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11.
Peramaiyan Rajendran Abdullah M Alzahrani Hamza N Hanieh Sekar Ashok Kumar Rebai Ben Ammar Thamaraiselavan Rengarajan Mohammed A Alhoot 《Journal of cellular physiology》2019,234(12):21485-21492
Senescence and autophagy play important roles in homeostasis. Cellular senescence and autophagy commonly cause several degenerative processes, including oxidative stress, DNA damage, telomere shortening, and oncogenic stress; hence, both events are known to be interrelated. Autophagy is well known for its disruptive effect on human diseases, and it is currently proposed to have a direct effect on triggering senescence and quiescence. However, it is yet to be proven whether autophagy has a positive or negative impact on senescence. It is known that elevated levels of autophagy induce cell death, whereas inadequate autophagy can trigger cellular senescence. Both have important roles in human diseases such as aging, renal degeneration, neurodegenerative disorders, and cancer. Therefore, this review aims to highlight the relevance of senescence and autophagy in selected human ailments through a summary of recent findings on the connection and effects of autophagy and senescence in these diseases. 相似文献
12.
Medicinal herbs used in indigenous medicines for the management of diabetes mellitus contain both organic and inorganic constituents.
Some of these inorganic trace elements possess antidiabetic properties, which accounts for the activity of medicinal herbs.
The aim of this study was to analyze the inorganic trace elements present in Eugenia jambolana seeds and to evaluate the hypoglycemic activity of the inorganic part of E. jambolana seeds on streptozotocin-induced diabetes. The seeds of E. jambolana seeds were reduced to ash and the inorganic elements present were assayed. The hypoglycemic efficacy of the inorganic part
was tested by the glucose tolerance test on streptozotocin-induced diabetes. Elements such as zinc, chromium, vanadium, potassium,
and sodium, possessing hypoglycemic activity, were present in the seed. The E. jambolana seed ashtreated diabetic rats exhibited normoglycemia and better glucose tolerance. The conclusion that the inorganic constituents
might play a important role in the antidiabetic nature E. jambolana seeds was reached. 相似文献
13.
Conformation Angles DataBase (CADB) provides an online resource to access data on conformation angles (both main-chain and side-chain) of protein structures in two data sets corresponding to 25% and 90% sequence identity between any two proteins, available in the Protein Data Bank. In addition, the database contains the necessary crystallographic parameters. The package has several flexible options and display facilities to visualize the main-chain and side-chain conformation angles for a particular amino acid residue. The package can also be used to study the interrelationship between the main-chain and side-chain conformation angles. A web based JAVA graphics interface has been deployed to display the user interested information on the client machine. The database is being updated at regular intervals and can be accessed over the World Wide Web interface at the following URL: http://144.16.71.148/cadb/. 相似文献
14.
Saikrishnan K Jeyakanthan J Venkatesh J Acharya N Sekar K Varshney U Vijayan M 《Journal of molecular biology》2003,331(2):385-393
Single-stranded DNA-binding protein (SSB) is an essential protein necessary for the functioning of the DNA replication, repair and recombination machineries. Here we report the structure of the DNA-binding domain of Mycobacterium tuberculosis SSB (MtuSSB) in four different crystals distributed in two forms. The structure of one of the forms was solved by a combination of isomorphous replacement and anomalous scattering. This structure was used to determine the structure of the other form by molecular replacement. The polypeptide chain in the structure exhibits the oligonucleotide binding fold. The globular core of the molecule in different subunits in the two forms and those in Escherichia coli SSB (EcoSSB) and human mitochondrial SSB (HMtSSB) have similar structure, although the three loops exhibit considerable structural variation. However, the tetrameric MtuSSB has an as yet unobserved quaternary association. This quaternary structure with a unique dimeric interface lends the oligomeric protein greater stability, which may be of significance to the functioning of the protein under conditions of stress. Also, as a result of the variation in the quaternary structure the path adopted by the DNA to wrap around MtuSSB is expected to be different from that of EcoSSB. 相似文献
15.
Fluorescence resonance energy transfer (FRET) microscopy imaging of live cell protein localizations 总被引:13,自引:0,他引:13
The current advances in fluorescence microscopy, coupled with the development of new fluorescent probes, make fluorescence resonance energy transfer (FRET) a powerful technique for studying molecular interactions inside living cells with improved spatial (angstrom) and temporal (nanosecond) resolution, distance range, and sensitivity and a broader range of biological applications. 相似文献
16.
Muktha B Srinivas O Amresh MR Guru Row TN Jayaraman N Sekar K 《Carbohydrate research》2003,338(19):2005-2011
The crystal structure of the title compound was determined by X-ray crystallography. The compound crystallized in the orthorhombic space group P2(1)2(1)2(1) with four molecules in the unit cell with a=9.170(2), b=9.873 (2), c=38.831(8) A. The structure was refined to a R index of 0.041 for 7907 independent reflections. The mannopyranose unit adopts a distorted 4C1 conformation. The structure depicts unique network of C-H...pi interactions, very closely resembling the pattern of O-H...O interactions in free sugars. This intriguing and rare observation points to a notion that the supramolecular organization pertaining to a sugar is in-built in the pyranose ring itself. 相似文献
17.
