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排序方式: 共有502条查询结果,搜索用时 15 毫秒
1.
Zabardast T. Buriev Sukumar Saha Ibrokhim Y. Abdurakhmonov Johnie N. Jenkins Abdusattor Abdukarimov Brian E. Scheffler David M. Stelly 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):587-606
MIC-3 is a recently identified gene family shown to exhibit increased root-specific expression following nematode infection of
cotton plants that are resistant to root-knot nematode. Here, we cloned and sequenced MIC-3 genes from selected diploid and tetraploid cotton species to reveal sequence differences at the molecular level and identify
chromosomal locations of MIC-3 genes in Gossypium species. Detailed sequence analysis and phylogenetic clustering of MIC-3 genes indicated the presence of multiple MIC-3 gene members in Gossypium species. Haplotypes of a MIC-3 gene family member were discovered by comparative analysis among consensus sequences across genotypes within an individual
clade in the phylogram to overcome the problem of duplicated loci in the tetraploid cotton. Deficiency tests of the SNPs delimited
six At-genome members of the MIC-3 family clustered to chromosome arm 4sh, and one Dt-genome member to chromosome 19. Clustering was confirmed by long-PCR amplification of the intergenic regions using At-genome-specific MIC-3 primer pairs. The clustered distribution may have been favored by selection for responsiveness to evolving disease and/or
pest pressures, because large variants of the MIC-3 gene family may have been recovered from small physical areas by recombination. This could give a buffer against selection
pressure from a broad range of pest and pathogens in the future. To our knowledge, these are the first results on the evolution
of clustering and genome-specific haplotype members of a unique cotton gene family associated with resistant response against
a major pathogen. 相似文献
2.
Transforming c-Ki-ras mutation is a preneoplastic event in mouse mammary carcinogenesis induced in vitro by N-methyl-N-nitrosourea. 总被引:2,自引:0,他引:2
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S Miyamoto S Sukumar R C Guzman R C Osborn S Nandi 《Molecular and cellular biology》1990,10(4):1593-1599
Mouse mammary epithelial cells can be transformed in primary cultures to preneoplastic and neoplastic states when treated with N-methyl-N-nitrosourea (MNU). Mammary carcinomas arising from MNU-induced hyperplastic alveolar nodules (a type of mouse mammary preneoplastic lesion) contained transforming c-Ki-ras genes when examined by the NIH 3T3 focus assay. Hybridization of allele-specific oligonucleotides to c-Ki-ras sequences amplified by the polymerase chain reaction demonstrated the presence of a specific G-35----A-35 point mutation in codon 12 in each of the NIH 3T3 foci as well as the mammary carcinomas. This mutation resulted in the substitution of the normal glycine with an aspartic acid. Furthermore, this mutation in the c-Ki-ras proto-oncogenes was also detected in 9 of 10 hyperplastic alveolar nodules. These results demonstrate that the specific c-Ki-ras mutation is a preneoplastic event in MNU-induced mouse mammary carcinogenesis. 相似文献
3.
The packing of peptide helices in crystals of the leucine-rich decapeptide Boc-Aib-Leu-Aib-Aib-Leu-Leu-Leu-Aib-Leu-Aib-OMe provides an example of ladder-like leucylleucyl interactions between neighboring molecules. The peptide molecule forms a helix with five 5----1 hydrogen bonds and two 4----1 hydrogen bonds near the C terminus. Three head-to-tail NH ... O = C hydrogen bonds between helices form continuous columns of helices in the crystal. The helicial columns associate in an antiparallel fashion, except for the association of Leu ... Leu side chains, which occurs along the diagonal of the cell where the peptide helices are parallel. The peptide, with formula C56H102N10O13, crystallizes in space group P2(1)2(1)2(1) with Z = 4 and cell parameters a = 16.774(3) A, b = 20.032(3) A and c = 20.117(3) A; overall agreement factor R = 10.7% for 2014 data with magnitude of F(obs) greater than 3 sigma (F); resolution 1.0 A. 相似文献
4.
