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为研究肉瘤融合基因(fus)在鱼类中的功能, 在斑马鱼中利用CRISPR/Cas9基因突变技术使fus基因产生移码突变。fus-/-纯合突变体斑马鱼发育正常并且完全可育, 但体长和体重在幼鱼和成年阶段都小于野生型斑马鱼。此外, 相较于野生型斑马鱼, fus-/-纯合突变体斑马鱼不存在雌鱼身体比例大于雄鱼的性别异形现象。在fus-/-纯合突变体斑马鱼早期幼鱼发育阶段, 一些生长相关基因包括gh1、ghra、igf1、igf2a、stat5.1和socs6的表达水平显著低于野生型斑马鱼但其运动能力并未受到影响。因此, 不同于fus基因在哺乳动物中的功能, 它在斑马鱼中不参与运动神经元的发育, 但在调节鱼类躯体生长发育与两性生长异形方面有着重要的功能。 相似文献
53.
Jing YANG Jiang-Chong WU Zhi-Jian GU 《植物分类学报》2009,47(4):291-296
Abstract The karyomorphology of three species in Dipentodon (Dipentodontaceae), Perrottetia (Celastraceae), and Tapiscia (Tapisciaceae), namely Dipentodon sinicus, Perrottetia racemosa, and Tapiscia sinensis, was investigated in the present study. Recent molecular research has discovered close relationships among these three genera, which has led to the establishment of the order Huerteales with Perrottetia being placed in Dipentodontaceae. Herein we report the chromosome numbers of D. sinicus and P. racemosa for the first time, and present their karyotype formulas as 2n = 34 = 22 sm + 12 st (D. sinicus), 2n = 20 = 11 m + 9 sm (P. racemosa), and 2n = 30 = 22 m(2SAT) + 8sm (T. sinensis). Asymmetry of their karyotypes is categorized to be Type 3B in D. sinicus, Type 2A in P. racemosa, and Type 2A in T. sinensis. Each of the species shows special cytological features. Compared with Perrottetia, Dipentodon has a different basic chromosome number, a higher karyotype asymmetry, and different karyomorphology of its interphase nuclei, mitotic prophase, and metaphase. Thus, on the basis of these results, we have reservations regarding the suggestion of placing Dipentodon and Perrottetia together in the family Dipentodontaceae. 相似文献
54.
YANG Fuyu National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China 《中国科学:生命科学英文版》2006,49(6):513-518
Keshan disease (KD) is a potentially fatal form of cardiomyopathy (disease of the heart muscle) endemic in certain areas of China. From 1984 to 1986, a national comprehensive scientific investigation on KD in Chuxiong region of Yunnan Province in the southwest China was conducted. The investigation team was composed of epidemiologists, clinic doctors, pathologists, biochemists, biophysicists and specialists in ecological environment. Results of pathological, biochemical and biophysical as well as clinical studies showed: an obvious increase of enlarged and swollen mito- chondria with distended crista membranes in myocardium from patients with KD; significant reduc- tions in the activity of oxidative phosphorylation (succinate dehydrogenase, cytochrome oxidase, succinate oxidase, H -ATPase) of affected mitochondria; decrease in CoQ, cardiolipin, Se and GSHPx activity, while obvious increase in the Ca2 content. So, it was suggested that mitochondria are the predominant target of the pathogenic factors of KD. Before Chuxiong KD survey only a few cases of mitochondrial cardiomyopathy were studied. During the multidisciplinary scientific investiga- tion on KD in Chuxiong a large amount of samples from KD cases and the positive controls were examined. On the basis of the results obtained it was suggested that KD might be classified as a “Mitochondrial Cardiomyopathy” endemic in China. This is one of the achievements in the three years’ survey in Chuxiong and is valuable not only to the deeper understanding of pathogenic mechanism of KD but also to the study of mitochondrial cardiomyopathy in general. Keshan disease is not a genetic disease, but is closely related to the malnutrition (especially mi- croelement Se deficiency). KD occurs along a low Se belt, and Se supplementation has been effective in prevention of such disease. The incidence of KD has sharply decreased along with the steady raise of living standard and realization of preventive measures. At present, patients of KD are very sparse. In recent years the research on the non-KD mitochondrial cardiomyopathy has progressed rapidly. Given the advances in this aspect a minireview is written to evaluate the classification of KD as a kind of mitochondrial cardiomyopathy. 相似文献
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56.
