硒化麒麟菜多糖对宫颈癌细胞株生长和淍亡的影响

目的：探讨硒化麒麟菜多糖在体外对宫颈癌Hela细胞株生长和凋亡的作用及机制。方法：以宫颈癌Hela细胞株为研究对象，用MTT法检测硒化麒麟菜多糖对肿瘤细胞增殖的影响，流式细胞仪检测细胞周期、细胞调亡以及凋亡基因Fas的表达情况，以顺铂为对照组，比较硒化麒麟菜多糖与顺铂的疗效。结果：硒化麒麟菜多糖可阻滞宫颈癌Hela细胞的生长使之停留在S和G2-M期，从而抑制了肿瘤细胞的增殖，同时通过促进Fas表达，诱导Hela细胞凋亡。结论：硒化麒麟菜多糖通过阻滞肿瘤细胞的生长及诱导细胞凋亡等机制，对宫颈癌细胞的增殖有一定的抑制作用。     

Gene flow from transgenic oilseed rape (Brassica napus L.) to cruciferous weeds under mentor pollen inducement

The alien gene flow between genetically modified glyphosate-resistant rapeseed variety Q3 (Brassica napus L.) and four cruciferous weeds was studied under mentor pollen inducement. The results showed that when Thlaspi arvense L., Capsella bursa-pastoris (L.) Medic, Cardamine hirsute L. and Rorippa palustris (L.) Besser were pollinated with mentor pollen, the mixed Q3 and the weed, pollen grains aggregated largely and germinated quickly, and the numbers of pollen tubes penetrating into the style and the ovary were greatly increased as compared with corresponding self-pollination groups. Twenty four to forty eight hours after pollination, several pollen tubes were observed to penetrate into the ovule via micropyle in each mentor combination. However, when the mentor progenies were analyzed by PCR, all of them showed negative for the Q3 herbicide-resistant gene. Collectively, these results indicated that crossing between T. arvense, C. bursa-pastoris, C. hirsuta, R. palustris (as female) and Q3 (as male) was highly incompatible and the herbicide-resistant gene could not flow from Q3 to these four weeds.     

假单孢菌PKE117木素过氧化物酶的酶学性质及基因克隆

对纯化得到的假单孢菌PKE117的胞外木素过氧化物酶的酶学性质进行了初步研究,发现其最适pH为5.0,最适温度为30℃,以藜芦醇为底物,在25℃,pH3.0的琥珀酸钠缓冲液中与底物反应时的Km值为(0.277±0.0008)mmol/L,vmax为(0.049±0.001)mmol.mg-1protein.min-1。根据LiP已知保守序列设计引物,提取质粒,扩增得到一条199bp的DNA片段lip1和一条563bp的DNA片段lip2,序列比对结果显示与已报道的白腐真菌过氧化物酶基因的同源性不是很高。核苷酸翻译后的氨基酸序列比对结果发现,LiP1与Pycnoporus sanguineus的漆酶的同源性达到100%,与Mycobacteriumbovis的木素过氧化物酶的同源性达到80%;LiP2与Arabidopsis thaliana的过氧化物酶同源性达到100%,与Hordeum vulgare的过氧化物酶1同源性为75%。     

Synthesis dynamic and developmental profile of prothoracicotropic hormone between diapause- and nondiapause-destined individuals in Helicoverpa arrnigera

Biosynthesis and secretion of prothoracicotropic hormone （PTTH） of diapause- and nondiapausedestined individuals in Helicoverpa armigera were studied using whole-mount immunocytochemistry and enzyme-linked immunosorbent assay （ELISA）. The immunocytochemistry revealed that PTTH is expressed in two pairs of lateral neurosecretory cells of the brain. The presence of immunoreactivity has not significant difference between the brains of the diapause- and nondiapause-destined 6th instar larvae. However, the obvious differences of expressional pattern from day 4 pupae were observed between the two types. PTTH titers in hemolymph from the 6th instar larvae to pharate adults were measured by the ELISA. Although there were similar titer changes between the two types of individuals at the larval stage, a significant difference from developmental expression was detected at the pupal stage, suggesting that the expression and secretion of PTTH does play a crucial role in regulation of pupal diapause of H. armigera.     

Cloning and characterization of a new actin gene from Oryza sativa L.

Using Rho family member osRACD as bait, a new member of actin gene family -Act was isolated from Oryza sativa by yeast two-hybrid system. The full-length cDNA was cloned with 5' RACE technology, which contains an open reading frame of 1134 bp with a predicted protein of 377 amino acids. Sequence alignment revealed 96% to 81.8% identities with some known actin proteins in plants. The method of bioinformatics was used to analyze the protein modification sites, structure and evolution of the gene. Southern blot analysis showed that Act is a single-copy gene in the genome. The result of RT-PCR showed it is ubiquitously expressed in root, shoot, callus and panicle in a temporal fashion. The relationship between Rho family and actin family in evolution and function was also studied.     

不同区域日本稻蝗Cyt b基因序列及相互关系

对中国 7个不同地理区域的日本稻蝗共 19个个体的线粒体 DNA细胞色素 b基因中间部分序列进行测定 ,比较其同源性 ,计算碱基组成 ,并用中华稻蝗和景泰突颜蝗为外群构建不同单倍型的 NJ分子系统树。在获得的432 bp的序列中 ,A T约占 70 .5 % ,其中 13个核苷酸位点存在变异 (约占 3.0 % ) ,4个位点引起了氨基酸的变异。就每个氨基酸密码子来看 ,第三位点的 A T含量较高 ,达 87.4%。由系统树显示 ,6个单倍型共形成 3个聚类簇 ,其分枝与地理分布没有直接的关系     

用荧光双链引物特异扩增并定量核酸

描述了一种利用特殊的双链引物－－突触引物，用于核酸扩增的特异定量检测，在传统的引物的5'端标记荧光物质，而在引物的互补序列的3'端标记荧光淬灭剂以封闭其延伸。二者杂交即成双链突触引物。在制备PCR反应混合物阶段以及加热的初期，突触引物保持稳定的双链结构而不能引导扩增，在退火阶段，突触引物部分解链导致引物延伸，荧光物质与淬灭剂分开而产生荧光。利用人β珠蛋白基因对此方法进行了验证。这种可自行退火的荧光引物不仅简单地实现了实时扩增，同时比常规的热启动PCR更有效地提高了扩增的特异性。