SUMMARY: A graphics package has been developed to display all side chain conformation angles of the user selected residue in a given protein structure. The proposed package is incorporated with all the protein structures (solved using X-ray diffraction and NMR spectroscopy) available in the Protein Data Bank. The package displays the multiple conformations adopted by a single amino acid residue whose structure is solved and refined at very high resolution. In addition, it shows the percentage distribution of the side chain conformation angles in different rotameric states. AVAILABILITY: http://144.16.71.146/cap/ 相似文献
18.
Chokkalingam Uvarani Karuppannan Arumugasamy Kumarasamy Chandraprakash Mathan Sankaran Athar Ata Palathurai Subramaniam Mohan 《化学与生物多样性》2015,12(3):358-370
Phytochemical investigation of the CHCl3 fraction of Swertia corymbosa resulted in the isolation of a new 3‐allyl‐2,8‐dihydroxy‐1,6‐dimethoxy‐9H‐xanthen‐9‐one ( 1 ), along with four known xanthones, gentiacaulein ( 3 ), norswertianin ( 4 ), 1,3,6,8‐tetrahydroxyxanthone ( 5 ), and 1,3‐dihydroxyxanthone ( 6 ). Structure of compound 1 was elucidated with the aid of IR, UV, NMR, and MS data, and chemical transformation via new allyloxy xanthone derivative ( 2 ). Compounds 1 – 6 exhibited various levels of antioxidant and anti‐α‐glucosidase activities. Absorption and fluorescence spectroscopic studies on 1 – 6 indicated that these compounds could interact with calf thymus DNA (CT‐DNA) through intercalation and with bovine serum albumin (BSA) in a static quenching process. Compound 1 was found to be significantly cytotoxic against human cancer cell lines HeLa, HCT116, and AGS, and weakly active against normal NIH 3T3 cell line. 相似文献
19.
Aenne S. Thormaehlen Christian Schuberth Hong-Hee Won Peter Blattmann Brigitte Joggerst-Thomalla Susanne Theiss Rosanna Asselta Stefano Duga Pier Angelica Merlini Diego Ardissino Eric S. Lander Stacey Gabriel Daniel J. Rader Gina M. Peloso Rainer Pepperkok Sekar Kathiresan Heiko Runz 《PLoS genetics》2015,11(2)
A fundamental challenge to contemporary genetics is to distinguish rare missense alleles that disrupt protein functions from the majority of alleles neutral on protein activities. High-throughput experimental tools to securely discriminate between disruptive and non-disruptive missense alleles are currently missing. Here we establish a scalable cell-based strategy to profile the biological effects and likely disease relevance of rare missense variants in vitro. We apply this strategy to systematically characterize missense alleles in the low-density lipoprotein receptor (LDLR) gene identified through exome sequencing of 3,235 individuals and exome-chip profiling of 39,186 individuals. Our strategy reliably identifies disruptive missense alleles, and disruptive-allele carriers have higher plasma LDL-cholesterol (LDL-C). Importantly, considering experimental data refined the risk of rare LDLR allele carriers from 4.5- to 25.3-fold for high LDL-C, and from 2.1- to 20-fold for early-onset myocardial infarction. Our study generates proof-of-concept that systematic functional variant profiling may empower rare variant-association studies by orders of magnitude. 相似文献
20.
Chidambaram Parameswari Rajasekaran Sripriya Karuppannan Veluthambi 《In vitro cellular & developmental biology. Plant》2010,46(5):395-402
In an analysis of 339 independent T
0 transgenic rice lines generated by Agrobacterium-mediated transformation, albino plants appeared in the T
1 generation in two single-copy transgenic lines, O54 and O36 and in one double-copy transgenic line, C18. While the T
0 plants of these three lines were green, albino and green plants emerged in a 1:3 ratio in the T
1 generation. The albino phenotype segregated as a monogenic recessive trait. Southern blot analysis of the green and albino
plants in the T
1 generation confirmed that the albino trait and the T-DNA insertion events were unlinked. Segregation of the albino trait
from the transgenic trait in the lines O54 and O36 was confirmed in T
2 and T
3 generations, respectively. Homozygous transgenic plants free from the albino trait were also identified. In the double-copy
transgenic line C18, we genetically separated the two transgenic loci, out-segregated the albino locus from both transgene
loci, and identified homozygous plants for each of the transgenic events by Southern blot analysis in the T
1 generation itself. Thus, we demonstrate that when an albino trait appears in the T
1 generation and is unlinked to a transgene locus, the albino locus can be segregated from the transgene locus and homozygous
transgenic lines free from albinos can be established. 相似文献