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91.
92.
Sajish M Zhou Q Kishi S Valdez DM Kapoor M Guo M Lee S Kim S Yang XL Schimmel P 《Nature chemical biology》2012,8(6):547-554
Interferon-γ (IFN-γ) engenders strong antiproliferative responses, in part through activation of p53. However, the long-known IFN-γ-dependent upregulation of human Trp-tRNA synthetase (TrpRS), a cytoplasmic enzyme that activates tryptophan to form Trp-AMP in the first step of protein synthesis, is unexplained. Here we report a nuclear complex of TrpRS with the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) and with poly(ADP-ribose) polymerase 1 (PARP-1), the major PARP in human cells. The IFN-γ-dependent poly(ADP-ribosyl)ation of DNA-PKcs (which activates its kinase function) and concomitant activation of the tumor suppressor p53 were specifically prevented by Trp-SA, an analog of Trp-AMP that disrupted the TrpRS-DNA-PKcs-PARP-1 complex. The connection of TrpRS to p53 signaling in vivo was confirmed in a vertebrate system. These and further results suggest an unexpected evolutionary expansion of the protein synthesis apparatus to a nuclear role that links major signaling pathways. 相似文献
93.
94.
A. Gholizadeh M. H. Faizi B. BaghbanKohnehrouz H. C. Kapoor 《Russian Journal of Plant Physiology》2008,55(4):521-529
In proteobacterial cytosol, ClpS protein is known as a molecular adaptor for substrate selectivity and proteolytic activity of the ATP-dependent chaperone-protease complex, ClpAP. ClpA-related ClpS is a small protein usually encoded immediately upstream of ClpA in the genome of proteobacteria. Recent bioinformatics analysis has revealed the presence of cyanobacterial-type ClpS or ClpC-related ClpS in organisms lacking ClpA, including all the plant species sequenced to date. Here we report the identification of an actinobacterial homologue of the ClpS (possibly Clp-related) gene from a plant system. A cDNA, spanning 566 bp with a complete coding region corresponding to 132 amino acids, was isolated from a Celosia cristata expression library constructed on a λ TriplEX2 vector. This cDNA product was considered to be an ATP-dependent Clp protease adaptor and was designated as Celosia actinobacterial-type ClpS, since it contains a highly conserved domain belonging to the ClpS family of proteins from actinobacteria. Celosia ClpS is about 80% identical to actinobacterial ClpS proteins in its overall deduced amino acid sequence. Based on this finding, we may define a novel target of ATP-dependent Clp complex in a plant system or speculate the presence of a second type of molecular chaperone besides ClpC in plants, as predicted for actinobacteria. 相似文献
95.
Kapoor S 《Journal of cellular and molecular medicine》2008,12(4):1420-1420
96.
Kapoor P Sahasrabuddhe AA Kumar A Mitra K Siddiqi MI Gupta CM 《The Journal of biological chemistry》2008,283(33):22760-22773
Leishmania actin was cloned, overexpressed in baculovirus-insect cell system, and purified to homogeneity. The purified protein polymerized optimally in the presence of Mg2+ and ATP, but differed from conventional actins in its following properties: (i) it did not polymerize in the presence of Mg2+ alone, (ii) it polymerized in a restricted range of pH 7.0-8.5, (iii) its critical concentration for polymerization was found to be 3-4-fold lower than of muscle actin, (iv) it predominantly formed bundles rather than single filaments at pH 8.0, (v) it displayed considerably higher ATPase activity during polymerization, (vi) it did not inhibit DNase-I activity, and (vii) it did not bind the F-actin-binding toxin phalloidin or the actin polymerization disrupting agent Latrunculin B. Computational and molecular modeling studies revealed that the observed unconventional behavior of Leishmania actin is related to the diverged amino acid stretches in its sequence, which may lead to changes in the overall charge distribution on its solvent-exposed surface, ATP binding cleft, Mg2+ binding sites, and the hydrophobic loop that is involved in monomer-monomer interactions. Phylogenetically, it is related to ciliate actins, but to the best of our knowledge, no other actin with such unconventional properties has been reported to date. It is therefore suggested that actin in Leishmania may serve as a novel target for design of new antileishmanial drugs. 相似文献
97.
Shuklangi A. Kulkarni Vandana Ghormade Girish Kulkarni Manisha Kapoor Santosh B. Chavan Armugam Rajendran 《Biocontrol Science and Technology》2008,18(8):809-828
Metarhizium isolates from soil (53) and insect hosts (10) were evaluated for extracellular production of cuticle degrading enzyme (CDE) activities such as chitinase, chitin deacetylase (CDA), chitosanase, protease and lipase. Regression analysis demonstrated the relation of CDE activities with Helicoverpa armigera mortality. On basis of this relation, ten isolates were selected for further evaluation. Subsequently, based on LT50 of the 10 isolates towards H. armigera, five isolates were selected. Out of these five isolates, three were selected on the basis of higher conidia production (60–75 g/kg rice), faster sedimentation time (ST50) (2.3–2.65 h in 0.1% (w/v) Tween 80) and lower LC50 (1.4–5.7×103 conidia/mL) against H. armigera. Finally, three Metarhizium isolates were selected for the molecular fingerprinting using ITS sequencing and RAPD patterning. All three isolates, M34412, M34311 and M81123, showed comparable RAPD patterns with a 935G primer. These were further evaluated for their field performance against H. armigera in a chickpea crop. The percent efficacies with the three Metarhizium isolates were from 65 to 72%, which was comparable to the chemical insecticide, endosulfan (74%). 相似文献
98.
