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1.
Spines or trichomes on the fruit of cucumbers enhance their commercial value in China. In addition, glabrous mutants exhibit resistance to aphids and therefore their use by growers can reduce pesticide residues. Previous studies have reported two glabrous mutant plants containing the genes, csgl1 and csgl2. In the present study, a new glabrous mutant, NCG157, was identified showing a gene interaction effect with csgl1 and csgl2. This mutant showed the glabrous character on stems, leaves, tendrils, receptacles and ovaries, and there were no spines or tumors on the fruit surface. Inheritance analysis showed that a single recessive gene, named csgl3, determined the glabrous trait. An F2 population derived from the cross of two inbred lines 9930 (a fresh market type from Northern China that exhibits trichomes) and NCG157 (an American processing type with glabrous surfaces) was used for genetic mapping of the csgl3 gene. By combining bulked segregant analysis (BAS) with molecular markers, 18 markers, including two simple sequence repeats (SSR), nine insertion deletions (InDel) and seven derived cleaved amplified polymorphism sequences (dCAPs), were identified to link to the csgl3 gene. All of the linked markers were used as anchor loci to locate the csgl3 gene on cucumber chromosome 6. The csgl3 gene was mapped between the dCAPs markers dCAPs-21 and dCAPs-19, at genetic distances of 0.05 cM and 0.15 cM, respectively. The physical distance of this region was 19.6 kb. Three markers, InDel-19, dCAPs-2 and dCAPs-11, co-segregated with csgl3. There were two candidate genes in the region, Csa6M514860 and Csa6M514870. Quantitative real-time PCR showed that the expression of Csa6M514870 was higher in the tissues of 9930 than that of NCG157, and this was consistent with their phenotypic characters. Csa6M514870 is therefore postulated to be the candidate gene for the development of trichomes in cucumber. This study will facilitate marker-assisted selection (MAS) of the smooth plant trait in cucumber breeding and provide for future cloning of csgl3.  相似文献   
2.
通过DNA体外重组技术,以pET-3b为表达载体,构建了重组表达质粒pET-6R(B)和PET-6R(B)4,分别编码28kD的hIL-6R配基结合区片段及其53kD的二联体蛋白,并为酶切分析和DNA序列分析所证实。SDS-PAGE分析表明,含有重组表达质粒的菌株可分别表达出28kD的蛋白rIL6R-28和53kD的rIL6R-53。重组蛋白分别占菌体总蛋白的45%和29%左右。重组蛋白主要以包涵体形式存在,Western印迹表明重组蛋白具有IL-6R的抗原性。  相似文献   
3.
本新种与皱皮杜鹃(Rhododendron wiltonii Hemsl.et Wils.)相近似,区别在于前者叶较小,长6.8~8.0 cm,宽2.0~2.5 cm,叶表面平坦而不呈泡状突起,叶背密被一层黄色至锈红色毡毛,花5~6(~9)朵,较小,长约2.5 cm,易于区别。  相似文献   
4.
5.
血管紧张素Ⅱ在小鼠卵泡闭锁中的作用   总被引:1,自引:0,他引:1  
Cheng Y  Jiao LH  Liu RH  Wang QB  Wang H  Xia GL 《生理学报》2002,54(1):75-78
应用幼年小鼠经孕马血清促性腺激素(pregnant mares serum gonadotropin,PMSG)处理的动物模型,研究了卵泡从发育到闭锁动态变化过程中血管紧张素Ⅱ(AngⅡ)的作用。结果表明:(1)24日龄小鼠给予PMSG(10IU/只)后6d时,卵巢中出现大量闭锁卵泡,颗粒细胞DNA琼脂糖电泳显示了梯形条带;(2)随卵泡闭锁发生,卵巢AngⅡ含量增加;(3)AngⅡ显著拮抗FSH刺激颗粒细胞雌二醇生成的作用。我们认为,AngⅡ参与了对小鼠卵泡闭锁的调节。  相似文献   
6.
