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351.
Plant productivity is greatly influenced by various environmental stresses, such as high salinity and drought. Earlier, we
reported the isolation of topoisomerase 6 homologs from rice and showed that over expression of OsTOP6A3 and OsTOP6B confers abiotic stress tolerance in transgenic Arabidopsis plants. In this study, we have assessed the function of nuclear-localized topoisomerase 6 subunit A homolog, OsTOP6A1, in
transgenic Arabidopsis plants. The over expression of OsTOP6A1 in transgenic Arabidopsis plants driven by cauliflower mosaic virus-35S promoter resulted in pleiotropic effects on plant growth and development. The
transgenic Arabidopsis plants showed reduced sensitivity to stress hormone, abscisic acid (ABA), and tolerance to high salinity and dehydration
at the seed germination; seedling and adult stages as reflected by the percentage of germination, fresh weight of seedlings
and leaf senescence assay, respectively. Concomitantly, the expression of many stress-responsive genes was enhanced under
various stress conditions in transgenic Arabidopsis plants. Moreover, microarray analysis revealed that the expression of a large number of genes involved in various processes
of plant growth and development and stress responses was altered in transgenic plants. Although AtSPO11-1, the homolog of
OsTOP6A1 in Arabidopsis, has been implicated in meiotic recombination; the present study demonstrates possible additional role of OsTOP6A1 and provides
an effective tool for engineering crop plants for tolerance to different environmental stresses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
352.
The malleable brain: plasticity of neural circuits and behavior – a review from students to students
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![点击此处可从《Journal of neurochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Natascha Schaefer Carola Rotermund Eva‐Maria Blumrich Mychael V. Lourenco Pooja Joshi Regina U. Hegemann Sumit Jamwal Nilufar Ali Ezra Michelet García Romero Sorabh Sharma Shampa Ghosh Jitendra K. Sinha Hannah Loke Vishal Jain Katarzyna Lepeta Ahmad Salamian Mahima Sharma Mojtaba Golpich Katarzyna Nawrotek Ramesh K. Paidi Sheila M. Shahidzadeh Tetsade Piermartiri Elham Amini Veronica Pastor Yvette Wilson Philip A. Adeniyi Ashok K. Datusalia Benham Vafadari Vedangana Saini Edna Suárez‐Pozos Neetu Kushwah Paula Fontanet Anthony J. Turner 《Journal of neurochemistry》2017,142(6):790-811
353.
Lalit?Kumar?Gautam Mohit?Yadav Jitendra?Singh?RathoreEmail author 《Journal of molecular modeling》2017,23(6):189
Toxin–antitoxin (TA) complexes play an important role in stress responses and programmed cell death in bacteria. The RelB-RelE toxin antitoxin system is well studied in Escherichia coli. In this study, we used combined in silico and in vitro approaches to study a novel Xn-RelT toxin from Xenorhabdus nematophila bearing its own antitoxin Xn-RelAT—a RelB homolog of E. coli. The structure for this toxin–antitoxin pair is yet unknown. We generated homology-based models of X. nematophila RelT toxin and antitoxin. The deduced models were further characterized for protein–nucleic acid, protein–protein interactions and gene ontology. A detrimental effect of recombinant Xn-RelT on host E. coli was determined through endogenous toxicity assay. When expressed from a isopropyl β-d-1-thiogalactopyranoside-regulated LacZ promoter, Xn-RelT toxin showed a toxic effect on E. coli cells. These observations imply that the conditional cooperativity governing the Xn-RelT TA operon in X. nematophila plays an important role in stress management and programmed cell death. 相似文献
354.
Matsuyama M Shiraishi T Sundaray JK Rahman A Ohta K Yamaguchi A 《Zoological science》2005,22(1):101-110
We incubated different radiolabeled steroid precursors with intact chub mackerel ovarian follicles to clarify the synthetic pathways of steroid hormones during vitellogenesis and following final oocyte maturation (FOM). During vitellogenesis, estradiol-17beta (E2) was synthesized from pregnenolone via 17-hydroxypregnenolone, 17-hydroxyprogesterone, androstenedione, and testosterone. The physiological significance of the intermediate metabolites of E2 in the ovarian follicles was examined by comparing follicular steroidogenesis between gonochoric and hermaphroditic fish species. After vitellogenesis, the steroidogenic pathway shifted from E2 to maturation-inducing hormone (MIH) production owing to the inactivation of 17,20-lyase and the activation of 20 beta-hydroxysteroid dehydrogenase. Of the new steroids produced during FOM, 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P) was most effective at inducing germinal vesicle breakdown in vitro. Circulating levels of 17,20beta-P increased specifically around the time of germinal vesicle migration, while another FOM-specific 20beta-hydroxylated progestin, 17,20beta,21-trihydroxy-4-pregnen-3-one, was present at consistently low levels during FOM. These results indicate that 17,20beta-P is the MIH of chub mackerel. 相似文献
355.
356.
