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101.
102.
Narayanan V Sandiford SL Wang Q Keren-Raifman T Levay K Slepak VZ 《Biochemistry》2007,46(23):6859-6870
The R7 family of RGS proteins (RGS6, -7, -9, -11) is characterized by the presence of three domains: DEP, GGL, and RGS. The RGS domain interacts with Galpha subunits and exhibits GAP activity. The GGL domain permanently associates with Gbeta5. The DEP domain interacts with the membrane anchoring protein, R7BP. Here we provide evidence for a novel interaction within this complex: between the DEP domain and Gbeta5. GST fusion of the RGS7 DEP domain (GST-R7DEP) binds to both native and recombinant Gbeta5-RGS7, recombinant Gbetagamma complexes, and monomeric Gbeta5 and Gbeta1 subunits. Co-immunoprecipitation and FRET assays supported the GST pull-down experiments. GST-R7DEP reduced FRET between CFP-Gbeta5 and YFP-RGS7, indicating that the DEP-Gbeta5 interaction is dynamic. In transfected cells, R7BP had no effect on the Gbeta5/RGS7 pull down by GST-R7DEP. The DEP domain of RGS9 did not bind to Gbeta5. Substitution of RGS7 Glu-73 and Asp-74 for the corresponding Ser and Gly residues (ED/SG mutation) of RGS9 diminished the DEP-Gbeta5 interaction. In the absence of R7BP both the wild-type RGS7 and the ED/SG mutant attenuated muscarinic M3 receptor-mediated Ca2+ mobilization. In the presence of R7BP, wild-type RGS7 lost this inhibitory activity, whereas the ED/SG mutant remained active. Taken together, our results are consistent with the following model. The Gbeta5-RGS7 molecule can exist in two conformations: "closed" and "open", when the DEP domain and Gbeta5 subunit either do or do not interact. The closed conformation appears to be less active with respect to its effect on Gq-mediated signaling than the open conformation. 相似文献
103.
Vijaya Lakshmi Bodiga Sandhya Thokala Sita Mahalaxmi Kovur Sreedhar Bodiga 《Biological trace element research》2017,178(1):117-126
This study aimed to assess the protective roles of polysaccharides from Agaricus blazei Murill (ABP) against cadmium (Cd)-induced damage in chicken livers. A total of 80 Hy-Line laying chickens (7 days old) were randomly divided into four groups (n = 20). Group I (control) was fed with a basic diet and 0.2 ml saline per day, group II (Cd-treated group) was fed with a basic diet containing 140 mg/kg cadmium chloride (CdCl2) and 0.2 ml saline per day, group III (Cd + ABP-treated group) was fed with a basic diet containing 140 mg/kg CdCl2 and 0.2-ml ABP solution (30 mg/ml) per day via oral gavage, and group IV (ABP-treated group) was fed with 0.2-ml ABP solution (30 mg/ml) per day via oral gavage. The contents of Cd and malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), the messenger RNA (mRNA) levels of inflammatory cytokines and heat shock proteins (HSPs), the protein levels of HSPs, and the histopathological changes of livers were evaluated on days 20, 40, and 60. The results showed that Cd exposure resulted in Cd accumulating in livers and inhibiting the activities of antioxidant enzymes (SOD and GSH-PX). Cd exposure caused histopathological damage and increased the MDA content, the mRNA levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) and HSPs (HSP27, HSP40, HSP60, HSP70, and HSP90) and the protein levels of HSPs (HSP60, HSP70, and HSP90). ABP supplementation during dietary exposure to Cd reduced the histopathological damage and decreased the contents of Cd and MDA and the expression of inflammatory cytokines and HSPs and improved the activities of antioxidant enzymes. The results indicated that ABP could partly ameliorate the toxic effects of Cd on chicken livers. 相似文献
104.