Copper (Cu(II)) and nickel (Ni(II)) are often encountered in wastewaters. This study investigated the individual toxic effects of long-term addition of Cu(II) and Ni(II) on the biochemical properties of aerobic granules in sequencing batch reactors (SBRs). The biochemical properties of aerobic granules were characterized by extracellular polymeric substances (EPS) content, dehydrogenase activity, microbial community biodiversity, and SBR performance. One SBR was used as a control system, while another two received respective concentration of Cu(II) and Ni(II) equal to 5 mg/L initially and increased to 15 mg/L on day 27. Results showed that the addition of Cu(II) drastically reduced the biomass concentration, bioactivity, and biodiversity of aerobic granules, and certainly deteriorated the treatment performance. The toxic effect of Ni(II) on the biodiversity of aerobic granules was milder and the aerobic granular system elevated the level of Ni(II) toxicity tolerance. Even at a concentration of 15 mg/L, Ni(II) still stimulated the biomass yield and bioactivity of aerobic granules to some extent. The elevated tolerance seemed to be owed to the concentration gradient developed within granules, increased biomass concentration, and promoted EPS production in aerobic granular systems.  相似文献   
7.
Effects of caffeine on in vivo and in vitro oocyte maturation in mice   总被引:2,自引:0,他引:2  
The objective was to investigate, using a mouse model, the effects of caffeine on the number of ovulated oocytes, the rate of oocyte maturation, the susceptibility of oocytes to activating stimuli, spindle morphology, and distribution of cortical granules (CGs). Mice were given caffeine (150 mg/kg body weight ip) at various times relative to hCG (-2, 0, and +2h); in an in vitro study, 1, 5 or 10 mM caffeine was added to the maturation culture. Caffeine had no effect on the quality of oocytes in vivo maturation, but caffeine was detrimental to the quality of oocytes matured in vitro. Further studies are needed to determine caffeine concentration in follicles relative to that in culture medium.  相似文献   
8.
体内能量代谢是维持机体正常生理活动的基础,而脂肪细胞的脂解是能量代谢的核心反应之一,调控脂肪酸从TG库释放,后由血清白蛋白转运至体内各个组织以满足能量需要。如果脂解作用出现障碍,就会影响机体能量的平衡进而引发肥胖和胰岛素抵抗等疾病。表没食子儿茶素没食子酸酯(Epig  相似文献   
9.
Histone modifications are thought to play important roles in various cellular functions. In this article, the distribution patterns of acetylation on histone H4, methylation on histone H3 lysine 9, and phosphorylation on histone H3 serine 10 were examined in in vivo and in vitro fertilization (IVF) preimplantation mouse embryos by using indirect immunofluorescence and scanning confocal microscopy. We desired to know whether the IVF, which has been widely used as a routine assisted reproductive technology in animal and human, was safe at the epigenetic level. As results, we found that there was no difference in these histone modification patterns in in vivo and IVF mouse embryos from zygote to blastocyst stage. Moreover, these histone modifications had different distributions at all examined stages, but they were consistent with the mouse embryo developmental stages.  相似文献   
10.
干细胞移植治疗肿瘤具有重要的临床价值.应用人间充质干细胞条件培养液作用H7402肝癌细胞,拟探讨间充质干细胞对肿瘤细胞的抑制作用,为今后应用人间充质干细胞进行肿瘤细胞治疗奠定理论基础.应用胎儿真皮来源的 Z3 间充质干细胞和胎儿骨髓来源的 BMMS-03 间充质干细胞的条件培养液作用于H7402肝癌细胞,采用软琼脂克隆形成实验、流式细胞仪技术、基因芯片技术和免疫印迹技术观察 H7402 细胞的克隆形成、增殖和基因表达谱变化.结果显示,H7402 细胞在间充质干细胞条件培养液作用下,克隆形成和增殖受到了明显抑制;基因芯片检测结果显示,H7402 细胞在间充质干细胞条件培养液作用下有 23 个基因上调表达,17 个基因下调表达,这些差异表达的基因与细胞的转录调控、新陈代谢、信号转导、细胞周期、应激反应和细胞粘附等功能相关.本实验结果表明,人间充质干细胞对 H7402 肝癌细胞的克隆形成和增殖具有抑制作用,并有多种基因的表达发生改变,这些基因表达的改变可能参与了对上述肿瘤细胞的抑制.  相似文献   
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