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31.
Spooner PJ Sharples JM Goodall SC Seedorf H Verhoeven MA Lugtenburg J Bovee-Geurts PH DeGrip WJ Watts A 《Biochemistry》2003,42(46):13371-13378
High-resolution solid-state NMR methods have been used to analyze the conformation of the chromophore in the late photointermediate metarhodopsin-I, from observation of (13)C nuclei introduced into the beta-ionone ring (at the C16, C17, and C18 methyl groups) and into the adjoining segment of the polyene chain (at C8). Bovine rhodopsin in its native membrane was also regenerated with retinal that was (13)C-labeled close to the 11-Z bond (C20 methyl group) to provide a reporter for optimizing and quantifying the photoconversion to metarhodopsin-I. Indirect photoconversion via the primary intermediate, bathorhodopin, was adopted as the preferred method since approximately 44% conversion to the metarhodopsin-I component could be achieved, with only low levels (approximately 18%) of ground-state rhodopsin remaining. The additional photoproduct, isorhodopsin, was resolved in (13)C spectra from C8 in the chain, at levels of approximately 38%, and was shown using rotational resonance NMR to adopt the 6-s-cis conformation between the ring and the polyene chain. The C8 resonance was not shifted in the metarhodopsin-I spectral component but was strongly broadened, revealing that the local conformation had become less well defined in this segment of the chain. This line broadening slowed rotational resonance exchange with the C17 and C18 ring methyl groups but was accounted for to show that, despite the chain being more relaxed in metarhodopsin-I, its average conformation with respect to the ring was similar to that in the ground state protein. Conformational restraints are also retained for the C16 and C17 methyl groups on photoactivation, which, together with the largely preserved conformation in the chain, argues convincingly that the ring remains with strong contacts in its binding pocket prior to activation of the receptor. Previous conclusions based on photocrosslinking studies are considered in view of the current findings. 相似文献
32.
A novel mechanism of repression of the vascular endothelial growth factor promoter,by single strand DNA binding cold shock domain (Y-box) proteins in normoxic fibroblasts 总被引:4,自引:0,他引:4 下载免费PDF全文
Coles LS Diamond P Lambrusco L Hunter J Burrows J Vadas MA Goodall GJ 《Nucleic acids research》2002,30(22):4845-4854
33.
34.
Shay Bracha Michael McNamara Ian Hilgart Milan Milovancev Jan Medlock Cheri Goodall Samanthi Wickramasekara Claudia S. Maier 《Analytical biochemistry》2014
Transitional cell carcinoma (TCC), the most common cancer of the urinary bladder in dogs, is usually diagnosed at an advanced disease stage with limited response to chemotherapy. Commercial screening tests lack specificity and current diagnostic procedures are invasive. A proof of concept pilot project for analyzing the canine urinary proteome as a noninvasive diagnostic tool for TCC identification was conducted. Urine was collected from 12 dogs in three cohorts (healthy, urinary tract infection, TCC) and analyzed using liquid chromatography tandem mass spectrometry. The presence of four proteins (macrophage capping protein, peroxiredoxin 5, heterogeneous nuclear ribonucleoproteins A2/B, and apolipoprotein A1) was confirmed via immunoblot. Of the total 379 proteins identified, 96 were unique to the TCC group. A statistical model, designed to evaluate the accuracy of this multiplex biomarker approach for diagnosis of TCC, predicted the presence of disease with 90% accuracy. 相似文献
35.
Lida E. Pimper C. Scott Baker R. Natalie P. Goodall Carlos Olavarría María I. Remis 《Conservation Genetics》2010,11(6):2157-2168
The Commerson’s dolphin, Cephalorhynchus commersonii, is found in shallow waters of the continental shelf off the eastern coast of South America between 40°S and 56°S. This species
is taken incidentally in artisanal gillnet fisheries, especially along the shallow coastline of northern Tierra del Fuego
and southern Patagonia. The biological importance of by-catch is likely to be underestimated if the boundaries of subpopulations
are not properly defined. Here, we report on the sequence variation of the mitochondrial DNA control region of the Commerson’s
dolphin from five areas defined in Tierra del Fuego, Argentina and Chile, to provide a preliminary assessment of population
structure where conservation efforts are most needed. A 466 bp fragment of the mitochondrial DNA control region was sequenced
from 196 samples of skin, teeth and bone, defining 20 haplotypes from 17 polymorphic sites. Nucleotide (π = 0.40%) and haplotype (h = 0.807) diversity were low compared to some other odontocete populations, but similar to that of other species of this genus.
