1,721,041 research outputs found
Profiling Transposable Elements and Their Epigenetic Effects in Non-model Species
No full textTaking transposable elements into consideration in surveys of genetic and epigenetic variation remains challenging in species lacking a high-quality reference genome. Here, molecular techniques reducing genome complexity and specifically targeting restructuring and methylation changes in TE genome fractions are described. In particular, methyl-sensitive transposon display (MSTD) uses isoschizomers and PCR amplifications to assess the methylation environment of TE insertions. MSTD offers reliable insights into genome-wide epigenetic changes associated with TEs, especially when used together with similar techniques tracking random sequences
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
The versatile role of homologous recombination in plant cell : repair of DNA damage, stress-directed genome evolution and foreign DNA integration
Get PDFxxi, 246 leaves : ill. ; 29 cm. --Homologous recombination represents a DNA repair pathway. Its role in a plant cell is not limited to double strand break repair. It also extends to genome evolution via rearranging of DNA sequences, and has an important application in foreign DNA integration in the plant genome. Our study demonstrated that effects exerted by stress on homologous recombination and genome stability are not restricted to the exposed generation. The progeny of plants exposed to stress exhibited elevated spontaneous homologous recombination, changes in DNA methylation and higher tolerance to stress. These heritable changes are mediated by an unknown stress-inducible epigenetic signal. Furthermore, we demonstrated that using factors that enhance homologous recombination can improve the efficiency of genetic transformation by Agrobacterium. We have developed and patented a plant growth medium enhancing homologous recombination and significantly increasing the transformation frequency. The role of several other chemicals for the improvement of transformation was also evaluated
Transgenic assays for the analysis of DNA repair in plants
Get PDFxi, 132 leaves : ill. ; 29 cm.In this work we studied various aspects of DNA repair in plants, focusing mainly on point mutation repair and its interconnection with double-strand break repair. We were using transgenic point mutation and recombination substrates as a primary tool in our experiments. We have compared two transgenic homologous recombination assays (B-glucuronidase- and luciferase-based), analyzed the sensitivity of DNA repair machinery to ultraviolet radiation and assessed the involvement of AtKu80, Atm and AtXpd repair genes in point mutation repair. Ours study revealed the following: the luciferase-based recombination assay is more sensitive then B-glucuronidase-based; double-stand break repair machinery is sensitive to ultraviolet radiation, which results in increased pint mutation formation; chosen DNA repair genes might be impaired in point mutation repair, however further experimentations are needed to confirm this
Transgenerational changes in progeny of compatible pathogen infected plants
Get PDFxi, 176 leaves : ill. (chiefly col.) ; 29 cm[No abstract available
The effect of pathogens on plant genome stability
Get PDFxiii, 119 leaves ; 29 cm.Resistance (R) genes, a key factor in determining the resistance of plants, have been shown often to be highly allelic entities existing in duplicated regions of the genome. This characteristic suggests that R-gene acquisition may have arisen through frequent genetic rearrangements as a result of transient, reduced genome stability. Tabacco plants transgenic for a recombination construct exhibited reduced genome stability upon infection with a virulent pathogen (tobacco mosaic virus). The reduced genome stability manifested as an increase in recombination events in the transgene. Such increases were observed following a virulent pathogen attack. This increase in recombination was shown to be systemic and was observed prior to systemic viral movement suggesting the presence of a systemic recombination signal. Further molecular analyses revealed that specific R-gene loci experience a large frequency of rearrangements following a virulent pathogen encounter. The possible targeting of instability to R-gene regions may be controlled through epigenetic processes, in particular, DNA methylation
Cannabinol inhibits proliferation and induces cell cycle arrest and apoptosis in glioblastoma, hepatocellular carcinoma and breast cancer cells
Get PDFCannabis sativa is an agriculturally and medicinally important plant with many pharmaceutical properties. Cancer is a deadly disease; it is estimated that it will cause over 80 thousand deaths in 2019 in Canada. Although numerous studies have demonstrated that cannabinoids have anti-tumorous properties in various cancers, the anti-malignant activities of cannabinol (CBN) on carcinogenesis and underlying mechanisms remain largely unknown. In this study, we provide evidence that CBN inhibits proliferation of A172, HB8065 and HCC1806 cells in a dose- and time-dependent manner. CBN regulates expression of cannabinoid receptors, CB2, GPR55 and GPR18 in different cell lines, while reducing levels of phosphorylated ERK1/2 in HCC1806 and phosphorylated AKT in A172 and HB8065 cells. We find that CBN induces apoptosis through downregulation of p21 and p27 and a G1 or S-phase cell cycle arrest through a dose-dependent downregulation of cyclin E1, CDK1 and CDK2. These data support the medicinal potential of CBN in anti-cancer therapy.Mitac
Genomic and epigenomic changes in transgenerational response to cold stress in Arabidopsis thaliana
Get PDFPlants are continuously exposed to various environmental stresses. They employ numerous strategies of resistance and develop a memory of stress exposure for future generations. Abiotic stress, like cold, can prompt the changes in phenotype, genotype, and epigenotype of plants. Plants can establish these as somatic and transgenerational memories. We studied the Arabidopsis thaliana plants exposed to multiple generations of cold stress. We hypothesized that the progeny of plants exposed to 25 generations to cold stress would be genetically and epigenetically more diverse than the parental plants. Our study reveals that multigenerational exposure to cold stress resulted in the physiological changes, as well as changes in the genomic and epigenomic (DNA methylation) patterns across generations. The main changes in the progeny were due to the high frequency of genetic mutations rather than epigenetic changes. Our work supports the existence of transgenerational stress response in plants and demonstrates that genetic changes prevail
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