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991.
Mutyala Satish M. Angel Nivya Suman Abhishek Naveen Kumar Nakarakanti Dixit Shivani Madishetti Vinuthna Vani Eerappa Rajakumara 《Proteins》2018,86(1):21-34
Histone lysine methylation by histone lysine methyltransferases (HKMTs) has been implicated in regulation of gene expression. While significant progress has been made to understand the roles and mechanisms of animal HKMT functions, only a few plant HKMTs are functionally characterized. To unravel histone substrate specificity, degree of methylation and catalytic activity, we analyzed Arabidopsis Trithorax‐like protein (ATX), Su (var)3‐9 h omologs protein (SUVH), Su(var)3‐9 related protein (SUVR), ATXR5, ATXR6, and E(Z) HKMTs of Arabidopsis, maize and rice through sequence and structure comparison. We show that ATXs may exhibit methyltransferase specificity toward histone 3 lysine 4 (H3K4) and might catalyse the trimethylation. Our analyses also indicate that most SUVH proteins of Arabidopsis may bind histone H3 lysine 9 (H3K9). We also predict that SUVH7, SUVH8, SUVR1, SUVR3, ZmSET20 and ZmSET22 catalyse monomethylation or dimethylation of H3K9. Except for SDG728, which may trimethylate H3K9, all SUVH paralogs in rice may catalyse monomethylation or dimethylation. ZmSET11, ZmSET31, SDG713, SDG715, and SDG726 proteins are predicted to be catalytically inactive because of an incomplete S‐adenosylmethionine (SAM) binding pocket and a post‐SET domain. E(Z) homologs can trimethylate H3K27 substrate, which is similar to the Enhancer of Zeste homolog 2 of humans. Our comparative sequence analyses reveal that ATXR5 and ATXR6 lack motifs/domains required for protein‐protein interaction and polycomb repressive complex 2 complex formation. We propose that subtle variations of key residues at substrate or SAM binding pocket, around the catalytic pocket, or presence of pre‐SET and post‐SET domains in HKMTs of the aforementioned plant species lead to variations in class‐specific HKMT functions and further determine their substrate specificity, the degree of methylation and catalytic activity. 相似文献
992.
Because of its wide geographical adaptation and importance in human nutrition, wheat is one of the most important crops in the world. However, wheat yield has reduced due to drought stress posing threat to sustainability and world food security in agricultural production. The first stage of drought tolerant variety breeding occurs on the molecular and biochemical characterization and classification of wheat genotypes. The aim of the present study is characterization of widely grown bread wheat cultivars and breeding lines for drought tolerance so as to be adapted to different regions in Turkey. The genotypes were screened with molecular markers for the presence of QTLs mapped to different chromosomes. Results of the molecular studies identified and detected 15 polymorphic SSR markers which gave the clearest PCR bands among the control genotypes. At the end of the research, bread wheat genotypes which were classified for tolerance or sensitivity to drought and the genetic similarity within control varieties were determined by molecular markers. According to SSR based dendrogram, two main groups were obtained for drought tolerance. At end of the molecular screening with SSR primers, genetic similarity coefficients were obtained that ranged from 0.14 to 0.71. The ones numbered 8 and 11 were the closest genotypes to drought tolerant cultivar Gerek 79 and the furthest genotypes from this cultivar were number 16 and to drought sensitive cultivar Sultan 95. The genotypes as drought tolerance due to their SSR markers scores are expected to provide useful information for drought related molecular breeding studies. 相似文献
993.
This study aimed to investigate the effects of arsenic trioxide (As2O3) on the mitochondrial DNA (mtDNA) of acute promyelocytic leukemia (APL) cells. The NB4 cell line was treated with 2.0 μmol/L
As2O3
in vitro, and the primary APL cells were treated with 2.0 μmol/L As2O3
in vitro and 0.16 mg kg−1 d−1 As2O3
in vivo. The mitochondrial DNA of all the cells above was amplified by PCR, directly sequenced and analyzed by Sequence Navigatore
and Factura software. The apoptosis rates were assayed by flow cytometry. Mitochondrial DNA mutation in the D-loop region was found in NB4 and APL cells before As2O3 use, but the mutation spots were remarkably increased after As2O3 treatment, which was positively correlated to the rates of cellular apoptosis, the correlation coefficient: r
NB4-As2O3=0.973818, and r
APL-As2O3=0.934703. The mutation types include transition, transversion, codon insertion or deletion, and the mutation spots in all
samples were not constant and regular. It is revealed that As2O3 aggravates mtDNA mutation in the D-loop region of acute promyelocytic leukemia cells both in vitro and in vivo. Mitochondrial DNA might be one of the targets of As2O3 in APL treatment. 相似文献
994.
