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1.
Limited genetic information is available concerning the polymorphisms of HIV-1 resistant genes in indigenous Chinese populations. The aim of this study is to identify the allelic frequencies of the chemokine and chemokine receptor genes in the Chinese mainland. Genomic DNA samples extracted from whole blood of 2318 subjects were analyzed by using PCR or PCR/restriction fragment length polymorphism (RFLP) assays, and further confirmed by direct DNA sequencing. Higher frequencies of mutant CCR2-64I (19.15%—28.79%) and SDF1-3’A (19.10%—29.86%) alleles were found in subjects of 8 ethnic groups in the Chinese mainland. In contrast, the △32 mutation in CCR5 gene occurs at a very low frequency (0.0016, n=1287) in Han population. A relatively high frequency of CCR5- wt/D32 heterozygotes was observed in Uygurian and Mongolian populations. No △32 mutation allele was detected in Tibetan and other 4 ethnic groups in Yunnan Province. There was no CCR5-m303 mutation in subjects of any ethnic group in the Chinese mainland. Our results suggest that the CCR5-△32 mutation is not a major resistant factor against HIV-1 infection and disease progression in Han, Tibetan and other ethnic groups in Yunnan Province. Whether higher frequencies of CCR2-64I and SDF1-3′A alleles constitute major genetic resistant factors or not remains to be clarified.  相似文献   

2.
Using cDNA microarray hybridization from a human testicular cDNA library, one gene exhibiting ten-fold difference at expression level between adult and embryo human testes was cloned and named NYD-SP9, which was believed to be involved in spermatogenesis. Southern blot hybridization results showed that NYD-SP9 expressed highly in testis but low in ovary. Protein motif analysis of this cDNA sequence revealed a cluster of phosphorylation sites, indicating its potential involvement in signal pathways during spermatogenesis. Furthermore, one transmembrane helix was predicted in N-terminal region, indicating that putative NYD-SP6 may be served as a transmembrane protein. The proximity of these potential phosphorylation sites to each other indicates that there may be interaction among these sites to regulate spermatogenesis. These findings suggested that protein kinase NYD-SP9 might play a role in male germ cell differentiation.  相似文献   

3.
Lau WC  Rubinstein JL 《Nature》2012,481(7380):214-218
Ion-translocating rotary ATPases serve either as ATP synthases, using energy from a transmembrane ion motive force to create the cell's supply of ATP, or as transmembrane ion pumps that are powered by ATP hydrolysis. The members of this family of enzymes each contain two rotary motors: one that couples ion translocation to rotation and one that couples rotation to ATP synthesis or hydrolysis. During ATP synthesis, ion translocation through the membrane-bound region of the complex causes rotation of a central rotor that drives conformational changes and ATP synthesis in the catalytic region of the complex. There are no structural models available for the intact membrane region of any ion-translocating rotary ATPase. Here we present a 9.7?? resolution map of the H(+)-driven ATP synthase from Thermus thermophilus obtained by electron cryomicroscopy of single particles in ice. The 600-kilodalton complex has an overall subunit composition of A(3)B(3)CDE(2)FG(2)IL(12). The membrane-bound motor consists of a ring of L subunits and the carboxy-terminal region of subunit I, which are equivalent to the c and a subunits of most other rotary ATPases, respectively. The map shows that the ring contains 12 L subunits and that the I subunit has eight transmembrane helices. The L(12) ring and I subunit have a surprisingly small contact area in the middle of the membrane, with helices from the I subunit making contacts with two different L subunits. The transmembrane helices of subunit I form bundles that could serve as half-channels across the membrane, with the first half-channel conducting protons from the periplasm to the L(12) ring and the second half-channel conducting protons from the L(12) ring to the cytoplasm. This structure therefore suggests the mechanism by which a transmembrane proton motive force is converted to rotation in rotary ATPases.  相似文献   