B.?Vijaya?Pandiyan P.?DeepaEmail author P.?KolandaivelEmail author 《Journal of molecular modeling》2017,23(1):16
Thirteen X-ray crystal structures containing various non-covalent interactions such as halogen bonds, halogen–halogen contacts and hydrogen bonds (I?N, I?F, I?I, F?F, I?H and F?H) were considered and investigated using the DFT-D3 method (B97D/def2-QZVP). The interaction energies were calculated at MO62X/def2-QZVP and MP2/aug-cc-pvDZ level of theories. The higher interaction and dispersion energies (2nd crystal) of ?9.58 kcal mol?1 and ?7.10 kcal mol?1 observed for 1,4-di-iodotetrafluorobenzene bis [bis (2-phenylethyl) sulfoxide] structure indicates the most stable geometrical arrangement in the crystal packing. The electrostatic potential values calculated for all crystal structures have a positive σ-hole, which aids understanding of the nature of σ-hole bonds. The significance of the existence of halogen bonds in crystal packing environments was authenticated by replacing iodine atoms by bromine and chlorine atoms. Nucleus independent chemical shift analysis reported on the resonance contribution to the interaction energies of halogen bonds and halogen–halogen contacts. Hirshfeld surface analysis and topological analysis (atoms in molecules) were carried out to analyze the occurrence and strength of all non-covalent interactions. These analyses revealed that halogen bond interactions were more dominant than hydrogen bonding interactions in these crystal structures. 相似文献
105.
Satya RV Mukherjee A 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2008,5(4):618-629
The incomplete perfect phylogeny (IPP) problem and the incomplete perfect phylogeny haplotyping (IPPH) problem deal with constructing a phylogeny for a given set of haplotypes or genotypes with missing entries. The earlier approaches for both of these problems dealt with restricted versions of the problems, where the root is either available or can be trivially re-constructed from the data, or certain assumptions were made about the data. In this paper, we deal with the unrestricted versions of the problems, where the root of the phylogeny is neither available nor trivially recoverable from the data. Both IPP and IPPH problems have previously been proven to be NPcomplete. Here, we present efficient enumerative algorithms that can handle practical instances of the problem. Empirical analysis on simulated data shows that the algorithms perform very well both in terms of speed and in terms accuracy of the recovered data. 相似文献
106.
Ayhan Dogukan Nurhan Sahin Mehmet Tuzcu Vijaya Juturu Cemal Orhan Muhittin Onderci James Komorowski Kazim Sahin 《Biological trace element research》2009,131(2):124-132
The present study was conducted to investigate the effects of chromium histidinate (CrHis) against experimentally induced
type II diabetes and on chromium (Cr), zinc (Zn), selenium (Se), manganese (Mn), iron (Fe), and copper (Cu) in serum, liver,
and kidney of diabetic rats. The male Wistar rats (n = 60, 8 weeks old) were divided into four groups. Group I received a standard diet (12% of calories as fat); group II were
fed standard diet and received CrHis (110 mcg CrHis/kg body weight per day); group III received a high-fat diet (HFD; 40% of calories as fat) for 2 weeks and then
were injected with streptozotocin (STZ) on day 14 (STZ, 40 mg/kg i.p.; HFD/STZ); group IV were treated as group III (HFD/STZ)
but supplemented with 110 mcg CrHis/kg body weight per day. The mineral concentrations in the serum and tissue were determined
by atomic absorption spectrometry. Compared to the HFD/STZ group, CrHis significantly increased body weight and reduced blood
glucose in diabetic rats (p < 0.001). Concentrations of Cr, Zn, Se, and Mn in serum, liver, and kidney of the diabetic rats were significantly lower
than in the control rats (p < 0.0001). In contrast, higher Fe and Cu levels were found in serum and tissues from diabetic versus the non-diabetic rats
(p < 0.001). Chromium histidinate supplementation increased serum, liver, and kidney concentrations of Cr and Zn both in diabetic
and non-diabetic rats (p < 0.001). Chromium supplementation increased Mn and Se levels in diabetic rats (p < 0.001); however, it decreased Cu levels in STZ-treated group (p < 0.001). Chromium histidinate supplementation did not affect Fe levels in both groups (p > 0.05). The results of the present study conclude that supplementing Cr to the diet of diabetic rats influences serum and
tissue Cr, Zn, Se, Mn, and Cu concentrations. 相似文献
107.