S. Sukumar J. T. Hunter E. Yarkoni H. J. Rapp B. Zbar E. Lederer 《Cancer immunology, immunotherapy : CII》1981,11(2):125-129
Summary The effectiveness of each of two mycobacterial components and a synthetic analog of one of them in the eradication of pulmonary deposits of intravenously injected syngeneic fibrosarcoma 1023 in C3H mice was studied. BCG cell walls (BCG CW), trehalose 6,6-dimycolate (TDM) or 6,6-di-0-2-tetradecyl, 3-hydroxyoctadecanoyl-,-trehalose (C76), a synthetic analog of TDM, was administered in emulsified form by three different routes: intraperitoneal, intradermal, or intravenous, 24 h after intravenous injection of 1023 tumor cells. The most effective form of therapy was TDM given by the intraperitoneal route; about 50% of treated animals were cured. Higher doses of BCG CW or C76 also led to a significant number of cures. Each agent caused a significant prolongation of survival time of the treated mice at two or more of the dosages tested; however, their routes of optimal activity varied. 相似文献
5.
Summary Stable carbon isotope ratios in bone collagen have been used in a variety of dietary studies in modern and fossil animals,
including humans. Inherent in the stable isotope technique is the assumption that the isotopic signature is a reflection of
the diet and is persistent in collagen because this is a relatively inert protein. Carbon isotope analyses of bones from a
southern Indian population of Asian elephant (Elephas maximus), a long-lived mammal that alternates seasonally between a predominantly C3 (browse) and C4 (grass) plant diet, showed two patterns that have important implications for dietary interpretation based on isotopic studies.
Relative to the quantity of the two plant types consumed on average, the δ13C signal in collagen indicated that more carbon was incorporated from C3 plants, possibly due to their higher protein contribution. There was a much greater variance in δ13C values of collagen in sub-adult (range -10.5‰ to-22.7‰, variance=14.51) compared to adult animals (range -16.0‰ to -20.3‰,
variance=1.85) pointing to high collagen turnover rates and non-persistent isotopic signatures in younger, growing animals.
It thus seems important to correct for any significant relative differences in nutritive value of food types and also consider
the age of an animal before drawing definite conclusions about its diet from isotope ratios. 相似文献
6.
Bhagat Prakash Kumar Verma Deepanjali Sharma Deepika Sinha Alok Krishna 《Plant molecular biology》2021,107(1-2):117-127
Plant Molecular Biology - Cross-talk between light and ABA signaling is mediated by physical interaction between HY5 and ABI5 Arabidopsis. Plants undergo numerous transitions during their... 相似文献
7.
Udayawara Rudresh Deepika Maradagi Tehreem Stephen Nimish Mol Niraikulam Ayyadurai Nambi Ramudu Kamini Ponesakki Ganesan 《Molecular biology reports》2021,48(10):6923-6934
Molecular Biology Reports - The liver has a solid inbuilt antioxidant defense system to regulate oxidative stress. However, exposure to an excessive level of ROS causes liver injury. This study... 相似文献
8.
Pradyumna K. Mishra Gorantla V. Raghuram Hariom Panwar Deepika Jain Hemant Pandey Kewal K. Maudar 《Free radical research》2013,47(8):718-728
The role of oxidative stress is often attributed in environmental renal diseases. Isocyanates, a ubiquitous chemical group with diverse industrial applications, are known to undergo bio-transformation reactions upon accidental and occupational exposure. This study delineates the role of isocyanate-mediated mitochondrial oxidative stress in eliciting chromosomal instability in cultured human kidney epithelial cells. Cells treated with 0.005 µM concentration of methyl isocyanate displayed morphological transformation and stress-induced senescence. Along the time course, an increase in DCF fluorescence indicative of oxidative stress, depletion of superoxide dismutase (SOD) and glutathione reductase (GR) and consistent accumulation of 8-oxo-dG were noticed. Thus, endogenous oxidative stress resulted in aberrant expression of p53, p21, cyclin E and CDK2 proteins, suggestive of deregulated cell cycle, chromosomal aberrations, centromeric amplification, aneuploidy and genomic instability. 相似文献
9.
10.
S.A. Syam Kumar Raghavendra Holla Prabakar Sukumar Sriram Padmanaban Nagarajan Vivekanandan 《Reports of Practical Oncology and Radiotherapy》2013,18(2):87-94