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排序方式: 共有254条查询结果,搜索用时 15 毫秒
81.
Haroon Urooj Khizar Maria Liaquat Fiza Ali Musrat Akbar Mahnoor Tahir Kinza Batool Syeda Saira Kamal Asif Chaudhary Hassan Javed Munis Muhammad Farooq Hussain 《Journal of Plant Growth Regulation》2022,41(6):2435-2448
Journal of Plant Growth Regulation - Soil salinity is one of the main yield-limiting factors in various crops. Under different environmental stresses, many rhizobacteria have demonstrated... 相似文献
82.
Javed Maryam Nadeem Asif Hassan Faiz-ul Mujahid Huma Rehman Saif ur 《Molecular biology reports》2022,49(10):9315-9324
Molecular Biology Reports - Poor estrus expression behavior causes suboptimal reproductive efficiency through poor conception rate. Various signaling pathways are involved in estrus expression but... 相似文献
83.
Mina Darooei Fazal Khan Mohd Rehan Syeda Zubeda Erukambattu Jeyashanker Srirambhatla Annapurna Ashwin Shah Srinivas Maddali Qurratulain Hasan 《Journal of cellular biochemistry》2019,120(1):182-191
Fibroadenoma is the most common type of benign breast tumor, accounting for 90% of benign lesions in India. Somatic mutations in the mediator complex subunit 12 (MED12) gene play a critical role in fibroepithelial tumorigenesis. The current study evaluated the hotspot region encompassing exon 2 of the MED12 gene, in benign and malignant breast tumor tissue from women who presented for breast lump evaluation. A total of 100 (80 fibroadenoma and 20 breast cancer) samples were analyzed by polymerase chain reaction-Sanger sequencing. Sequence variant analysis showed that 68.75% of nucleotide changes were found in exon 2 and the remaining in the adjacent intron 1. Codon 44 was implicated as a hotspot mutation in benign tumors, and 86.36% of the identified mutations involved this codon. An in silico functional analysis of missense mutations using consensus scoring sorting intolerant from tolerant (SIFT), SIFT seq, Polyphen2, Mutation Assessor, SIFT transFIC, Polyphen2 transFIC, Mutation Assesor transFIC, I-Mutant, DUET, PON-PS, SNAP2, and protein variation effect analyzer] revealed that apart from variants involving codon 44 (G44S; G44H), others like V41A and E55D were also predicted to be deleterious. Most of the missense mutations appeared in the loop region of the MED12 protein, which is expected to affect its functional interaction with cyclin C–CDK8/CDK19, causing loss of mediator-associated cyclin depended kinase (CDK) activity. These results suggest a key role of MED12 somatic variations in the pathogenesis of fibroadenoma. For the first time, it was demonstrated that MED12 sequence variations are present in benign breast tumors in the south Indian population. 相似文献
84.
Hiroyuki Hiraishi Jamie Oatman Sherry L. Haller Logan Blunk Benton McGivern Jacob Morris Evangelos Papadopoulos Wade Gutierrez Michelle Gordon Wahaj Bokhari Yuka Ikeda David Miles John Fellers Masayo Asano Gerhard Wagner Loubna Tazi Stefan Rothenburg Susan J. Brown Katsura Asano 《Nucleic acids research》2014,42(16):10321-10330
85.
