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91.
92.
The alpha subunit of type II Ca2+/calmodulin-dependent protein kinase is highly conserved in Drosophila 总被引:2,自引:0,他引:2
A monoclonal antibody against rat brain type II Ca2+/calmodulin-dependent protein kinase (CaM kinase) precipitates three proteins from Drosophila heads with apparent molecular weights similar to those of the subunits of the rat brain kinase. Fly heads also contain a CaM kinase activity that becomes partially independent of Ca2+ after autophosphorylation, as does the rat brain kinase. We have isolated a Drosophila cDNA encoding an amino acid sequence that is 77% identical to the sequence of the rat alpha subunit. All known autophosphorylation sites are conserved, including the site that controls Ca(2+)-independent activity. The gene encoding the cDNA is located between 102E and F on the fourth chromosome. The protein product of this gene is expressed at much higher levels in the fly head than in the body. Thus, both the amino acid sequence and the tissue specificity of the mammalian kinase are highly conserved in Drosophila. 相似文献
93.
To refine the linkage map of distal mouse Chromosome 12, we have identified DNA restriction fragment variants associated with a creatine kinase gene (Ck-3), the Akt proto-oncogene, an Abelson proviral integration site (D12N1), and the immunoglobulin heavy chain VH3609 variable region family (Igh-V36). The patterns of inheritance of these markers in backcross progeny and recombinant inbred mouse strains allowed their localization with respect to previously mapped genes to yield the linkage map: Aat-15.8 cM-Ck-3-0.9 cM-(Crip, Akt, Igh-C)-0.3 cM-(D12N1, Igh-V). This map confirms genetically the localization of the Igh-V gene complex distal to Igh-C on the chromosome. It differs from previous maps in placing D12N1 distal to Igh-C, and in suggesting that the Igh-V gene complex spans less than one centiMorgan (cM).Other DNA sequence variants detected with the creatine kinase probe allowed definition of four additional genetic loci: Ck-1 near Lmyc-1 on Chromosome 4; Ck-2 between Upg-1 and Hprt-ps1 (D17Rp10) on distal Chromosome 17; Ck-4 near Mpmv-17 and Mls-3 on Chromosome 16; and Ck-5 near Hba on Chromosome 11. 相似文献
94.
The gelation of sickle hemoglobin includes the formation of spherulitic arrays of polymers, known as polymer domains, which are an intrinsic result of the polymer formation mechanism. We have observed the diffusion of monomers into domains as they form, which substantially increases the total concentration of hemoglobin within the domain. The maximum total concentration attained is comparable with the pellet concentration of 0.5-0.55 g/cm3 obtained in sedimentation experiments. The half time for this process is approximately 50 s for domains of 25 microns radius, and is approximately independent of temperature. The shape of the diffusion progress curves as well as the deduced diffusion constants, and their weak temperature dependence are consistent with a simple model of hemoglobin monomer diffusion into the domain. 相似文献
95.
Based upon its superior catalytic activity for H2O2 decomposition, a bituminous coal-based activated carbon was selected for investigations of pretreatment and enzyme immobilization methods. Pretreatments considered include acid washing, exposure to strong oxidizing agents, contact with concentrated peroxide solutions, nitration and amination, isothiocyanate derivatization, silanization, and stearic acid coating. Effects of these pretreatments on morphology and trace-metal content of the carbon pellets have been studied using scanning electron microscopy and dispersive analysis of x rays. Immobilization of glucoamylase by adsorption, glutaraldehyde crosslinking, and covalent attachment to carbon activated by water-soluble diimide or diazotization have been examined. These different enzyme-carbon catalysts have been characterized by their enzyme loading, enzyme activity, catalytic activity for H2O2 decomposition, or combinations of these measures of performance. 相似文献
96.
For detection of ABO substances in the saliva of the cynomolgus monkey, the mixed cell agglutination reaction (MCAR) gave specific and clear results with a very small amount of saliva. Anti-A and anti-B antibodies in the sera of the same species showed the clearest hemagglutination by the saline agglutination method. The combined use of both methods was demonstrated to be easily and accurately applicable to the determination of human-type ABO blood groups of the cynomolgus monkey. 相似文献
97.
Cerebroside sulfate (CS) appears to fulfill most of the structural requirements of a hypothetical opiate receptor. It possesses many of the properties that are thought to be necessary for the identification of an "opiate receptor," exhibiting high affinity and stereoselective binding to a number of narcotic drugs. Although these properties are insufficient to establish identity of the receptor, it is highly significant that the affinity of this binding can be correlated with the analgetic potency of these drugs in both man and rodents. CS is an endogenous component of brain tissue, and a partially purified opiate receptor from mouse brain has been found to be CS. Other experiments indicate that reduced availability of brain CS decreases the analgetic effects of morphine and this is accompanied by a reduction in number of binding sites, suggesting that the interaction of opiates with CS observed in vitro may also have importance in vivo. CS was also found to be a component of the opiate receptor after marking with 125I-labeled diazosulfanilic acid. The possibility that CS or the SO4-2 group of this lipid may be the "anionic site" of the opiate receptor should be considered. 相似文献
98.
99.
Sunkyu Choi Kun Cho Kyungmoo Yea Jeonghwa Lee Jeongkwon Kim 《Biochemical and biophysical research communications》2009,383(1):135-140
Hypoxia during the expansion of adipocytes is known to contribute both to the secretion of multiple inflammation-related adipokines as well as to obesity. We therefore investigated the nature of protein changes occurring in adipocytes during hypoxia by observation of the intracellular proteins that are expressed in 3T3-L1 adipocytes. Lysates were utilized for quantitative proteome analysis using isobaric tags for relative and absolute quantitation (iTRAQ) combined with peptide separation by multi-dimensional liquid chromatography. Antioxidants and elongation factors, as well as glycolytic enzymes were increased in hypoxic adipocytes. These changes were supported by similar changes suggested by real-time PCR. The proteins showing changes are all potential targets for revering the mechanism behind the phenomenon of induction of obese adipocytes by hypoxia. This study can therefore aid in defining the proteomic changes that occur in adipocytes in response to oxygen stress, and can further characterize adipocyte metabolism and adaptation to low oxygen conditions. 相似文献
100.