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1.
Cathrine Laustrup M?ller Rasmus Kj?bsted Pablo J. Enriori Thomas Elbenhardt Jensen Cecilia Garcia-Rudaz Sara A. Litwak Kirsten Raun J?rgen Wojtaszewski Birgitte Schjellerup Wulff Michael A. Cowley 《PloS one》2016,11(7)
The melanocortin system includes five G-protein coupled receptors (family A) defined as MC1R-MC5R, which are stimulated by endogenous agonists derived from proopiomelanocortin (POMC). The melanocortin system has been intensely studied for its central actions in body weight and energy expenditure regulation, which are mainly mediated by MC4R. The pituitary gland is the source of various POMC-derived hormones released to the circulation, which raises the possibility that there may be actions of the melanocortins on peripheral energy homeostasis. In this study, we examined the molecular signaling pathway involved in α-MSH-stimulated glucose uptake in differentiated L6 myotubes and mouse muscle explants. In order to examine the involvement of AMPK, we investigate α-MSH stimulation in both wild type and AMPK deficient mice. We found that α-MSH significantly induces phosphorylation of TBC1 domain (TBC1D) family member 1 (S237 and T596), which is independent of upstream PKA and AMPK. We find no evidence to support that α-MSH-stimulated glucose uptake involves TBC1D4 phosphorylation (T642 and S704) or GLUT4 translocation. 相似文献
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3.
In order to determine the vector species of tsutsugamushi disease in Korea, chiggers were individually dissected, and internal contents were tested for Rickettsia tsutsugamushi organisms by means of indirect FA test, and each exoskeleton was mounted on slide for identification. Among 4,142 chiggers collected from 48 Apodemus agrarius at nine different localities during the period of July-November, 1989, 990 chiggers of 10 species of Trombiculidae were dissected and tested. Rickettsiae were confirmed in two Leptotrombidium pallidum larvae out of 447 tested, giving 0.4% of the infection rate. The chiggers of the other species tested were found negative. 相似文献
4.
Functional relationship among the gene clusters encoding F7(1), F7(2), F9, and F11 fimbriae of human uropathogenic Escherichia coli. 总被引:8,自引:3,他引:5
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I Van Die I Van Megen E Zuidweg W Hoekstra H De Ree H Van den Bosch H Bergmans 《Journal of bacteriology》1986,167(1):407-410
The P fimbrial gene clusters encoding the serologically different F7(1), F7(2), F9, and F11 fimbriae were compared functionally. The results show that these gene clusters are closely related. 相似文献
5.
The centromere-like parC locus of plasmid R1 总被引:1,自引:0,他引:1
6.
Rasmus H. Fogh Dick Schipper Rolf Boelens Robert Kaptein 《Journal of biomolecular NMR》1995,5(3):259-270
Summary The 1H, 13C and 15N NMR resonances of serine protease PB92 have been assigned using 3D tripleresonance NMR techniques. With a molecular weight of 27 kDa (269 residues) this protein is one of the largest monomeric proteins assigned so far. The side-chain assignments were based mainly on 3D H(C)CH and 3D (H)CCH COSY and TOCSY experiments. The set of assignments encompasses all backbone carbonyl and CHn carbons, all amide (NH and NH2) nitrogens and 99.2% of the amide and CHn protons. The secondary structure and general topology appear to be identical to those found in the crystal structure of serine protease PB92 [Van der Laan et al. (1992) Protein Eng., 5, 405–411], as judged by chemical shift deviations from random coil values, NH exchange data and analysis of NOEs between backbone NH groups.Abbreviations 2D/3D/4D
two-/three-/four-dimensional
- HSQC
heteronuclear single-quantum coherence
- HMQC
heteronuclear multiple-quantum coherence
- COSY
correlation spectroscopy
- TOCSY
total correlation spectroscopy
- NOE
nuclear Overhauser enhancement (connectivity)
- NOESY
2D NOE spectroscopy
Experiment nomenclature (H(C)CH, etc.) follows the conventions used elsewhere [e.g. Ikura et al. (1990) Biochemistry, 29, 4659–4667]. 相似文献
7.