4.
Gene mapping of a mouse coat mutation has been investigated. First, 100 10-bp random primers were used to amplify DNA, but the mutation could not be located by this method because there were no correlation between the amplified products and coat phenotypes. Second, by usingIdh1, Car2, Mup1, Pgb1, Hbb, Es10, Es1, Mod1, Gdc1, Ce2, Es3 as genetic markers, linkage test crosses (two-point test) consisting of intercrossing uncovered BALB/c mice (homozygotes) to CBA/N and C57BV6 mice with normal hair and backcrossing the heterozygotes of the F1 to the uncovered BALB/c mice were made. It was soon evident that the mutation was linked toEs3 on chromosome 11. Furthermore, three-point test was made by usingEs3 and D11Mit8 (a microsatellite DNA) as genetic markers. The result showed that the mutation was linked toEs3 with the percentage recombination of (7.89 ± 2.19)%, and linked to Dl1Mit8 with the percentage recombination of (26.30± 3.57)%. The percentage recombination betweenEs3 and D11Mit8 was (32.90±3.81)%. The mutation was named Uncovered, with the symbolUncv. According to the recombinations, the loci order was D11Mit8-26.30±3.57-Uncv- 7.89 -2.19-Es3. From the location on the chromosome, it was concluded that the mutation was a new mutation which affected the skin and hair structure of mouse. TheUncv has entered MGD (Mouse Genome Database).  相似文献   

5.
6.
异色瓢虫的HSP90基因的克隆与特性分析   总被引:1,自引:0,他引:1  
采用同源克隆和锚定PCR技术,从异色瓢虫Harmonia axyridis(Pallas)中克隆到热休克蛋白HSP90基因的cDNA全序列(Genbank number:FJ501962)。cDNA全长2 480 bp,包含3′非编码区域(UTR)为200 bp和5′UTR为126 bp,开放阅读框(ORF)长2 154 bp,编码717个氨基酸。预测的相对分子质量为82 230,理论等电点为4.96,无糖基化位点、跨膜结构和信号肽。在N端具有HSP90基因保守的ATPase结构,含有HSP90家族的C末端的保守序列EEVD。与赤拟谷盗Tribolium castaneum相比较,同源性高达90%,系统发育分析也表明两者的亲缘关系最近。HaaHSP90基因的克隆和比较分析为进一步深入研究异色瓢虫的抗逆机理及其进化具有重要意义。  相似文献   

7.
The cDNA encoding hsc70 of Chinese shrimp Fenneropenaeus chinensis was cloned from hepatopancreas by RT-PCR based on its EST sequence. The full length cDNA of 2090 bp contained an open reading frame of 1956 nucleotides and partial 5‘- and 3‘-untranslated region(5‘- and 3‘-UTR). PCR amplification and sequencing analysis showed the existence of introns in the region of 1--547 bp, but they did not exist in the region of 548--2090 bp of hsc70 cDNA. When the deduced 652 amino acid sequence of HSC70 was compared with the members of HSP70 family from other organisms, the results showed 85.9% similarity with HSC71 from Oncorhynchus mykiss and HSC70 from Homo sapiens. It also exhibited 85.8% similarity with HSP70 from Mus musculu and 85.4% with HSC70 from Manduca sexta. Expression analysis showed that hsc70 mRNA was espressed constitutively in hepatopancreas, muscle, eyestalks, haemocytes, heart, ovary, intestine and gills in Fenneropenaeus chinensis. No difference could be detected on hsc70 mRNA level in muscle between heat-shocked and control animals.  相似文献   

8.
Several vanadium compounds have been known for the hypoglycemic and anticancer effects. However, the mechanisms of the pharmacological and toxicological effects were not clear. In this work, we in- vestigated the potential targets of vanadium in mitochondria. Vanadyl ions were found to bind to mi- tochondria from rat liver with a stoichiometry of 244±58 nmol/mg protein and an apparent dissocia- tion constant (Kd) of (2.0±0.8)×10·16 mol/L. Using size exclusion chromatography, a vanadium-binding protein was isolated and identified to be the 60-kDa heat shock protein (HSP60) by mass spectrometry analysis and immunoassays. Additionally, binding of vanadyl ions was found to result in depolymeri- zation of homo-oligomeric HSP60 (GroEL). HSP60 is an indispensable molecular chaperone and in- volved in many kinds of pathogenesis of inflammatory and autoimmune diseases, e.g. type 1 diabetes. Our results suggested that HSP60 could be a novel important target involved in the biological and/or toxicological effects of vanadium compounds.  相似文献   

