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排序方式: 共有274条查询结果,搜索用时 15 毫秒
41.
Dariusz Stępiński Maria Kwiatkowska Agnieszka Wojtczak Eva Domínguez Antonio Heredia Katarzyna Popłońska 《Physiologia plantarum》2017,161(4):560-567
Cutinsomes, spherical nanoparticles containing cutin mono‐ and oligomers, are engaged in cuticle formation. Earlier they were revealed to participate in cuticle biosynthesis in Solanum lycopersicum fruit and Ornithogalum umbellatum ovary epidermis. Here, transmission electron microscopy (TEM) and immunogold labeling with antibody against the cutinsomes were applied to aerial cotyledon epidermal cells of Arabidopsis thaliana mature embryos. TEM as well as gold particles conjugated with the cutinsome antibody revealed these structures in the cytoplasm, near the plasmalemma, in the cell wall and incorporated into the cuticle. Thus, the cutinsomes most probably are involved in the formation of A. thaliana embryo cuticle and this model plant is another species in which these specific structures participate in the building of cuticle in spite of the lack of the lipotubuloid metabolon. In addition, a mechanism of plant cuticle lipid biosynthesis based on current knowledge is proposed. 相似文献
42.
Phosphorylation of H2AX histone results not only from DNA damage (caused by ionizing radiation, UV or chemical substances, e.g. hydroxyurea), but also regularly takes place during spermiogenesis, enabling correct chromatin remodeling. Immunocytochemical analysis using antibodies against H2AX histone phosphorylated at serine 139 indirectly revealed endogenous double-stranded DNA breaks in Chara vulgaris spermatids in mid-spermiogenesis (stages V, VI and VII), when protamine-type proteins appear in the nucleus. Fluorescent foci were not observed in early (stages I-IV) and late (VIII-X) spermiogenesis, after replacement of histones by protamine-type proteins was finished. A similar phenomenon exists in animals. Determination of the localization of fluorescent foci and the ultrastructure of nuclei led to the hypothesis that DNA breaks at stage V, when condensed chromatin adheres to the nuclear envelope. This is transformed into a net-like structure during stage VI, probably allowing chromosome repositioning to specific regions in the mature spermatozoid. However, at stages VI and VII, DNA breaks are necessary for transformation of the nucleosomal structure into a fibrillar and finally the extremely condensed status of sleeping genes at stage X. 相似文献
43.
Ben Langmead Michael C Schatz Jimmy Lin Mihai Pop Steven L Salzberg 《Genome biology》2009,10(11):R134-10
As DNA sequencing outpaces improvements in computer speed, there is a critical need to accelerate tasks like alignment and
SNP calling. Crossbow is a cloud-computing software tool that combines the aligner Bowtie and the SNP caller SOAPsnp. Executing
in parallel using Hadoop, Crossbow analyzes data comprising 38-fold coverage of the human genome in three hours using a 320-CPU
cluster rented from a cloud computing service for about $85. Crossbow is available from . 相似文献
44.
Ultrafast and memory-efficient alignment of short DNA sequences to the human genome 总被引:20,自引:0,他引:20
Bowtie is an ultrafast, memory-efficient alignment program for aligning short DNA sequence reads to large genomes. For the
human genome, Burrows-Wheeler indexing allows Bowtie to align more than 25 million reads per CPU hour with a memory footprint
of approximately 1.3 gigabytes. Bowtie extends previous Burrows-Wheeler techniques with a novel quality-aware backtracking
algorithm that permits mismatches. Multiple processor cores can be used simultaneously to achieve even greater alignment speeds.
Bowtie is open source . 相似文献
45.
Renata Krupa Anna Sobczuk Tomasz Popławski Katarzyna Wozniak Janusz Blasiak 《Molecular biology reports》2011,38(2):1163-1170
The cellular reaction to the DNA-damaging agents may modulate individual’s cancer susceptibility. This reaction is mainly
determined by the efficacy of DNA repair, which in turn, may be influenced by the variability of DNA repair genes, expressed
by their polymorphism. The hOGG1 gene encodes a glycosylase of base excision repair and RAD51 specifies a key protein in homologues recombination repair. Both proteins can be involved in the repair of DNA lesions, which
are known to contribute to endometrial cancer. In the present work we determined the extent of basal DNA damage and the efficacy
of removal of DNA damage induced by hydrogen peroxide and N-methyl-N′-nitro N-nitrosoguanidyne (MNNG) in peripheral blood
lymphocytes of 30 endometrial cancer patients and 30 individuals without cancer. The results from DNA damage and repair study
were correlated with the genotypes of two common polymorphisms of the hOGG1 and RAD51 genes: a G>C transversion at 1245 position of the hOGG1 gene producing a Ser → Cys substitution at the codon 326 (the Ser326Cys polymorphism) and a G>C substitution at 135 position
of the RAD51 gene (the 135G>C polymorphism). DNA damage and repair were evaluated by alkaline single cell gel electrophoresis and genotypes
were determined by restriction fragment length polymorphism PCR. We observed a strong association between endometrial cancer
and the C/C genotype of the 135G>C polymorphism of the RAD51 gene. Moreover, there was a strong correlation between that genotype and endometrial cancer occurrence in subjects with a
high level of basal DNA damage. We did not observe any correlation between the Ser326Cys polymorphism of the hOGG1 gene and endometrial cancer. Our result suggest that the 135G>C polymorphism of the RAD51 gene may be linked to endometrial cancer and can be considered as an additional marker of this disease. 相似文献
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48.
Pop Sevinci Enciu Ana Maria Tarcomnicu Isabela Gille Elvira Tanase Cristiana 《Phytochemistry Reviews》2019,18(4):1005-1024
Phytochemistry Reviews - Cancer can take many years to develop from initiation to progression. The long period of development might represent an opportunity to use multi-functional, multi-targeted... 相似文献
49.
50.
Norma L. Yoss Octavian Popescu Victor I. Pop Dorin Porutiu Fred A. Kummerow Gheorghe Benga 《Bioscience reports》1985,5(1):1-5
Methods for the complete characterization of liposomes prepared by ether-injection are described in detail. The validity of atomic absorption spectrophotometry Ior measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. The favorable results usingl atomic absorption spectrophotometry to quantitate the marker Mn2+ are of particular relevance as manganese ion is also the paramagnetic probe in n.m.r, measurements of water permeability of lipo-somes; our results indicate that in such measurements no other marker need be incorporated. 相似文献