高原鼠兔瘦素蛋白乳腺特异表达载体的构建及细胞表达

瘦素(Leptin)蛋白是调节机体能量代谢的关键因子之一。前期研究显示高原鼠兔Leptin蛋白发生了适应性进化。功能实验表明,在温暖或寒冷条件下高原鼠兔Leptin通过减少食物摄取和增加能量消耗调节能量平衡,显示了其调节适应性产热过程的潜力。本研究以高原鼠兔Leptin cDNA为模板扩增高原鼠兔obese (ob)基因编码区序列504 bp,改造并构建哺乳动物真核细胞乳腺特异表达载体pBC1-lep,同时通过组织块法原代培养建立奶山羊乳腺上皮细胞系,并通过pBC1-lep质粒脂质体法转染及转基因细胞的筛选,成功获得转染Leptin的阳性细胞。本研究为利用转基因动物实现奶山羊乳腺中特异表达高原鼠兔Leptin提供了一条可能的途径,完成了乳腺特异真核表达载体的构建。     

樟子松针叶化学成分研究

该研究以采自黑龙江省齐齐哈尔市的樟子松(Pinus sylvestris)针叶为对象,采用溶剂提取法对樟子松针叶中的化学成分进行提取,应用硅胶柱色谱、制备薄层色谱和高效液相色谱等现代色谱技术对提取浸膏中的化学成分进行分离和纯化,运用质谱,核磁(1H-NMR和13C-NMR)等波谱技术,鉴定了化合物结构,并对提取浸膏的抑菌活性进行了测试。结果表明:从樟子松针叶提取物中分离得到15个化合物,分别鉴定为松叶酸(1)、松叶酸甲酯(2)、18α-acetoxylabd-8(17)-en-15-oic acid (3)、4-eplimbricataloic acid (4)、15-乙基-18-松叶酸甲酯(5)、15-acetoxy-labda-8(17),13E-dien-18-al (6)、7β-羟基脱氢枞酸(7)、7α-羟基脱氢枞酸(8)、endo-peroxide (9)、α-杜松醇(10)、β-谷甾醇(11)、邻苯二甲酸二丁酯(12)、7R,11R-phytol (13)、正二十四烷醇(14)、N-octacosan7β-ol (15)。其中,化合物9,13,14和15为首次从该属植物中分离得到。抑菌活性结果表明,正己烷萃取浸膏在浓度为5~100 mg·mL~(-1)时对大肠杆菌和枯草芽孢菌的抑菌率分别为53%~71%和56%~70%,在浓度为50 mg·mL~(-1)和100 mg·mL~(-1)时对金黄色葡萄球菌的抑菌率分别为51%和69%。该研究课题进一步明确了樟子松针叶中的化学成分,为其活性测试及应用研究提供依据。     

5-HT和DA对虾蟹打斗行为影响的研究进展

5-羟色胺(5-HT)和多巴胺(DA)是两种神经递质,可与众多不同类型的受体结合发挥多种重要的生理功能.现已证明其广泛分布于多种动物的不同组织中,在动物的打斗行为活动中起着重要的调节作用.目前,在虾蟹中已被报道的5-HT受体主要有5种,分别是5-HT1A、5-HT1B、5HT2A、5HT2B和5-HT7;DA受体主要为DA1A、DA1B、DA2和DA4.5-HT和DA及其受体分布存在明显的种属和组织特异性.5-HT和DA参于了虾蟹打斗行为的调节过程并有不同的调节机理.5-HT可以调节环磷酸腺苷(cAMP)或高血糖激素(CHH)的释放,促进或抑制虾蟹打斗行为;而DA同样能够通过调节cAMP及COMT等物质的释放来调节虾蟹打斗行为.     

Development of high‐resolution DNA barcodes for Dioscorea species discrimination and phylogenetic analysis