9.
A total of 26718 M1 plants were ob- tained by crossing the active mutator transposon donor parents (Q105, WW51, 115F, V26-2 and 919J) with the recipient parents (Hz85,W328 with Bz gene and S-Mo17Rf3Rf3). The phenotypes of M1 plants were observed in the field. M1 plants were self-pollinated to develop the mutator insertion-mutagenized M2 seeds. The transposition frequency of the mutator in the genome was calculated based on the spotted aleurone phenotype of the M2 seeds. The results showed that: (1) the mutation frequency of M1 phe- notypes in the field was 0.07 in the population of W328×Mu; (2) the mutation frequency of spotted aleurone seeds on the M2 ears was 0.122 in the population of W328×Mu; (3) five S-cytoplasm male-sterile plants were found among 22500 M1 plants of S-Mo17Rf3Rf3×Mu, with the transposition frequency about 2.2×10?4 per locus. 99 flanking se- quences of mutator transposition were amplified by the modified MuTAIL-PCR, and 59 non-redundant sequences with length around 400 bp were obtained. After bioinformatic analysis, 27 sequences of them could be annotated, using non-redundant nucleotide database of maize, rice, and Arabidopsis. 36 se- quences of them were located on the genetic map of maize by comparative genomics, and several flank- ing sequences of mutator insertion were mapped on the single marker locus. Hotspot sequences of mu- tator transposition were revealed by comparing the homologies between the 9-bp target site duplication of the mutator insertion. The putative functions of 8 flanking sequences of mutator transposition had identity with the functions of their correspondingmarker. The constructed mutator insertion mutant population in maize will facilitate the new gene discovery and functional genomics study in maize.  相似文献   

10.
11.
The expression ofWnt, Wntreceptor-Frizzled, and several other key components in Wnt pathway in renal cancer cell lines was studied. The result of semi-quantitative RT-PCR has shown that the expression level ofWnt5A andhFz5 mRNA were higher in renal cancer cell line (GRC-1) than in normal renal cell line (HK-2). This result has been confirmed byin situ hybridization. The expression of β-catenin protein was obviously higher in GRC-1 than in HK-2 (P< 0.01), but there were no different expressions of its mRNA between 3 lines. The reasons of the overexpression of β-catenin has been investigated by means of immunocytochemistry, SSCP and so on, no mutation ofβ-catenin gene and APC were found. That means that the overexpression ofWnt5A/hFz5 might be the reason of overexpression of β-catenin. It was concluded that the aberrant activity of Wnt pathway might play an important role in renal cell carcinoma.  相似文献   

12.
 采用同源克隆和锚定PCR技术, 从异色瓢虫 Harmonia axyridis (Pallas)中克隆到热休克蛋白HSP 90 基因的cDNA全序列(Genbank number: FJ501962)。cDNA全长2 480 bp,包含3′非编码区域(UTR)为200 bp和5′UTR为126 bp,开放阅读框(ORF) 长2.154 bp,编码717个氨基酸。预测的相对分子质量为82.230, 理论等电点为4.96,无糖基化位点、跨膜结构和信号肽。在N端具有 HSP 90 基因保守的ATPase结构,含有HSP90家族的C末端的保守序列EEVD。与赤拟谷盗 Tribolium castaneum 相比较,同源性高达90%,系统发育分析也表明两者的亲缘关系最近。 HaaHSP 90 基因的克隆和比较分析为进一步深入研究异色瓢虫的抗逆机理及其进化具有重要意义。  相似文献   

13.
A gene encoding a cysteine proteinase was isolated from senescent leave of cotton (Gossypium hirsutum) cv liaomian No. 9 by utilizing rapid amplification of cDNA end spolymerase chain reaction (RACE-PCR), and a set of consensus oligonucleotide primers was designed to anneal the conserved sequences of plant cysteine protease genes. The cDNA, which designated Ghcysp gene, contained 1368 bp terminating in a poly(A)^ trail, and included a putative 5‘(98 bp) and a 3‘(235 bp) non-coding region. The opening reading frame (ORF) encodes polypeptide 344 amino acids with the predicted molecular mass of 37.88 kD and theoretical pl of 4.80. A comparison of the deduced amino acid sequence with the sequence in the GenBank database has shown considerable sequence similarity to a novel family of plant cysteine proteases. This putative cotton Ghcysp protein shows from 67% to 82% identity to the other plants. All of them share catalytic triad of residues, which are highly conserved in three regions. Hydropaths analysis of the amino acid sequence shows that the Ghcysp is a potential membrane protein and localizes to the vacuole, which has a transmembrane helix between resides 7-25. A characteristic feature of Ghcysp is the presence of a putative vacuole-targeting signal peptide of 19-amino acid residues at the N-terminal region. The expression of Ghcysp gene was determined using northern blot analysis. The Ghcysp mRNA levels are high in development senescent leaf but below the limit of detection in senescent root, hypocotyl, faded flower, 6 d post anthesis ovule, and young leaf.  相似文献   

