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151.
Masahiro Okazaki Nobuyuki Yanagihara Futoshi Izumi Yasuhide Nakashima Akio Kuroiwa 《Journal of neurochemistry》1989,52(1):222-228
The distribution and secretion of atrial natriuretic peptides (ANPs) were investigated in bovine adrenal medulla. (1) Cultured bovine adrenal medullary cells (2 x 10(6)/dish) contained 100.4 +/- 6.0 fmol of immunoreactive ANP (IR-ANP) and 207.3 +/- 6.6 nmol of catecholamines as epinephrine plus norepinephrine. (2) Stimulation of nicotinic but not muscarinic acetylcholine receptors caused a cosecretion of IR-ANP and catecholamines corresponding to the ratio of IR-ANP to catecholamines in cultured bovine adrenal medullary cells. (3) Carbachol-stimulated secretion of IR-ANP was dependent on the presence of extracellular Ca2+. (4) Chromaffin granules isolated from bovine adrenal medulla contained large amounts of IR-ANP and catecholamines, in the same ratio as did cultured adrenal medullary cells. (5) Reverse-phase HPLC analysis showed that both stored and secreted IR-ANP consisted of two components, which eluted at the position of ANP(99-126) or ANP(1-126). These results indicate that ANPs are stored as ANP(99-126) and ANP(1-126) in chromaffin granules, and are cosecreted in parallel with catecholamines in a Ca2+-dependent manner by the stimulation of nicotinic acetylcholine receptors. 相似文献
152.
A. Delprato B. Bonheur M.‐P. Algéo P. Rosay L. Lu R. W. Williams W. E. Crusio 《Genes, Brain & Behavior》2015,14(8):591-606
Variation in hippocampal neuroanatomy correlates well with spatial learning ability in mice. Here, we have studied both hippocampal neuroanatomy and behavior in 53 isogenic BXD recombinant strains derived from C57BL/6J and DBA/2J parents. A combination of experimental, neuroinformatic and systems genetics methods was used to test the genetic bases of variation and covariation among traits. Data were collected on seven hippocampal subregions in CA3 and CA4 after testing spatial memory in an eight‐arm radial maze task. Quantitative trait loci were identified for hippocampal structure, including the areas of the intra‐ and infrapyramidal mossy fibers (IIPMFs), stratum radiatum and stratum pyramidale, and for a spatial learning parameter, error rate. We identified multiple loci and gene variants linked to either structural differences or behavior. Gpc4 and Tenm2 are strong candidate genes that may modulate IIPMF areas. Analysis of gene expression networks and trait correlations highlight several processes influencing morphometrical variation and spatial learning. 相似文献
153.
Joanne Blanchfield Julie Dutton Ron Hogg David Craik David Adams Richard Lewis Paul Alewood Istvan Toth 《Letters in Peptide Science》2001,8(3-5):235-239
The -conotoxin MII is a 16 amino acid long peptide toxinisolated from the marine snail, Conus magus. This toxinhas been found to be a highly selective and potent inhibitorof neuronal nicotinic acetylcholine receptors of the subtype32. To improve the bioavailability of this peptide, we havecoupled to the N-terminus of conotoxin MII, 2-amino-D,L-dodecanoic acid (Laa) creating a lipidic linear peptide whichwas then successfully oxidised to produce the correctly foldedconotoxin MII construct. 相似文献
154.
Met-Lys-双C肽人胰岛素原基因的构建表达及分离纯化 总被引:2,自引:0,他引:2
应用 P C R 定点突变方法构建编码 M et Lys 双 C 肽人胰岛素原基因,并在大肠杆菌中以包含体方式获得表达 表达产物经还原、重组、 Sephadex G 75 分离纯化,获得 M et Lys 双 C 肽人胰岛素原,经胰蛋白酶与羧肽酶 B的酶解, Resource T M Q 阴离子交换柱层析分离制备得人胰岛素,其放免活性、受体结合活性均与猪胰岛素相同 相似文献
155.
Pheromone peptides are an important component of bacterial quorum‐sensing system. The pheromone peptide cOB1 (VAVLVLGA) of native commensal Enterococcus faecalis has also been identified as an antimicrobial peptide (AMP) and reported to kill the prototype clinical isolate strain of E. faecalis V583. In this study, the pheromone peptide cOB1 has shown to form amyloid‐like structures, a characteristic which is never reported for a pheromone peptide so far. With in silico analysis, the peptide was predicted to be highly amyloidogenic. Further, under experimental conditions, cOB1 formed aggregates displaying characteristics of amyloid structures such as bathochromic shift in Congo red absorbance, enhancement in thioflavin T fluorescence, and fibrillar morphology under transmission electron microscopy. This novel property of pheromone peptide cOB1 may have some direct effects on the binding of the pheromone to the receptor cells and subsequent conjugative transfer, making this observation more important for the therapeutics, dealing with the generation of virulent and multidrug‐resistant pathogenic strains. 相似文献
156.