The genus Dioscorea is widely distributed in tropical and subtropical regions, and is economically important in terms of food supply and pharmaceutical applications. However, DNA barcodes are relatively unsuccessful in discriminating between Dioscorea species, with the highest discrimination rate (23.26%) derived from matK sequences. In this study, we compared genic and intergenic regions of three Dioscorea chloroplast genomes and found that the density of SNPs and indels in intergenic sites was about twice and seven times higher than that of SNPs and indels in the genic regions, respectively. A total of 52 primer pairs covering highly variable regions were designed and seven pairs of primers had 80%–100% PCR success rate. PCR amplicons of 73 Dioscorea individuals and assembled sequences of 47 Dioscorea SRAs were used for estimating intraspecific and interspecific divergence for the seven loci: The rpoB‐trnC locus had the highest interspecific divergence. Automatic barcoding gap discovery (ABGD), Poisson tree processes (PTP), and generalized mixed Yule coalescence (GMYC) analysis were applied for species delimitation based on the seven loci and successfully identified the majority of species, except for species in the Enantiophyllum section. Phylogenetic analysis of 51 Dioscorea individuals (28 species) showed that most individuals belonging to the same species tended to cluster in the same group. Our results suggest that the variable loci derived from comparative analysis of plastid genome sequences could be good DNA barcode candidates for taxonomic analysis and species delimitation.     

温度对取食玉米籽粒桃蛀螟生长发育、存活和生殖的影响

为了明确不同温度对取食玉米籽粒桃蛀螟生长发育、存活和生殖的影响,本研究依据年龄-龄期两性生命表理论计算了在21、24、27和30 ℃下取食玉米籽粒的桃蛀螟种群的生命表参数,并基于这些参数预测了未来80 d的种群动态。结果表明: 在21、24、27和30 ℃下桃蛀螟均能完成1个世代,随着温度升高,各阶段的发育历期缩短,且温度间差异显著。24 ℃下的平均单雌产卵量最高(116.7粒),成虫前期存活率最高(84.7%),雌虫占比最高(0.46),均显著高于其他温度。24、27、30 ℃下种群的内禀增长率分别为0.1059、0.1101、0.1045 d^-1,周限增长率分别为1.1117、1.1164、1.1102 d^-1,处理间差异不显著,但均显著高于21 ℃处理。21、24、27和30 ℃下的净增殖率(R₀)分别为17.3、53.7、36.9、19.8个后代个体,其中24 ℃时的R₀最高且显著高于其他温度处理。表明桃蛀螟种群在24～27 ℃下的存活率高、繁殖力大、雌性占比较高,是其生长发育、生存和繁殖的适合温度。     

N+离子注入诱变选育高效降酚菌的研究

以合肥钢铁厂焦化废水处理厂的活性污泥为对象,从中驯化筛选得到降酚菌株并利用离子束对出发菌株进行诱变筛选,获得高效降解菌株KE2,它与出发菌株KE相比较,降解苯酚的能力显著提高。在温度为30℃左右,pH值为7时,KE2菌株生长和降解苯酚情况最佳,适量的外加碳源(葡萄糖)对KE2的生长和降酚率有促进作用。     

新一代生物防治及其在天敌瓢虫中的研究进展

生物防治是一种利用自然天敌控制有害生物的手段.当前生物防治的发展面临着使用成本高和效果不稳定的两大难题.这要求我们更精准地选育和释放天敌.随着测序技术的进步,学界提出了新一代生物防治(Next Generation Biological Control),旨在利用遗传学和基因组学来认识天敌昆虫种下水平的多样性和变异规律...     

Extracellular ATP inhibits root gravitropism at concentrations that inhibit polar auxin transport

Raising the level of extracellular ATP to mM concentrations similar to those found inside cells can block gravitropism of Arabidopsis roots. When plants are grown in Murashige and Skoog medium supplied with 1 mM ATP, their roots grow horizontally instead of growing straight down. Medium with 2 mM ATP induces root curling, and 3 mM ATP stimulates lateral root growth. When plants are transferred to medium containing exogenous ATP, the gravity response is reduced or in some cases completely blocked by ATP. Equivalent concentrations of ADP or inorganic phosphate have slight but usually statistically insignificant effects, suggesting the specificity of ATP in these responses. The ATP effects may be attributable to the disturbance of auxin distribution in roots by exogenously applied ATP, because extracellular ATP can alter the pattern of auxin-induced gene expression in DR5-beta-glucuronidase transgenic plants and increase the response sensitivity of plant roots to exogenously added auxin. The presence of extracellular ATP also decreases basipetal auxin transport in a dose-dependent fashion in both maize (Zea mays) and Arabidopsis roots and increases the retention of [(3)H]indole-3-acetic acid in root tips of maize. Taken together, these results suggest that the inhibitory effects of extracellular ATP on auxin distribution may happen at the level of auxin export. The potential role of the trans-plasma membrane ATP gradient in auxin export and plant root gravitropism is discussed.