植物体细胞无性系变异的分子基础 总被引:21,自引:0,他引:21
TheMoleculBasicofSomaclonalVariationinPlantsZhangChunyiYangHanmin(BiologyDepartmentofLanzhouUniversityLanzhou730000)近年来,随着植物细胞和组织培养技术的迅速发展与广泛应用,不断发现在培养细胞和再生植株中存在着各种不同的变异,其中有些是可以遗传的,这种可遗传的变异被称为体细胞无性系变异[39].变异的发生有其遗传学基础,具体表现在显微水平上的染色体数目和结构变异与分子水平上的基因突变、碱基修饰、基因扩增或丢失、基因重排以及转座因子的激活而影响核及细胞质基因的表达等等.目前,人们在已经积累的大量有… 相似文献
57.
58.
Chemical Constituents of the Roots of Vernonia cumingiana Benth. 总被引:1,自引:0,他引:1
Qing-Hua LIU Jing-Quan YUAN Mao-Rong SUO Jun-Shan YANG 《植物学报(英文版)》2005,47(8):1016-1020
To search for new and bioactive constituents from traditional Chinese medicines, a new steroidal saponin, named vernonioside G (1), was isolated from the roots of Vernonia cumingiana Benth. (Compositae). The structure of vernonioside G was elucidated using spectral methods, particularly two-dimensional nuclear magnetic resonance analysis. Together with the new compound, eight known compounds were also isolated and identified from the roots of V. cumingiana, among which, VE-1 (2) and 24-methylenelanost-9(11)- en-3β-ol acetate (3) were assigned NMR data for the first time and compound 3 was obtained as a natural product from a plant for the first time. 相似文献
59.
Nitin K SAKSENA Bin WANG Megan STEAIN Rong Ge YANG Lin Qi ZHANG 《Cell research》2005,15(11):953-961
Several reviews have focused on the nature of HIV infection and its spread in various geographical regions of China. In contrast, this review provides a comprehensive update on the prevalence of multiple HIV- 1 subtypes, consequent emergence of recombinant and novel forms of HIV- 1 in China, and the implications this may have on HIV diversity and the development of effective vaccines. In addition it also examines the dissemination of primary drug resistance in therapy naive patients, as well as co-infections with two other important viruses-hepatitis B and C. The main purpose of this review is to provide a current snapshot of HIV-1 pathogenesis in China and possibly shed some light on the future of HIV evolution, and potential challenges for future vaccine and anti-retroviral therapeutics against HIV strains in this area. 相似文献
60.
Wen-Bin JIANG Ma HAKIM Lei LUO Bo-Wen LI Shi-Long YANG Yu-Zhu SONG Ren LAI Qiu-Min LU 《动物学研究》2015,36(3):174-177
As a group of intestinal hormones and neurotransmitters, cholecystokinins(CCKs) regulate and affect pancreatic enzyme secretion, gastrointestinal motility, pain hypersensitivity, digestion and satiety, and generally contain a DYMGWMDFG sequence at the C-terminus. Many CCKs have been reported in mammals. However, only a few have been reported in amphibians, such as Hyla nigrovittata, Xenopus laevis, and Rana catesbeiana, with none reported in urodele amphibians like newts and salamanders. Here, a CCK called CCK-TV was identified and characterized from the skin of the salamander Tylototriton verrucosus. This CCK contained an amino acid sequence of DYMGWMDF-NH2 as seen in other CCKs. A c DNA encoding the CCK precursor containing 129 amino acid residues was cloned from the c DNA library of T. verrucosus skin. The CCK-TV had the potential to induce the contraction of smooth muscle strips isolated from porcine gallbladder, eliciting contraction at a concentration of 5.0x10-11 mol/L and inducing maximal contraction at a concentration of 2.0x10-6 mol/L. The EC50 was 13.6 nmol/L. To the best of our knowledge, this is the first report to identify the presence of a CCK in an urodele amphibian. 相似文献