Comparison of ccd of F, parDE of RP4, and parD of R1 using a novel conditional replication control system of plasmid R1 总被引:5,自引:2,他引:3
Rasmus Bugge Jensen Elisabeth Grohmann Helmut Schwab Ramón Díaz-Orejas Kenn Gerdes 《Molecular microbiology》1995,17(2):211-220
A number of plasmid-encoded gene systems are thought to stabilize plasmids by killing plasmid-free cells (also termed post-segregational killing or plasmid addiction). Here we analyse the mechanisms of plasmid stabilization by ccd of F, parDE of RP4 and parD of R1, and compare them to hok/sok of R1. To induce synchronous plasmid loss we constructed a novel plasmid replication-arrest system, which possesses the advantage that plasmid replication can be completely arrested by the addition of IPTG, a non-metabolizable inducer. Using isogenic plasmid constructions we have found, for the first time, consistent correlation between the effect on steady-state loss rates and the effect on cell proliferation in the plasmid replication-arrest assay for all three systems. The parDE system had the most pronounced effect both on plasmid stabilization and on plasmid retention after replication arrest. In contrast, ccd and parD both exhibited weaker effects than anticipated from previously published results. Thus, our results indicate that the function and efficiencies of some of the systems should be reconsidered. Our results are consistent with the previously postulated hypothesis that ccd and parDE act by killing plasmid-free segregants, whereas parD seems to act by inhibiting cell division of plasmid-free segregants. 相似文献
8.
P F Franck J M De Ree B Roelofsen J A Op den Kamp 《Biochimica et biophysica acta》1984,778(3):405-411
The non-specific phospholipid transfer protein purified from bovine liver has been used to modify the phospholipid content and phospholipid composition of the membrane of intact human erythrocytes. Apart from an exchange of phosphatidylcholine between the red cell and PC-containing vesicles, the protein appeared to facilitate net transfer of phosphatidylcholine from the donor vesicles to the erythrocyte and sphingomyelin transfer in the opposite direction. Phosphatidylcholine transfer was accompanied by an equivalent transfer (on a molar basis) of cholesterol. An increase in phosphatidylcholine content in the erythrocyte membrane from 90 to 282 nmol per 100 microliters packed cells was observed. Phospholipase C treatment of modified cells showed that all of the phosphatidylcholine which was transferred to the erythrocyte was incorporated in the lipid bilayer. The nonspecific lipid transfer protein used here appeared to be a suitable tool to modify lipid content and composition of the erythrocyte membrane, and possible applications of this approach are discussed. 相似文献
9.
The presence of peptidergic neuronal networks in the brain and the modulating action of neuropeptides on brain functions as evidenced by their behavioral influence in particular support the concept that the brain like the peripheral endocrine glands is an endocrine target organ which is as sensitive to treatment with neuropeptides as the peripheral glands are to pituitary hormones. Animal and human data are reviewed showing that neuropeptides related to ACTH/MSH affect motivational and attentional processes and that those related to vasopressin are involved in memory processes. Since these functions decline during aging it is postulated that a decreased bioavailability of neuropeptides in brain of elderly people is associated with specific disturbances in mental performance. Thus, the decreased mental ability of the aged may be restored by treatment with neuropeptides particularly those with little, if any, peripheral, endocrine activity, like the ACTH neuropeptide Org 2766 and the vasopressin neuropeptide DGAVP. 相似文献
10.
Fred A. Opmeer J. Peter H. Burbach Victor M. Wiegant Jan M. van Ree 《Life sciences》1982,31(4):323-328
The influence of chronic morphine exposure on the biotransformation of β-endorphin (βE) was investigated using the myenteric plexus-longitudinal muscle of guinea-pig ileum. A membrane preparation was incubated with βE and the degradation of βE as well as the accumulation of several βE fragments in the incubation medium were followed with time. The levels of peptides were determined by specific radioimmunoassays after separation by high-pressure liquid chromatography. It was found that exposure to morphine did not affect the disappearance of βE, but altered the time course of accumulation of βE fragments. In fact, the accumulation of γ-endorphin, α-endorphin and des-tyrosine1-α-endorphin was enhanced, while that of des-tyrosine1-γ-endorphin was not changed. Additionally, the disappearance of γ-endorphin appeared to be stimulated by morphine exposure. These data provide evidence that the fragmentation of βE is changed by chronic morphine exposure in such a way that the turn-over of γ-endorphin is increased. 相似文献