Deepika Sharma Rupam Kapoor Ashok K. Bhatnagar 《World journal of microbiology & biotechnology》2008,24(3):395-400
Curculigo orchioides Gaertn. (family Hypoxidaceae) is an endangered anticarcinogenic and aphrodisiac herb, native of India. This study reports
the effect of three arbuscular mycorrhizal (AM) fungal inocula on post-transplanting performance of ‘in vitro’ raised C. orchioides plantlets. The three AM fungal inocula consisted of two monospecific cultures of Glomus geosporum and G. microcarpum and one crude consortium of AM fungal spores isolated from rhizosphere soil of C. orchioides growing in natural habitat. Complete plantlets of C. orchioides were raised by direct organogenesis of leaf explants on half strength Murashige and Skoog’s medium devoid of any growth hormone.
C. orchioides plantlets responded significantly different to all three mycorrhizal treatments. Mycorrhization enhanced the survival rate
of C. orchioides plantlets to 100%. The inoculated plantlets fared significantly better than the uninoculated ones in terms of biomass production
and number of leaves and roots per plant. Mycorrhizal plantlets exhibited higher concentrations of photosynthetic pigments
as well as minerals P, Mg, Cu, Zn, Mn and Fe in both shoots and roots. Among the three inocula tested, plantlets inoculated
with the mixed consortium of AM fungi consistently performed better in terms of the parameters evaluated. The study suggests
use of mixed consortium of AM fungi over monospecific cultures for the sustainable cultivation and conservation of endangered
medicinal plant: Curculigo orchioides. 相似文献
99.
The natural occurrence of conservative residue substitutions in proteins suggests that side-chain packing schemes in protein interiors can accommodate mutational replacements of residues by others of similar nature. To explore the extent to which such substitutions are tolerated, especially when introduced simultaneously and globally over the entire length of a polypeptide chain, we examined the conformational behavior of a model 65 residues-long protein, wild-type chymotrypsin inhibitor 2 (WTCI2), and two globally-mutated (GM) variants named GMCI2-1 and GMCI2-2, each incorporating 55 conservative residue substitutions. GMCI2-1, was soluble over a wide range of pH, and folded into a compact, spherical, monomer marked by (i) complete absence of surface hydrophobicity, (ii) a WTCI2-like betaII-type CD spectrum, (iii) high WTCI2-like thermal stability, and (d) 1D and 2D NMR spectra characteristic of folded protein structure. GMCI2-2 was insoluble over a wide range of pH, and could be solubilized only at pH 4.0, showing non-WTCI2-like far-UV CD spectra characterized by high helical content. These results tentatively indicate that polypeptides incorporating residues of identical nature at equivalent chain locations can show the potential to fold with similar characteristics. However, further detailed investigations would be required to determine whether indeed the structural fold of GMCI2-1 resembles that of WTCI2, and to evaluate the extent to which it does so. 相似文献
100.
Dharmesh S. Kapoor G. Willy Davila Raul J. Rosenthal Gamal M. Ghoniem 《Obesity (Silver Spring, Md.)》2004,12(7):1104-1107
Objective: The objective of this study was to evaluate the impact of obesity on pelvic floor function in women. Research Methods and Procedures: This was a prospective controlled study of 20 morbidly obese female patients planning to undergo gastric bypass surgery and 20 age‐matched female controls. Subjects completed symptom and impact questionnaires, including the Incontinence Impact Questionnaire (IIQ‐7), Urogenital Distress Inventory (UDI), the Kobashi Prolapse Symptom Inventory and Quality‐of‐Life Questionnaire (PSI‐QOL), and Index of Female Sexual Function. Data were analyzed with Wilcoxon or ratio χ2 tests. Results: Mean weight was 295.7 ± 87.9 lbs in the study group and 144.79 ± 33.07 lbs in the control group. Mean BMI was 52.65 ±14.49 kg/m2 in the study group and 25.11 ± 5.27 kg/m2 in the control group. According to the IIQ‐7, urinary incontinence significantly affected lifestyle in the study group. The total IIQ‐7 score was also significantly affected in the study group (p = 0.03). The UDI indicated more urinary leakage with activity (p = 0.04) and more incidents of small amounts of leakage (p = 0.02) in the study group. According to the PSI‐QOL, women in the study group experienced constipation more often because of difficulty in emptying the rectum (p = 0.04). The PSI‐QOL score was higher in the study group (6.75 ± 6.84) than in the control group (2.65 ± 3.03; p = 0.04). There were no significant differences between groups regarding sexual function. Discussion: Morbid obesity is associated with a significant negative impact on urogenital health. Sexual function did not seem to be affected in women who are morbidly obese. 相似文献