Jiagui Qu Joshua D. Rizak Yaodong Fan Xiaoxuan Guo Jiejing Li Tanzeel Huma Yuanye Ma 《Human cell》2014,27(3):129-136
This paper outlines the establishment of a new and stable cell line, designated GBM-HSF, from a malignant glioblastoma multiforme (GBM) removed from a 65-year-old Chinese woman. This cell line has been grown for 1 year without disruption and has been passaged over 50 times. The cells were adherently cultured in RPMI-1640 media with 10 % fetal bovine serum supplementation. Cells displayed spindle and polygonal morphology, and displayed multi-layered growth without evidence of contact inhibition. The cell line had a high growth rate with a doubling time of 51 h. The cells were able to grow without adhering to the culture plates, and 4.5 % of the total cells formed colonies in soft agar. The cell line has also been found to form tumors in nude mice and to be of a highly invasive nature. The cells were also partially characterized with RT-PCR. The RT-PCR revealed that Nestin, β-tubulin III, Map2, Klf4, Oct4, Sox2, Nanog, and CD26 were positively transcribed, whereas GFAP, Rex1, and CD133 were negatively transcribed in this cell line. These results suggest that the GBM-HSF cell line will provide a good model to study the properties of cancer stem cells and metastasis. It will also facilitate more detailed molecular and cellular studies of GBM cell division and pathology. 相似文献
86.
Aisha H. Syeda Michelle Hawkins Peter McGlynn 《Cold Spring Harbor perspectives in biology》2014,6(11)
The links between recombination and replication have been appreciated for decades and it is now generally accepted that these two fundamental aspects of DNA metabolism are inseparable: Homologous recombination is essential for completion of DNA replication and vice versa. This review focuses on the roles that recombination enzymes play in underpinning genome duplication, aiding replication fork movement in the face of the many replisome barriers that challenge genome stability. These links have many conserved features across all domains of life, reflecting the conserved nature of the substrate for these reactions, DNA.The interplay between replication and recombination is complex in terms of both mechanism and integration within DNA metabolism. At the heart of this interplay is the requirement for single-stranded DNA (ssDNA), the substrate for DNA-strand-exchange proteins, to initiate recombination (Cox 2007b; San Filippo et al. 2008). Whether, when, and where this ssDNA is generated determines the functional relationship between replication and recombination, a relationship that can operate in both directions. Homologous recombination enzymes are critical for successful completion of genome duplication (Kogoma 1997; Cox et al. 2000) but DNA replication also underpins homologous recombination, as discussed elsewhere in this collection. The links between recombination and replication are therefore intimate and one cannot be considered in isolation from the other. However, involvement of DNA-strand-exchange proteins, regardless of the metabolic context, comes with the unavoidable risk of genome rearrangements. This genome instability can occasionally increase evolutionary fitness but more frequently is deleterious to the viability of the individual.This review will focus on fundamental aspects of the links between replication and recombination enzymes rather than simply providing a list of known enzymes and reactions. The substrate, DNA, is identical in all of these reactions and this is reflected in the high mechanistic conservation of replication and recombination. 相似文献
87.
Yonus H Neumann P Zimmermann S May JJ Marahiel MA Stubbs MT 《The Journal of biological chemistry》2008,283(47):32484-32491
DltA, the D-alanine:D-alanyl carrier protein ligase responsible for the initial step of lipoteichoic acid D-alanylation in Gram-positive bacteria, belongs to the adenylation domain superfamily, which also includes acetyl-CoA synthetase and the adenylation domains of non-ribosomal synthetases. The two-step reaction catalyzed by these enzymes (substrate adenylation followed by transfer to the reactive thiol group of CoA or the phosphopantheinyl prosthetic group of peptidyl carrier proteins) has been suggested to proceed via large scale rearrangements of structural domains within the enzyme. The structures of DltA reported here reveal the determinants for D-Ala substrate specificity and confirm that the peptidyl carrier protein-activating domains are able to adopt multiple conformational states, in this case corresponding to the thiolation reaction. Comparisons of available structures allow us to propose a mechanism whereby small perturbations of finely balanced metastable structural states would be able to direct an ordered formation of non-ribosomal synthetase products. 相似文献
88.
89.
