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51.
Phospholipid-Sensitive Ca2+ -Dependent Protein Kinase Preferentially Phosphorylates Serine-115 of Bovine Myelin Basic Protein 总被引:1,自引:0,他引:1
R. Scott Turner C.-H. Jen Chou† Gonzalo J. Mazzei Philip Dembure ‡ J. F. Kuo 《Journal of neurochemistry》1984,43(5):1257-1264
Phospholipid-sensitive Ca2+ -dependent protein kinase (PL-Ca-PK) and cyclic AMP-dependent protein kinase (A-PK) both preferentially phosphorylated serine residues of bovine myelin basic protein (MBP). Tryptic peptide maps of MBP phosphorylated by PL-Ca-PK or A-PK, however, revealed different phosphopeptides, suggesting a difference in the intramolecular substrate specificity for the two enzymes. Serine-115 of MBP, in the sequence (-Arg-Phe-Ser(115)-Trp-), was found to be a preferred and probably major phosphorylation site for PL-Ca-PK. Because serine-115 of bovine MBP corresponds to serine-113 of rabbit MBP, an in vivo phosphorylation site reported by Martenson et al. (1983), and PL-Ca-PK is present at a very high level in brain and myelin, it is suggested that the enzyme may be responsible for the in vivo phosphorylation of this and other sites in MBP. 相似文献
52.
Structural comparison of the two distinct sugar binding sites in wheat germ agglutinin isolectin II 总被引:12,自引:0,他引:12
C S Wright 《Journal of molecular biology》1984,178(1):91-104
53.
N. N. Wassimi T. G. Isleib G. L. Hosfield 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(4):449-454
Summary A full diallel cross among four diverse homozygous strains of dry edible beans (Phaseolus vulgaris L.) was evaluated for yield, protein content, and culinary quality traits in the F2 and F3 generations in two locations. Interpretation of diallel effects [Method 1 Model I] using a fixed-effect genetic model made it possible to combine data from two generations into a single analysis and quantify the relative contributions of additive and dominance genetic effects to general (GCA) and specific (SCA) combining abilities. GCA was found to arise from three potential sources: additive effects, dominance interactions at homozygous loci, and average dominance interactions in hybrids involving the parent in question. SCA was found to be a function solely of dominance. Additive effects were the primary determinant of GCA and were highly significant. Specific dominance interactions were significant for seed yield, cooked bean moisture content, and texture but not for protein content. Texture was the only trait for which the additive-dominance model failed to provide an adequate fit to the data, suggesting that texture is significantly affected by epistatic interaction. One cross (Brazil-2 × Sanilac) was identified that exhibited a large heterotic effect for seed yield although the parents' additive effects were nonsignificant. Such a nicking effect was attributed to complementation between the two parents.Cooperative investigations of the Agricultural Research Service, U.S. Department of Agriculture and Michigan State University, East Lansing, MI 48824. Part of a thesis submitted by the senior author in partial fulfillment of the requirements for the Ph.D. degree at Michigan State University. Approved for publication by the Michigan Agricultural Experiment Station as Journal Article No. 11791. Research supported by USAID under a Title XII Bean/Cowpea CRSP and cooperative with Washington State University, Pullman, WA99164 相似文献
54.
The home range ofTakydromus tachydromoides was studied in a grassland area from April 1977 to November 1978. The mean size of home range did not differ markedly between
sexes; 136.5 m2 for males and 130.8 m2 for females. Home ranges of adults overlapped greatly in each sex, and the lizard was considered to be non-territorial. Individuals
showed return movement to a definite area (sleeping site) within the home range, and the home range did not shift within a
year or between years. Characteristics of the home range of this grassland-inhabiting lizard were discussed in relation to
resource abundance and predation pressure. 相似文献
55.
The binding parameters of the oligomycin-sensitivity conferring protein (OSCP) in inside-out particles from beef heart mitochondria have been tested by means of two assays, the oligomycin-sensitive ATP-Pi exchange, and the oligomycin-sensitive ATP hydrolysis. The total number of OSCP binding sites in A particles was equal to 220 pmol/mg particle protein. Each mole of ATPase active site was able to bind 1.1 +/- 0.5 mol OSCP with Kd 1.7 nM. 相似文献
56.
A comparison of specific antibodies induced by unfolded actins modified either by oxidation or by arylation of lysine residues was reported. We have focused our work on binding properties with filamentous actin and located its preferential antigenic sites for the anti-arylated-actin antibodies in the C-part of the molecule. An interference of anti-oxidized actin antibodies upon actin polymerisation has also been reported. 相似文献
57.
The site specificity of the apicomplexans Gregarina cuneata and Gregarina sleini , in larval Tenebrio molitor was investigated. Gregarina cuneata was found to inhabit the anteriormost region of the larval midgut, while G. steini was restricted to the posterior portion of the intestine. The site specificity of the pair was conserved in single and concurrent infections. Interspecific interactions do not seem to be presently responsible for the resource partitioning by the 2 gregarine species. Key words. Gregarina, site specificity, Tenebrio molitor. 相似文献
58.
MICHAEL P. BEENTJES 《Marine Mammal Science》1989,5(3):281-297
Diurnal and seasonal haul-out patterns, site fidelity and activity budgets of individually identified Hooker's sea lions were studied for two years at Papanui Beach, Otago Peninsula, New Zealand.