14.
Based on field runoff plots observation and sample analysis, the effect of slope gradient on soil organic carbon loss was studied under natural rainfall conditions in loess hilly region. The results showed that with slope gradient increasing (from10° to 30°), the changing trend of soil erosion intensity (A) was A20°〉A30°〉A15°〉A10°〉A25°, suggesting that slope gradient between 20° and 25° was a critical degree ranger to exist. Soil organic carbon loss was mainly influenced by soil erosion intensity, appearing the same trend as did soil erosion intensity with increasing slope gradient. Soil erosion results in organic carbon enrichment in sediment. Average enrichment ratios of five runoff plots varied from 2.27 to 3.74, and decreased with increasing erosion intensity and slope gradient. The decrease of surface runoff and soil erosion is the key to reduce soil organic carbon loss.  相似文献   

15.
采用减压分馏的方法对油樟叶精油进行分馏,结合GC-MS联用技术研究油樟叶精油及其不同馏分的化学成分,并对其清除1,1-二苯-2-三硝基苯肼(DPPH)自由基能力进行了评价。结果表明:油樟叶精油及其不同馏分中的化学成分及其含量差异较显著。从油樟叶精油(A_0号精油)及其所得到的馏分(A_1号精油、A_2号精油、A_3号精油)中分别鉴定出29、15、20和31种物质,共鉴定出31种化合物,包括烃类21种、醇类8种、酮类和酯类各1种,它们的共有成分有15种,此外还检测到一些特有成分,油樟叶精油(A_0号精油)14种、馏分A_2号精油5种、馏分A_3号精油16种。油樟叶精油及其不同馏分均有清除DPPH自由基能力,它们的抗氧化活性能力强弱顺序为A_3 A_2 A_0 A_1。但它们清除能力均低于同质量浓度的维生素C。本研究结果为油樟叶精油有效成分的进一步分离纯化及其资源开发利用可以提供理论依据。  相似文献   

16.
汤宏赤  莫莉  闭海  林丽华  郭媛  庞浩  ** 《广西科学》2019,26(4):410-416
本研究对具有大分子水解能力的环糊精水解酶cds1-3的蛋白结构进行分析,选取底物通道相关氨基酸进行定点突变。通过比较突变酶和野生酶的功能差异,定位决定cds1-3特殊功能的氨基酸。采用sybyl 1.2进行蛋白质底物结合分析,选取和多聚体形成、底物结合以及底物通道相关的氨基酸Glu66、Pro48、Phe289为突变位点,反向PCR构建pSE380/E66G、pSE380/P48H、pSE380/F289A表达质粒并进行表达,获得酶活突变体并与原始酶进行底物特异性比较分析。其结果显示,突变酶E66G降解大分子底物木薯淀粉和支链淀粉的相对酶活力分别提高26.96%和23.15%,而对小分子底物普鲁兰糖的水解能力下降13.14%。因此,cds1-3是一个能水解大分子底物的特殊环糊精水解酶,氨基酸Glu66是cds1-3水解大分子支链淀粉的关键氨基酸之一。  相似文献   