Electric field-driven transformations of a supported model biological membrane--an electrochemical and neutron reflectivity study
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![点击此处可从《Biophysical journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Burgess I Li M Horswell SL Szymanski G Lipkowski J Majewski J Satija S 《Biophysical journal》2004,86(3):1763-1776
A mixed bilayer of cholesterol and dimyristoylphosphatidylcholine has been formed on a gold-coated block of quartz by fusion of small unilamellar vesicles. The formation of this bilayer lipid membrane on a conductive surface allowed us to study the influence of the support's surface charge on the structure and hydration of the bilayer lipid membrane. We have employed electrochemical measurements and the specular reflection of neutrons to measure the thickness and water content in the bilayer lipid membrane as a function of the charge on the support's surface. When the surface charge density is close to zero, the lipid vesicles fuse directly on the surface to form a bilayer with a small number of defects and hence small water content. When the support's surface is negatively charged the film swells and incorporates water. When the charge density is more negative than −8 μC cm−2, the bilayer starts to detach from the metal surface. However, it remains in a close proximity to the metal electrode, being suspended on a thin cushion of the electrolyte. The field-driven transformations of the bilayer lead to significant changes in the film thicknesses. At charge densities more negative than −20 μC cm−2, the bilayer is ~37 Å thick and this number is comparable to the thickness determined for hydrated multilayers of dimyristoylphosphatidylcholine from x-ray diffraction experiments. The thickness of the bilayer decreases at smaller charge densities to become equal to ~26 Å at zero charge. This result indicates that the tilt of the acyl chains with respect to the bilayer normal changes from ~35° to 59° by moving from high negative charges (and potentials) to zero charge on the metal. 相似文献
357.
358.
Tyagi AK Khurana JP Khurana P Raghuvanshi S Gaur A Kapur A Gupta V Kumar D Ravi V Vij S Khurana P Sharma S 《Journal of genetics》2004,83(1):79-99
Rice is an excellent system for plant genomics as it represents a modest size genome of 430 Mb. It feeds more than half the
population of the world. Draft sequences of the rice genome, derived by whole-genome shotgun approach at relatively low coverage
(4-6 X), were published and the International Rice Genome Sequencing Project (IRGSP) declared high quality (> 10 X), genetically
anchored, phase 2 level sequence in 2002. In addition, phase 3 level finished sequence of chromosomes 1, 4 and 10 (out of
12 chromosomes of rice) has already been reported by scientists from IRGSP consortium. Various estimates of genes in rice
place the number at >50,000. Already, over 28,000 full-length cDNAs have been sequenced, most of which map to genetically
anchored genome sequence. Such information is very useful in revealing novel features of macroand micro-level synteny of rice
genome with other cereals. Microarray analysis is unraveling the identity of rice genes expressing in temporal and spatial
manner and should help target candidate genes useful for improving traits of agronomic importance. Simultaneously, functional
analysis of rice genome has been initiated by marker-based characterization of useful genes and employing functional knock-outs
created by mutation or gene tagging. Integration of this enormous information is expected to catalyze tremendous activity
on basic and applied aspects of rice genomics. 相似文献
359.
Singh NK Raghuvanshi S Srivastava SK Gaur A Pal AK Dalal V Singh A Ghazi IA Bhargav A Yadav M Dixit A Batra K Gaikwad K Sharma TR Mohanty A Bharti AK Kapur A Gupta V Kumar D Vij S Vydianathan R Khurana P Sharma S McCombie WR Messing J Wing R Sasaki T Khurana P Mohapatra T Khurana JP Tyagi AK 《Functional & integrative genomics》2004,4(2):102-117
The DNA sequence of 106 BAC/PAC clones in the minimum tiling path (MTP) of the long arm of rice chromosome 11, between map positions 57.3 and 116.2 cM, has been assembled to phase 2 or PLN level. This region has been sequenced to 10× redundancy by the Indian Initiative for Rice Genome Sequencing (IIRGS) and is now publicly available in GenBank. The region, excluding overlaps, has been predicted to contain 2,932 genes using different software. A gene-by-gene BLASTN search of the NCBI wheat EST database of over 420,000 cDNA sequences revealed that 1,143 of the predicted rice genes (38.9%) have significant homology to wheat ESTs (bit score 100). Further BLASTN search of these 1,143 rice genes with the GrainGenes database of sequence contigs containing bin-mapped wheat ESTs allowed 113 of the genes to be placed in bins located on wheat chromosomes of different homoeologous groups. The largest number of genes, about one-third, mapped to the homoeologous group 4 chromosomes of wheat, suggesting a common evolutionary origin. The remaining genes were located on wheat chromosomes of different groups with significantly higher numbers for groups 3 and 5. Location of bin-mapped wheat contigs to chromosomes of all the seven homoeologous groups can be ascribed to movement of genes (transpositions) or chromosome segments (translocations) within rice or the hexaploid wheat genomes. Alternatively, it could be due to ancient duplications in the common ancestral genome of wheat and rice followed by selective elimination of genes in the wheat and rice genomes. While there exists definite conservation of gene sequences and the ancestral chromosomal identity between rice and wheat, there is no obvious conservation of the gene order at this level of resolution. Lack of extensive colinearity between rice and wheat genomes suggests that there have been many insertions, deletions, duplications and translocations that make the synteny comparisons much more complicated than earlier thought. However, enhanced resolution of comparative sequence analysis may reveal smaller conserved regions of colinearity, which will facilitate selection of markers for saturation mapping and sequencing of the gene-rich regions of the wheat genome. 相似文献
360.