Fourteen male sea lions were identified. Lengths ranged from 1.65 m–2.28 m and estimated ages from 2-11 yr. The population consisted of four sexually and socially mature (potentially breeding), eight sexually mature but socially immature and two immature males. Most haul-outs (95.6%) were by nine identifiable individuals (Residents) returning on a regular basis, suggesting a high degree of site specificity. Emigration and recruitment were low in relation to the length of the study. Daily arrivals (mean = 0844 h, SD = 1.49) and departures (mean = 1802 h, SD = 1.18) indicate nocturnal feeding. During March 1986 sea lions spent 43.8% of each day ashore (= 78% of daylight hours). Numbers of sea lions hauled out declined in both breeding seasons; in 1986/87 this was due to a decrease in haul-out frequency of resident animals. All but one of these sea lions returned after the breeding season.
Sea lions preferentially selected the middle and the extreme ends of the beach as haul-out sites. During winter use was made of the grass dunes as haul-out areas.
There were significant differences in the frequencies of behavioral activities between summer and winter; more time was allocated to resting in summer. 相似文献
Fourteen male sea lions were identified. Lengths ranged from 1.65 m–2.28 m and estimated ages from 2-11 yr. The population consisted of four sexually and socially mature (potentially breeding), eight sexually mature but socially immature and two immature males. Most haul-outs (95.6%) were by nine identifiable individuals (Residents) returning on a regular basis, suggesting a high degree of site specificity. Emigration and recruitment were low in relation to the length of the study. Daily arrivals (mean = 0844 h, SD = 1.49) and departures (mean = 1802 h, SD = 1.18) indicate nocturnal feeding. During March 1986 sea lions spent 43.8% of each day ashore (= 78% of daylight hours). Numbers of sea lions hauled out declined in both breeding seasons; in 1986/87 this was due to a decrease in haul-out frequency of resident animals. All but one of these sea lions returned after the breeding season.
Sea lions preferentially selected the middle and the extreme ends of the beach as haul-out sites. During winter use was made of the grass dunes as haul-out areas.
There were significant differences in the frequencies of behavioral activities between summer and winter; more time was allocated to resting in summer. 相似文献
59.
Haruaki Uchiyama Koichi Ohara Kazuko Haga Tatsuya Haga Arata Ichiyama 《Journal of neurochemistry》1990,54(6):1870-1881
Muscarinic acetylcholine receptors purified from porcine cerebra or atria were covalently labeled with [3H]propylbenzilylcholine mustard ([3H]PrBCM), and then the labeled receptors were subjected to limited hydrolysis with trypsin, V8 protease, and lysyl endopeptidase, followed by analysis involving sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorography, autoradiography, or immunostaining. The labeled peptides were located on the basis of their reactivity with antibodies raised against three synthetic peptides with partial sequences of the m1 or m2 receptor, and of their sensitivity to endoglycosidase F, which was taken as evidence that they contain glycosylation sites near the N terminus. The [3H]PrBCM-binding site in both cerebral and atrial receptors was found to be located between the N terminus and the second intracellular loop, because the size of the smallest deglycosylated peptide that contained both the [3H]PrBCM-binding and glycosylation sites was approximately 16 kDa. Cerebral receptors were 32P-phosphorylated with protein kinase C, and the major phosphorylation sites in cerebral muscarinic receptors were found to be located in a C-terminal segment including a part of the third intracellular loop, because a 32P-labeled peptide of 12-14 kDa reacted with anti-(m1 C-terminal peptide) antiserum. The presence of an intramolecular disulfide bond, probably between Cys 98 and Cys 178 in the first and second extracellular loops, respectively, was suggested by the finding that a peptide of approximately 17 kDa containing the [3H]PrBCM-binding site, but not the glycosylation sites, was partly converted to a peptide of approximately 12 kDa on treatment with beta-mercaptoethanol. 相似文献
60.
Evidence for Distinct 5-Hydroxytryptamine2 Binding Site Subtypes in Cortical Membrane Preparations 总被引:1,自引:1,他引:0
5-Hydroxytryptamine (5-HT) displays a sixfold higher affinity for 5-HT2 binding sites labeled by [3H]ketanserin in rat (IC50 = 200 +/- 40 nM) and human (IC50 = 190 +/- 50 nM) cortex than for 5-HT2 sites in bovine cortex (IC50 = 1,200 +/- 130 nM). The Hill slopes of the 5-HT competition curves are 0.67 +/- 0.04 in rat, 0.69 +/- 0.08 in human, and 0.96 +/- 0.02 in bovine cortex. Scatchard analysis of (+/-)-[3H]4-bromo-2,5-dimethoxyamphetamine ([3H]DOB) binding in the rat indicates a population of binding sites with a KD of 0.38 +/- 0.04 nM and a Bmax of 1.5 +/- 0.05 pmol/g tissue. In contrast, specific [3H]DOB binding cannot be detected in bovine cortical membranes. These data indicate that species variations exist in 5-HT2 binding site subtypes and that [3H]ketanserin appears to label a homogeneous population of 5-HT2 binding site subtypes in bovine cortex. 相似文献