17.
Researches on Candidal heat-shock protein 90 (HSP90) in recent years are summarized.Candida albicans is a commensal pathogen in human and animals. In immunocompromised individuals it behaves as an opportunist pathogen, giving rise to superficial or systemic infections. Systemic candidosis is a common cause of death among immunocompromised and debilitated patients, in which the mortality is as high as 70%. HSP90 is now recognized as an immunodominant antigen inC. albicans and plays a key role in systemic candidosis as a molecular chaperone. The 47-ku peptide is the breakdown product of HSP90. Patients who has recovered from systemic candidosis produce high titre of antibodies to 47-ku antigen, whereas the fatal cases have little antibody or falling titres. The three commonest epitopes of candidal HSP90 have been mapped, epitopes C, B and H. Epitopes C and H are immunogenic. The antibody probes of both epitopes may be developed into a new serological test agents for systemic candidosis due to rather high specificity and sensitivity. The recent results establish HSP90 as an ATP-dependent chaperone that is involved in the folding of cell regulatory proteins and in the refolding of stress-denatured polypeptides. Some researches on fungal HSP90 and the treatment of patients with candidosis are reviewed as well.  相似文献   

18.
Heterotrimeric G-proteins consisting of α, β and γ-subunits are essential for the transduction of ex- tracellular signals to various downstream intracellular effectors in eukaryotes. Previous studies showed that Gα and Gβ were involved in regulating  相似文献   

19.
A magnetosome-deleted mutant NM21 of Magnetospirillum gryphiswaldense MSR-1 was generated by mini-Tn5 lacZ2 transposon mutagenesis, and a 3073-bp fragment flanking mini-Tn5 lacZ2 in NM21 was cloned by Anchored PCR. Sequencing analysis showed that this fragment involved three putative ORFs; the mini-Tn5 lacZ2 was inserted into ORF1. Functional complementary test indicated that the 3073-bp fragment was required for biosynthesis of magnetosomes in M. gryphiswaldense MSR-1. The majority of proteins, which had homology with the protein encoded by ORF1, were the cation transporter. Transmembrane domain analysis showed that the protein encoded by ORF1 contained four transmembrane domains. It may be a transmembrane protein. The protein encoded by ORF1 contained two putative conserved domains: COG0053 and PRK09509. The MMT1 and FieF, containing conserved domains COG0053 and PRK09509 too, were Fe2+ transporter (cation diffusion facilitator superfamily). It was suggested that the protein encoded by ORF1 might take part in the magnetosomes biosynthesis as Fe2+ transporter. Supported by National Natural Science Foundation of China (Grant No. 30570023) and Scientific Research Project of Huaibei City, Anhui Province (Grant No. 070114)  相似文献   

20.
A mRNA preferentially expressed in cotton fiber was cloned from fiber total RNA of normal upland cotton TM-1 (wild-type) by using RT-PCR and corresponding cDNA (signed as TM-E6) was sequenced. TM-E6 gene had no intron and contained an open reading frame of 771 bp long, and might encode a peptide of 246 amino acids. Other 4 genes, Fl-E6, Li-E6, N-E6 and Bl-E6, which were homologous to TM-E6 gene, were also isolated from 4 fiber mutants of Fiberless Xu-zhou 142, Ligon lintless, Naked seed and Brown lint, respectively. Sequence analysis of each of these mutant genes revealed many variations in structure and nucleotide composition of gene when compared with the sequence of TM-E6 gene. (ⅰ) There was a changeable repetitive segment in which GGCTCA (Gly-Ser) was repeated 3—5 times between the 82nd and the 93rd codons in different mutant genes. Since the change of Gly-Ser repetitive segment occurred not only in the mutants but also in the wild-type cotton, the repeat frequency might not be associated with the mutation of fiber characteristics. (ⅱ) Among the 4 mutant genes, the percentage of changed codons was 7.05% in Fl-E6, 4.98% in Li-E6, and 4.15% in N-E6 and Bl-E6. It seems that the percentage of changed codons in E6 sequence was positively correlated to the degree of fiber morphological variation. (ⅲ) E6 polypeptides of two long-fiberless mutants (Fiberless Xuzhou 142 and Ligon lintless) contained high similar (99.4%) variation in the region of 1—174 amino acids from N-terminus, and those of short-fiberless mutants (Fiberless Xuzhou and naked seed) revealed identical variation in the region of 116th—220th amino acids. It also seems that there was a parallel relation between E6 protein variation and fiber phenotype mutation. (ⅳ) Li-E6 and Bl-E6 genes also expressed at low level in seed coat besides at high level in fiber.  相似文献   

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