概率较高,分别为69.6%和17.4%。NS1蛋白二级结构中α-螺旋、延伸链、无规则卷曲和β-转角分别占39.37%、15.42%、39.37%和5.84%。应用在线软件SWISS-Modle对NS1蛋白进行建模,预测其三级结构,结果发现NS1蛋白主要以α-螺旋为主。本试验结果将为北京地区FPV免疫诊断及核酸疫苗研究提供理论依据。     

国内主要十字花科抗根肿病品种在湖北病区的表现

在湖北省宜昌市长阳县和利川市对25个抗根肿病的十字花科蔬菜品种进行了集中试验示范,其中大白菜品种19个、甘蓝品种3个、萝卜品种3个。结果表明:长阳根肿病菌的致病力较利川根肿病菌强,绝大多数参试大白菜品种不抗长阳根肿病菌但抗利川根肿病菌,仅京春CR2和京春CR3兼抗长阳根肿病菌和利川根肿病菌,综合经济性状表现优秀,京春CR2和京春CR3可以在长阳、利川及类似根肿病菌生理小种区域推广,其他单抗利川根肿病菌的大白菜品种可在利川及类似根肿病菌生理小种区域推广;萝卜品种雪单3号在长阳表现为耐病,在利川表现为抗病,综合经济性状良好;甘蓝品种2012070甘蓝在长阳表现为耐病,参试甘蓝品种均不抗利川根肿病菌。     

大气氮沉降及其对草地生物多样性的影响

随着人类活动的加强,大气氮素沉降在逐渐增加, 已对海洋和陆地生态系统产生了明显的影响.为此总结了大气干湿沉降中氮的组成和数量变化等特点,并在此基础上,分析评述了大气氮沉降对草地生态系统中植物、动物和微生物群落发展的影响,提出了今后研究的方向.