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61.
62.
We have broadly defined the DNA regions regulating esterase6 activity in
several life stages and tissue types of D. melanogaster using P-
element-mediated transformation of constructs that contain the esterase6
coding region and deletions or substitutions in 5' or 3' flanking DNA.
Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and
the primary sequences regulating its activity lie between -171 and -25 bp
relative to the translation initiation site: deletion of these sequences
decrease activity approximately 20-fold. Hemolymph activity is also
modulated by four other DNA regions, three of which lie 5' and one of which
lies 3' of the coding region. Of these, two have positive and two have
negative effects, each of approximately twofold. Esterase6 activity is
present also in two male reproductive tract tissues; the ejaculatory bulb,
which is another ancestral activity site, and the ejaculatory duct, which
is a recently acquired site within the melanogaster species subgroup.
Activities in these tissues are at least in part independently regulated:
activity in the ejaculatory bulb is conferred by sequences between -273 and
-172 bp (threefold decrease when deleted), while activity in the
ejaculatory duct is conferred by more distal sequences between -844 and
-614 bp (fourfold decrease when deleted). The reproductive tract activity
is further modulated by two additional DNA regions, one in 5' DNA (-613 to
-284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to
+2731 bp; threefold decrease when deleted) that probably overlaps the
adjacent esteraseP gene. Collating these data with previous studies
suggests that expression of EST6 in the ancestral sites is mainly regulated
by conserved proximal sequences while more variable distal sequences
regulate expression in the acquired ejaculatory duct site.
相似文献
63.
复方克痛宁临床应用镇痛效果 总被引:3,自引:0,他引:3
应用复方克痛宁注射液,治疗各种痛证82例,显效50%,有效43.9%,总有效率93.9%。其中大多数病例都是经用其它药或疗法无效或效差而用本药获效的。对关节痛、神经血管性头痛等顽固性疼痛显著独特。用药次数最少1次,最多35例,仅极个别有轻微短暂口干、头晕副作用,各项常规化验检查均无异常,效果显著高于克痛宁或盐酸平痛新单用。临床应用的结果与动物试验观察到的协同增效结果一致。 相似文献
64.
丙型肝炎病毒基因组部份NS5区蛋白基因在大肠杆菌中的表达 总被引:1,自引:0,他引:1
在大肠杆菌中表达了丙型肝炎病毒基因组NS5区A段和部份B段蛋白。NS5A蛋白溶于水,可经过GST亲和层析柱纯化;NS5B蛋白不溶于水,经PBS-Triton X-100洗涤,尿素溶解后,通过离子交换柱纯化。经SDS-PAGE和Westemblot分析,NS5A蛋白除在57kD左右有条带外,还有不同程度的降解产物;NS5B蛋白主要在58kD左右有条带出现。为查明表达蛋白抗体在病人血清中的分布,取9 相似文献
65.
本文将昆明地区11-15岁健康儿童90名按不同的口腔条件分为三组,每组30人。采用培养基表面主培养主数法,分别测定唾液中厌氧菌和需氧菌细菌总数。结果表明:儿童唾液中细菌总数,牙颌畸形组、正畸组、正常组,三组间结果在统计学无显著差异。 相似文献
66.
Transformation of Mycoplasma gallisepticum with Tn916, Tn4001, and integrative plasmid vectors. 总被引:3,自引:1,他引:2
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Mycoplasma gallisepticum causes respiratory disease in avian species, but little is known about its mechanism(s) of pathogenesis. These studies were undertaken in order to develop genetic systems for analysis of potential virulence factors. M. gallisepticum was transformed with plasmids containing one of the gram-positive transposons Tn916 or Tn4001, which inserted randomly into the mycoplasmal chromosome. Plasmids containing cloned chromosomal DNA were also constructed and tested for integration into regions of DNA homology derived either from chromosomal fragments or from the gentamicin resistance marker from Tn4001. These studies demonstrate that M. gallisepticum is amenable to transformation with both transposons and integrative vectors. 相似文献
67.
Brucella abortus catalase is a periplasmic protein lacking a standard signal sequence. 总被引:3,自引:2,他引:1
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A periplasmic catalase has been purified and cloned from Brucella abortus. The functional enzyme is a tetramer with a subunit molecular weight of 55,000. All evidence indicates that a typical N-terminal signal sequence is not associated with the export of this protein to the periplasm. 相似文献
68.
Ying Cao Jun Adachi Axel Janke Svante Pääbo Masami Hasegawa 《Journal of molecular evolution》1994,39(5):519-527
The phylogenetic relationships among Primates (human), Artiodactyla (cow), Cetacea (whale), Carnivora (seal), and Rodentia (mouse and rat) were estimated from the inferred amino acid sequences of the mitochondrial genomes using Marsupialia (opossum), Aves (chicken), and Amphibia (Xenopus) as an outgroup. The overall evidence of the maximum likelihood analysis suggests that Rodentia is an outgroup to the other four eutherian orders and that Cetacea and Artiodactyla form a clade with Carnivora as a sister taxon irrespective of the assumed model for amino acid substitutions. Although there remains an uncertainty concerning the relation among Artiodactyla, Cetacea, and Carnivora, the existence of a clade formed by these three orders and the outgroup status of Rodentia to the other eutherian orders seems to be firmly established. However, analyses of individual genes do not necessarily conform to this conclusion, and some of the genes reject the putatively correct tree with nearly 5% significance. Although this discrepancy can be due to convergent or parallel evolution in the specific genes, it was pointed out that, even without a particular reason, such a discrepancy can occur in 5% of the cases if the branching among the orders in question occurred within a short period. Due to uncertainty about the assumed model underlying the phylogenetic inference, this can occur even more frequently. This demonstrates the importance of analyzing enough sequences to avoid the danger of concluding an erroneous tree. 相似文献
69.
Renu Tuteja Narendra Tuteja Franco Lilliu Bruno Bembi Renzo Galanello Antonio Cao Francisco E. Baralle 《Human genetics》1994,94(3):314-315
We report a novel mutation in exon 9 of the glucocerebrosidase gene of a patient with Gaucher disease and of Sardinian origin. 相似文献
70.
Chunyu Cao Hisao Kurazono Shinji Yamasaki Keiko Kashiwagi Kazuei Igarashi Yoshifumi Takeda 《Microbiology and immunology》1994,38(6):441-447
The gene encoding a Verotoxin 2 variant, VTvp1, was mutated by oligonucleotide-directed site-specific mutagenesis. Among 6 mutant toxins encoded by the mutated genes, E167Q-R170L (glutamic acid at position 167 and arginine at position 170 from N-terminus of the A subunit were replaced by glutamine and leucine, respectively) was found to have markedly decreased activities; inhibition of protein synthesis, Vero cell cytotoxicity and mouse lethality of the purified E167Q-R170L were 1/1,900, 1/125,000 and 1/2,000, respectively, of those of the purified wild-type VT2vp1. Since the antigenic property of the E167Q-R170L was demonstrated to be similar to that of the wild-type VT2vp1 by Ouchterlony double gel diffusion test and by neutralization test of Vero cell cytotoxicity of the VT2vp1, a possibility to use the mutant VT2vp1, E167Q-R170L, as a toxoid is discussed. 相似文献