Genetic differentiation evaluated through analyses of molecular variance (AMOVA) showed significant overall differences among
areas within Tierra del Fuego (Φ
ST
= 0.059, P < 0.01). An analysis of sex-specific population structure suggested that the dispersal rates of both females and males are
low, indicative of females displaying greater site fidelity. The results from mtDNA control region sequences alone revealed
significant differentiation among studied areas, which should be considered as independent management units. We recommend
that the impact of localized gillnet mortalities should be managed on a local scale in these areas of Tierra del Fuego. 相似文献
36.
Ben M Minogue Stephen M Richardson Leo AH Zeef Anthony J Freemont Judith A Hoyland 《Arthritis research & therapy》2010,12(1):R22
Introduction
Nucleus pulposus (NP) cells have a phenotype similar to articular cartilage (AC) cells. However, the matrix of the NP is clearly different to that of AC suggesting that specific cell phenotypes exist. The aim of this study was to identify novel genes that could be used to distinguish bovine NP cells from AC and annulus fibrosus (AF) cells, and to further determine their expression in normal and degenerate human intervertebral disc (IVD) cells. 相似文献37.
The formation of self assembled nano-structures from the biopolymer laminarin dried onto mica is reported. The observed structures are composed of stacked terraced layers decreasing in size away from the mica surface. The layers display a high degree of dimensional regularity as observed using atomic force microscope imaging (AFM). The width of the layers is linearly dependent upon the number of layers in the structure and decreases with layer number away from the mica substrate. The thickness of the layers is uniform throughout the structure. A pore is contained in the central region of each structure with more than one layer. We postulate that these structures have potential use as templates in microelectronic devices and sensors where the central pore has the potential to immobilise functional materials. 相似文献
38.
39.
Francine Z Marques Simon PR Romaine Matthew Denniff James Eales John Dormer Ingrid M Garrelds Lukasz Wojnar Katarzyna Musialik Barbara Duda-Raszewska Bartlomiej Kiszka Magdalena Duda Brian J Morris Nilesh J Samani AH Jan Danser Pawel Bogdanski Ewa Zukowska-Szczechowska Fadi J Charchar Maciej Tomaszewski 《Molecular medicine (Cambridge, Mass.)》2015,21(1):739-748
MicroRNA-181a binds to the 3′ untranslated region of messenger RNA (mRNA) for renin, a rate-limiting enzyme of the renin-angiotensin system. Our objective was to determine whether this molecular interaction translates into a clinically meaningful effect on blood pressure and whether circulating miR-181a is a measurable proxy of blood pressure. In 200 human kidneys from the TRANScriptome of renaL humAn TissuE (TRANSLATE) study, renal miR-181a was the sole negative predictor of renin mRNA and a strong correlate of circulating miR-181a. Elevated miR-181a levels correlated positively with systolic and diastolic blood pressure in TRANSLATE, and this association was independent of circulating renin. The association between serum miR-181a and systolic blood pressure was replicated in 199 subjects from the Genetic Regulation of Arterial Pressure of Humans In the Community (GRAPHIC) study. Renal immunohistochemistry and in situ hybridization showed that colocalization of miR-181a and renin was most prominent in collecting ducts where renin is not released into the systemic circulation. Analysis of 69 human kidneys characterized by RNA sequencing revealed that miR-181a was associated with downregulation of four mitochondrial pathways and upregulation of 41 signaling cascades of adaptive immunity and inflammation. We conclude that renal miR-181a has pleiotropic effects on pathways relevant to blood pressure regulation and that circulating levels of miR-181a are both a measurable proxy of renal miR-181a expression and a novel biochemical correlate of blood pressure. 相似文献
40.
Nick R Love Yaoyao Chen Boyan Bonev Michael J Gilchrist Lynne Fairclough Robert Lea Timothy J Mohun Roberto Paredes Leo AH Zeef Enrique Amaya 《BMC developmental biology》2011,11(1):1-15