Australia's prospects to become a key energy exporter in the Asia‐Pacific region has driven rapid development and expansion of its coal seam gas (CSG) industry, particularly in regional Queensland, Australia. The vast majority of Australia's current CSG developments and reserves are situated in agriculture‐rich, cattle‐grazing regions; therefore, it is critical to identify symbiotic relationships between agri‐based industries and the CSG industry to achieve beneficial coexistence. The CSG industry has generated infrastructure such as gas and water pipelines, water storage and treatment facilities, transportation and electricity networks, and other CSG‐associated services (e.g., accommodation, education, and medical facilities), which have the potential to improve regional communities and facilitate economic growth. This article aims to investigate these coexistence opportunities, including the use of by‐products (mainly water produced during CSG extraction), infrastructure, and services generated from the CSG industry, which can provide value to the local industries. Focusing on the cattle value chain, the authors suggest an agri‐based industrial coexistence model that indicates material‐water flows and optimized utilization of infrastructure that not only promote coexistence between the agribusiness and CSG industries, but expand the cattle value‐chain productivity in rural Queensland. A water balance has been conducted around the suggested coexistence model with the aim of quantifying water flows, to indicate the supply versus demand scenario associated with CSG‐sourced water production. The results of the water balance indicate that CSG water supply has the potential to meet the requirements of agribusiness promoting industries. 相似文献
90.
Syeda Shahnaz Parvez Mohammad Masud Parvez Yoshiharu Fujii Hiroshi Gemma 《Plant Growth Regulation》2004,42(3):245-252
Allelopathic performance of the bark and seed of Tamarindus indica L. tree was evaluated through bioassay-guided studies using seven common agronomic crops (asparagus, cucumber, lettuce, radish,
sesame, tomato and welsh onion) and seven weed species (barnyard grass, Chinese milk vetch, perennial ryegrass, phacelia,
timothy grass, white clover and wild ginger) under laboratory conditions. As demonstrated by a sandwich method, the bark of
the tamarind tree caused strong growth inhibition (compared to the corresponding controls) in both radicles and hypocotyls
of the species tested, and the inhibitory effect was highest in barnyard grass (52–65%) and lowest in welsh onion (19–13%).
The crude-water soluble extracts of bark at different concentrations (1, 5 and 10%) (w/v) exhibited a strong growth inhibition
in all the plant species tested, and a proportional increase in the percentage of growth inhibition was observed with an increase
in the concentrations of the extracts. The magnitude of inhibition in weed species was higher (5–60%) than those of agronomic
crop species (3–40%). The growth of all the weed species tested was strongly inhibited (17–56%), while the agronomic crop
species showed both inhibited (5–21%) and stimulated (5–27%) growth due to the effect of crude-water soluble exudates of tamarind
seed. Among the agronomic crop species tested, lettuce (22–27%) followed by radish (20–25%) and sesame (5–8%) showed stimulatory
growth with the crude-water soluble exudates of seed. In the pot culture experiments using four agronomic crops (lettuce,
radish, tomato and cucumber) and two weed species (barnyard grass and white clover), spraying of crude-water soluble extracts
of tamarind seed-coat at three different concentrations (1, 5 and 10%) (w/v) showed that the growth of lettuce (35–62%) and
radish (32–56%) was stimulated, while all other species tested showed growth inhibition (29–61%). When the spraying of crude
extracts of seed-coat was turned off, the growth of both lettuce and radish continued to be stimulated (4–7%) and all other
previously inhibited species recovered well, the recovery percentage ranging between 78 and 82%. However, when spraying of
crude extracts of seed-coat was continued, growth increased (10–14%) in lettuce and radish, and reduced (37–76%) in four other
species tested. The inhibitory or stimulatory effects of the crude extracts on agronomic crop and weed species were higher
in the radicle than the hypocotyl and reached a peak with 10% (w/v) concentrations. These results clearly demonstrated the
differential allelopathic effects (inhibitory and excitatory) of bark and seed of tamarind tree in the species tested. Thus,
it is evident that these two organs contain certain biologically active true growth regulator(s) and are either additively
or synergistically involved in the plant-specific expression, particularly by the seed-coat. 相似文献