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1.
In an effort to localize a gene for ataxia-telangiectasia (A-T), we have genotyped 27 affected Costa Rican families, with 13 markers, in the chromosome 11q22-23 region. Significant linkage disequilibrium was detected for 9/13 markers between D11S1816 and D11S1391. Recombination events observed in these pedigrees places A-T between D11S1819 and D11S1960. One ancestral haplotype is common to 24/54 affected chromosomes and roughly two-thirds of the families. Inferred (ancestral) recombination events involving this common haplotype in earlier generations suggest that A-T is distal to D11S384 and proximal to D11S1960. Several other common haplotypes were identified, consistent with multiple mutations in a single gene. When considered together with all other evidence, this study further sublocalizes the major A-T locus to ≈200 kb, between markers S384 and S535.  相似文献   
2.
色盲是一种遗传性疾病,由于色觉机理尚未研究清楚,一向不能矫治。为了解除色盲患者的苦脑,增加他们在升学、就业和职业选择中的权利,我们通过色觉过程的拓扑学研究,建立了色觉异常的突变模型;论证了色盲矫治机理;研制了色盲电脑诊断矫正检测仪。为色盲眼镜的批量生产和患者的配镜提供准确的矫正曲线。  相似文献   
3.
对1例新型冠状病毒肺炎疫情流行早期的无症状感染者临床标本进行SARS-CoV-2实验室鉴定和全基因组测定,在分子水平了解新型病毒的基因特点和变异情况,追溯病毒潜在来源.实时荧光定量PCR扩增丽水市庆元县首例确诊患者密切接触者的痰液标本SARS-CoV-2核酸,阳性RNA逆转录为cDNA构建文库后进行基于NGS的宏基因组深度测序,生物学软件分析处理数据.该密接无任何症状及体征,痰液标本SARS-CoV-2核酸阳性.测序数据包含有足够的病毒序列,组装成功后hCoV-19/Lishui/LS556/2020长29 887bp,G+C含量37.99%,在ORF1ab和N区域发现4个SNP,对应1个错义突变和3个同义突变.LS556与SARS-CoV-2参考序列核苷酸/氨基酸同源性在99.2%/97.4%以上,不同序列之间存在4~17个核苷酸差异,与蝙蝠病毒RaTG13核苷酸差异仅3.7%,存在1141个SNP,与穿山甲病毒Guangdong/1相似性90.9%.LS556属于β冠状病毒Lineage B谱系,与LS003和ZJU-06共享完全相同的病毒,与蝙蝠/穿山甲冠状病毒进化上最相关.结合流行病学、核酸诊断、病毒溯源判定其为无症状感染者.LS556组成和结构符合SARS-CoV-2典型的基因特征,为高覆盖率序列,在流行早期与其他SARS-CoV-2基因组具有高度的同一性,突变率保持在较低水平,多数导致氨基酸位点保守置换.  相似文献   
4.
Growing evidence from epidemiological studies indicates the association between rheumatoid arthritis (RA) and measles. However, the exact mechanism for this association is still unclear now. We consider that the strong association between both diseases may be caused by shared genetic pathways. We performed a pathway analysis of large-scale RA genome-wide association studies (GWAS) dataset with 5,539 cases and 20,169 controls of European descent. Meanwhile, we evaluated our findings using previously identified RA loci, protein-protein interaction network and previous results from pathway analysis of RA and other autoimmune diseases GWAS. We confirmed four pathways including Cytokine-cytokine receptor interaction, Jak-STAT signaling, T cell receptor signaling and Cell adhesion molecules. Meanwhile, we highlighted for the first time the involvement of Measles and Intestinal immune network for IgA production pathways in RA. Our results may explain the strong association between RA and measles, which may be caused by the shared genetic pathway. We believe that our results will be helpful for future genetic studies in RA pathogenesis and may significantly assist in the development of therapeutic strategies.  相似文献   
5.
The vitamin D receptor (VDR) principally mediates the anticancer activities of vitamin D. Various epidemiological studies have investigated the associations of VDR gene polymorphisms with ovarian cancer; however, the results have been inconclusive. In the current study, we evaluated, in a meta-analysis, the association of five common single nucleotide polymorphisms (SNPs) in the VDR gene (ApaI, BsmI, Cdx-2, FokI, and TaqI) with the risk of ovarian cancer. Six eligible studies, with a total of 4,107 cases and 6,661 controls, which evaluated the association of these variants and ovarian cancer risk, were identified from the MEDLINE and PubMed databases. The meta-analysis indicated that FokI was associated with an increased ovarian cancer risk, with a pooled odds ratio (OR) of 1.10 [95% confidence intervals (95% CI) = 1.00–1.20] for CT heterozygotes and 1.16 (95% CI = 1.02–1.30) for TT homozygotes relative to common CC carriers. Carriers of the T allele (also known as the f allele) showed an 11% (pooled OR = 1.11, 95% CI = 1.02–1.21; TT/CT vs. CC) increased risk of ovarian cancer relative to CC carriers. For FokI, no significant heterogeneity between the studies was found (I2 = 0%, P = 0.62 for the Q test). There was no statistically significant association between the other four variants (ApaI, BsmI, Cdx-2 and TaqI) and risk of ovarian cancer. These data indicate that the polymorphism FokI on the VDR is a susceptibility factor for ovarian cancer. Nevertheless, more studies are warranted to elucidate the underlying mechanisms of the VDR in development of ovarian cancer.  相似文献   
6.