Yang He Xiulian Guo Ran Lu Bei Niu Vijaya Pasapula Pei Hou Feng Cai Ying Xu Fang Chen 《Plant Cell, Tissue and Organ Culture》2009,98(1):11-17
Callus browning is a typical feature of callus cultures derived from the hypocotyl of Jatropha curcas. Brown callus results in decreased regenerative ability, poor growth and even death. In this study, we investigated the effect
of browning on callus morphology and biochemical indices. Light microscopy and scanning electron microscopy showed striking
differences in callus morphology. During browning, chlorophylls and carotenoids concentrations decreased steadily. Polyphenol
oxidase (PPO) and peroxidase (POD) enzymatic activities patterns were similar during callus culture with a higher activity
level at week 3 compared to week 2 or later weeks. Grey relation degree analysis indicated that PPO played a more important
role than POD in enzymatic callus browning. Polyacrylamide gel electrophoresis results showed differences between browning
and non-browning callus. Gas chromatography–mass spectrometry results showed that saturated and unsaturated fatty acid quantities
differed significantly but there was little difference in fatty acid composition between non-browning and browning callus.
Differences in 17, 18.4 and 25 kDa protein concentrations were also observed in browning and non-browning callus using sodium
dodecyl sulfate–polyacrylamide gel electrophoresis. 相似文献
108.
Guobao Zhang Pingda Ren Nathanael S. Gray Taebo Sim Xia Wang Yi Liu Jianwei Che Weitong Dong Shin-Shay Tian Mark L. Sandberg Tracy A. Spalding Russell Romeo Maya Iskandar Zhiliang Wang H. Martin Seidel Donald S. Karanewsky Yun He 《Bioorganic & medicinal chemistry letters》2009,19(23):6691-6695
A series of 4-amino-6-benzimidazole-pyrimidines was designed to target lymphocyte-specific tyrosine kinase (Lck), a member of the Src-family kinases (SFKs). These type II inhibitors were optimized using a cellular Lck-dependent proliferation assay and are capable of inhibiting Lck at single-digit nanomolar concentrations. This scaffold is likely to serve a valuable template for developing potent inhibitors of a number of SFKs. 相似文献
109.
Cui-Ping Cao Oliver Gailing Iskandar Z. Siregar Ulfah J. Siregar Reiner Finkeldey 《Tree Genetics & Genomes》2009,5(3):407-420
Shorea is the largest and most important genus of the Dipterocarpaceae. The genetic diversity and structure of nine Shorea species from two different locations, namely Nanjak Makmur in Sumatra and Sumalindo in Borneo, were evaluated using amplified
fragment length polymorphism (AFLP) markers. A total of 274 trees were investigated at 85 polymorphic AFLP loci. Levels of
genetic diversity of these species ranged from = 0.100 for S. acuminata to = 0.165 for S. blumutensis. The population of rare species S. blumutensis possessed the highest genetic diversity suggesting that geographically restricted species can have levels of genetic variation
comparable to closely related widespread common congeners. Analyses of molecular variance revealed that the genetic variation
was mainly found among species in both locations (57.7% in Sumatra; 56.3% in Borneo). The unweighted pairgroup method using
arithmetic averages dendrogram of all samples revealed an almost complete separation of species. Thus, AFLP markers proved
appropriate for phylogenetic studies of Shorea species. Specific markers have been detected showing high-frequency differences among species and between regions within
species. Sequence information of these markers can be used to develop specific polymerase chain reaction markers for wood
identification. The possibility of interspecific hybridization was discussed. 相似文献
110.
Vijaya Ramachandran Thiruvengadam Arumugam Robert Langley Rosa F. Hwang Pablo Vivas-Mejia Anil K. Sood Gabriel Lopez-Berestein Craig D. Logsdon 《PloS one》2009,4(10)