Five disulfide bridges stabilize a hevein-type antimicrobial peptide from the bark of spindle tree (Euonymus europaeus L.) 总被引:4,自引:0,他引:4
Van den Bergh KP Proost P Van Damme J Coosemans J Van Damme EJ Peumans WJ 《FEBS letters》2002,530(1-3):181-185
A small 45 amino acid residue antifungal polypeptide was isolated from the bark of spindle tree (Euonymus europaeus L.). Though the primary structure of this so-called E. europaeus chitin-binding protein or Ee-CBP is highly similar to the hevein domain, it distinguishes itself from most previously identified hevein-type antimicrobial peptides (AMP) by the presence of two extra cysteine residues that form an extra disulfide bond. Due to these five disulfide bonds Ee-CBP is a remarkably stable protein. Agar diffusion and microtiterplate assays demonstrated that Ee-CBP is a potent antimicrobial protein. IC50-values as low as 1 μg/ml were observed for the fungus Botrytis cinerea. Comparative assays further demonstrated that Ee-CBP is a stronger inhibitor of fungal growth than Ac-AMP2 from Amaranthus caudatus seeds, which is considered one of the most potent antifungal hevein-type plant proteins. 相似文献
157.
158.
We describe methods for studying axo-dendritic projections, one of the forms of neural connection involved in the complex circuits of the central nervous system, including brainstem auditory pathways. This form of neural connection is often difficult to visualize by conventional tract tracing techniques. Retrogradely identified cells were filled intracellularly with a mixture of fluorescent Lucifer yellow and nonfluorescent HRP in live slice preparations to reveal the detailed morphological features of these cells with special attention to the distal dendrite that may receive projections from suspected or known input axons. Extracellular or intracellular labeling of cells with axons that project to the distal dendrite of the identified cells was accomplished in the same live slice preparation. Using a live slice rather than a fixed slice allows accurate, visually controlled placement of anterograde tracer, which requires living axons for transport, into the source of input to the identified cells within the slice. Live slices also permit one to characterize the identified cells electrophysiologically. Intracellular labeling of cells in a potential source of local input to the identified cells also provides conclusive information concerning with connections of the cells involved. 相似文献
159.
Complex I (CI) deficiency is the most common respiratory chain defect representing more than 30% of mitochondrial diseases. CI is an L-shaped multi-subunit complex with a peripheral arm protruding into the mitochondrial matrix and a membrane arm. CI sequentially assembled into main assembly intermediates: the P (pumping), Q (Quinone) and N (NADH dehydrogenase) modules. In this study, we analyzed 11 fibroblast cell lines derived from patients with inherited CI deficiency resulting from mutations in the nuclear or mitochondrial DNA and impacting these different modules. In patient cells carrying a mutation located in the matrix arm of CI, blue native-polyacrylamide gel electrophoresis (BN-PAGE) revealed a significant reduction of fully assembled CI enzyme and an accumulation of intermediates of the N module. In these cell lines with an assembly defect, NADH dehydrogenase activity was partly functional, even though CI was not fully assembled. We further demonstrated that this functional N module was responsible for ROS production through the reduced flavin mononucleotide. Due to the assembly defect, the FMN site was not re-oxidized leading to a significant oxidative stress in cell lines with an assembly defect. These findings not only highlight the relationship between CI assembly and oxidative stress, but also show the suitability of BN-PAGE analysis in evaluating the consequences of CI dysfunction. Moreover, these data suggest that the use of antioxidants may be particularly relevant for patients displaying a CI assembly defect. 相似文献
160.
Matsumoto N Tsuruoka S Iwamoto T Tomich JM Ito K Imai M Suzuki M 《The Journal of membrane biology》2003,193(3):195-200
To better understand the process of fluid movement driven by Cl– conductance, a Cl– channel-forming peptide was delivered to the luminal membrane of microperfused rabbit renal proximal tubules. When the peptide (NK4-M2GlyR) was perfused, a significant new conductance was observed within 3 min and stabilized at 10 min. Alteration of the ion composition revealed it to be a Cl–-specific conductance. Reabsorption of Cl– (J
Cl) was increased by NK4-M2GlyR, but not by a scramble NK4-M2GlyR sequence, suggesting that the active peptide formed de novo Cl– channels in the luminal membrane of the perfused tubules. In the presence of the peptide, reabsorption of fluid (J
v) was dramatically increased and J
Na and J
Ca were concomitantly increased. We propose that introduction of the new Cl– conductance in the luminal membrane leads to a coordinated efflux of water across the membrane and an increase in cation translocation via the paracellular pathway, resulting in an increase in J
v. This novel method could prove useful in characterizing mechanisms of fluid transport driven by Cl– gradients. 相似文献