The stress-responding protein, GADD45α, plays important roles in cell cycle checkpoint, DNA repair and apoptosis. In our recent study, we demonstrate that GADD45α undergoes a dynamic ubiquitination and degradation in vivo, which process can be blocked by the cytotoxic reagent, arsenite, resulting in GADD45α accumulation to activate JNKs cell death pathway, thereby revealing a novel mechanism for the cellular GADD45α functional regulation. But the factors involved in GADD45α stability modulations are unidentified. Here, we demonstrated that MDM2 was an E3 ubiquitin ligase for GADD45α. One of MDM2-binding partner, ribosomal protein S7, interacted with and stabilized GADD45α through preventing the ubiquitination and degradation of GADD45α mediated by MDM2. This novel function of S7 is unrelated to p53 but seems to depend on S7/MDM2 interaction, for the S7 mutant lacking MDM2-binding ability lost its function to stabilize GADD45α. Further investigations indicated that arsenite treatment enhanced S7–MDM2 interaction, resulting in attenuation of MDM2-dependent GADD45α ubiquitination and degradation, thereby leading to GADD45α-dependent cell death pathway activation. Silencing S7 expression suppressed GADD45α-dependent cytotoxicity induced by arsenite. Our findings thus identify a novel function of S7 in control of GADD45α stabilization under both basal and stress conditions and its significance in mediating arsenite-induced cellular stress.  相似文献   
7.
Integrins are heterodimeric transmembrane receptors that physically link the extracellular matrix (ECM) to the intracellular actin cytoskeleton, and are also signaling molecules that transduce signals bi-directionally across the plasma membrane. Integrin regulation is essential for tumor cell migration in response to growth factors. c-Abl kinase is a nonreceptor tyrosine kinase and is critical for signaling transduction from various receptors. Here we show that c-Abl kinase is involved in A375 cell migration mediated by αvβ3 integrin in response to PDGF stimulation. c-Abl kinase colocalizes with αvβ3 integrin dynamically and affects αvβ3 integrin affinity by regulating its cluster. The interaction between c-Abl kinase and αvβ3 integrin was dependent on the activity of c-Abl kinase induced by PDGF stimulation, but was not dependent on the binding of αvβ3 integrin with its ligands, suggesting that c-Abl kinase is not involved in the outside-in signaling of αvβ3 integrin. Talin head domain was required for the interaction between c-Abl kinase and αvβ3 integrin, and the SH3 domain of c-Abl kinase was involved in its interaction with talin and αvβ3 integrin. Taken together, we have uncovered a novel and critical role of c-Abl kinase in αvβ3 integrin mediated melanoma cell migration.  相似文献   
8.
The transgenic Bt cotton plant has been widely planted throughout the world for the control of cotton budworm Helicoverpa armigera (Hubner). However, a shift towards insect tolerance of Bt cotton is now apparent. In this study, the gene encoding neuropeptide F (NPF) was cloned from cotton budworm H. armigera, an important agricultural pest. The npf gene produces two splicing mRNA variants—npf1 and npf2 (with a 120‐bp segment inserted into the npf1 sequence). These are predicted to form the mature NPF1 and NPF2 peptides, and they were found to regulate feeding behaviour. Knock down of larval npf with dsNPF in vitro resulted in decreases of food consumption and body weight, and dsNPF also caused a decrease of glycogen and an increase of trehalose. Moreover, we produced transgenic tobacco plants transiently expressing dsNPF and transgenic cotton plants with stably expressed dsNPF. Results showed that H. armigera larvae fed on these transgenic plants or leaves had lower food consumption, body size and body weight compared to controls. These results indicate that NPF is important in the control of feeding of H. armigera and valuable for production of potential transgenic cotton.  相似文献   
9.
A series of SrMoO4:Sm3+,Tb3+,Na+ phosphors was synthesized using a high‐temperature solid‐state reaction method in air. On excitation at 290 nm, SrMoO4:Sm3+,Tb3+ phosphor emitted light that varied systematically from green to reddish‐orange on changing the Sm3+ and Tb3+ ion concentrations. The emission intensities of SrMoO4:Sm3+ and SrMoO4:Sm3+,Tb3+ phosphors were increased two to four times due to charge compensation when Na+ was added as a charge compensator. The luminescence mechanism and energy transfer could be explained using energy‐level diagrams of the MoO42– group, Sm3+ and Tb3+ ions. SrMoO4:Sm3+,Tb3+,Na+ could be used as reddish‐orange phosphor in white light‐emitting diodes (LEDs) based on an ~ 405 nm near‐UV LED chip. This research is helpful in adjusting and improving the luminescence properties of other phosphors. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
10.
Verticillium dahliae infection leads to Verticillium wilt in cotton and other dicotyledon crops. To reduce the loss of economic crops, more attention has been focused on the key genes involved in pathogenicity of this soil‐borne plant fungal pathogen. Sho1 encodes a conserved tetraspan transmembrane protein which is a key element of the two upstream branches of the HOG‐MAPK pathway in fungi. Sho1 is required for full virulence in a wide variety of pathogenic fungi. In this study, sho1 mutant in V. dahliae (designated ΔVdsho1) was generated by Agrobacterium tumefaciens‐mediated transformation. ΔVdsho1 strain was highly sensitive to menadione (at concentration of 120 μm ) and hydrogen peroxide (at concentration of 250 μm ), displayed delayed spore germination and reduced spore production compared with the wild type and the complemented strains. During infection of host cotton plants, ΔVdsho1 exhibited impaired ability of root attachment and invasive growth. Results from the present work suggest that VdSho1 controls external sensing, virulence and multiple growth‐related traits in V. dahliae and might serve as a potential target for control of Verticillium wilt.  相似文献   
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