Ismail Eş Maycon Carvalho Ribeiro Samuel Rodrigues dos Santos Júnior Amin Mousavi Khaneghah Armando Garcia Rodriguez André Corrêa Amaral 《Bioprocess and biosystems engineering》2016,39(10):1487-1500
The whole-cell immobilization on chitosan matrix was evaluated. Bacillus sp., as producer of CGTase, was grown in solid-state and batch cultivation using three types of starches (cassava, potato and cornstarch). Biomass growth and substrate consumption were assessed by flow cytometry and modified phenol–sulfuric acid assays, respectively. Qualitative analysis of CGTase production was determined by colorless area formation on solid culture containing phenolphthalein. Scanning electron microscopy (SEM) analysis demonstrated that bacterial cells were immobilized on chitosan matrix efficiently. Free cells reached very high numbers during batch culture while immobilized cells maintained initial inoculum concentration. The maximum enzyme activity achieved by free cells was 58.15 U ml?1 (36 h), 47.50 U ml?1 (36 h) and 68.36 U ml?1 (36 h) on cassava, potato and cornstarch, respectively. CGTase activities for immobilized cells were 82.15 U ml?1 (18 h) on cassava, 79.17 U ml?1 (12 h) on potato and 55.37 U ml?1 (in 6 h and max 77.75 U ml?1 in 36 h) on cornstarch. Application of immobilization technique increased CGTase activity significantly. The immobilized cells produced CGTase with higher activity in a shorter fermentation time comparing to free cells. 相似文献
995.
Zhenhua Gao Lingxiao Wang Fu Wang Chunmei Zhang Jinsong Wang Junqi He Songlin Wang 《Journal of molecular histology》2018,49(5):545-553
Bone morphogenetic proteins (BMPs) play important roles in tooth development. However, their expression has not been studied in miniature pigs, which have many anatomical similarities in oral and maxillofacial region compared to human. This study investigated BMP2/4/7 expression patterns during deciduous molar development in miniature pigs on embryonic days (E) 40, 50, and 60. The mandibles were fixed, decalcified, and embedded before sectioning. H&E staining, immunohistochemistry, in situ hybridization using specific radionuclide-labeled cRNA probes, and real-time PCR were used to detect the BMP expression patterns during morphogenesis of the third deciduous molar. H&E staining showed that for the deciduous third molar, E40 represented the cap stage, E50 represented the early bell stage, and E60 represented the late bell stage or secretory stage. BMP2 was expressed in both the enamel organ and in the dental mesenchyme on E40 and E50 and was expressed mainly in pre-odontoblasts on E60. BMP7 expression was similar to BMP2 expression, but BMP7 was also expressed in the inner enamel epithelium on E60. On E40, BMP4 was expressed mainly in the epithelium, with some weak expression in the mesenchyme. On E50, BMP4 expression was stronger in the mesenchyme but weaker in the epithelium. On E60, BMP4 was expressed mainly in the mesenchyme. These data indicated that BMP2/4/7 showed differential spatial and temporal expression during the morphogenesis and odontogenesis of deciduous molars, suggesting that these molecules were associated with tooth morphogenesis and cell differentiation. 相似文献
996.
Frank R. Thomas 《Human ecology: an interdisciplinary journal》2007,35(2):179-194
Focusing on contemporary shellfish exploitation among several atoll communities in Kiribati, Micronesia, this paper examines
the relationship between human foragers and their invertebrate prey via the prey choice or diet breadth model derived from
optimal foraging theory. Shellfish, like many other reef organisms, are relatively sedentary and predictable, but these characteristics
make them susceptible to over-harvesting. The research reveals that shellfish gatherers are foraging in a manner that matches
the predictions of optimal foraging theory. The work adds to our understanding of optimal foraging decisions in atoll settings
by critically evaluating the depiction of atoll dwellers as conservationists.
相似文献
Frank R. ThomasEmail: Email: |
997.
The effect of water deficit on chlorophyll fluorescence, sugar content, and growth parameters of strawberry (Fragaria×ananassa Duch. cv. Elsanta) was studied. Drought stress caused significant reductions in leaf water potential, fresh and dry masses,
leaf area, and leaf number. A gradual reduction of photochemical quenching (qP) and quantum efficiency (ΦPS2) was observed under drought stress while non-photochemical quenching (qN) increased. Maximum efficiency of photosystem 2 (Fv/Fm) was not affected by drought stress. 相似文献
998.
Gaelle Rossignol Annabelle Merieau Josette Guerillon Wilfried Veron Olivier Lesouhaitier Marc GJ Feuilloley Nicole Orange 《BMC microbiology》2008,8(1):189
Background
Pseudomonas fluorescens is a ubiquitous Gram-negative bacterium frequently encountered in hospitals as a contaminant of injectable material and surfaces. This psychrotrophic bacterium, commonly described as unable to grow at temperatures above 32°C, is now considered non pathogenic. We studied a recently identified clinical strain of P. fluorescens biovar I, MFN1032, which is considered to cause human lung infection and can grow at 37°C in laboratory conditions. 相似文献999.
Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts
of type I interferons (IFNs) in response to viral infection. The function of pDCs as the professional type I IFN-producing
cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9, which sense viral nucleic acids within
the endosomal compartments. Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential
role in linking the innate and adaptive immune system. The aberrant activation of pDCs by self nucleic acids through TLR signaling
and the ongoing production of type I IFNs do occur in some autoimmune diseases. Therefore, pDC may serve as an attractive
target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases. 相似文献
1000.
MicroRNA-190b confers radio-sensitivity through negative regulation of Bcl-2 in gastric cancer cells