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201.
Akhlaq A. Farooqui Tahira Farooqui Allan J. Yates Lloyd A. Horrocks 《Neurochemical research》1988,13(6):499-511
Protein kinase C has recently attracted considerable attention because of its importance in the control of cell division, cell differentiation, and signal transduction across the cell membrane. The activity of this enzyme is altered by several lipids such as diacylglycerol, free fatty acids, lipoxins, gangliosides, and sulfatides. These lipids may interact with protein kinase C either directly or through calcium ions and produce their regulatory effect (activation or inhibition) on the activities of the enzymes phosphorylated by this kinase. These processes widen our perspective of the regulation of intercellular and intracelluular communication.Abbreviations used (PK-C)
Protein kinase C
- (cAMP-PK)
cAMP dependent protein kinase
- (DAG)
diacylglycerol
- (PtdSer)
phosphatidylserine
- (InsP
3)
inositol 1,4,5-trisphosphate
- (PtdIns 4,5-P2)
inositol 4,5 bisphosphate
- (FFA)
free fatty acid
- (MBP)
myelin basic protein
- (ATP)
adenosine triphosphate
- (GTP)
guanine triphosphate
- (TPA)
12-tetradecanoylphorbol-13-acetate
- (EGF)
epidermal growth factor
- (PDGF)
platelet derived growth factor
- (NeuNAc)
and N-acetylneuraminic acid 相似文献
202.
Administration of low amounts of ethanol for a prolonged period increases rat brain synaptosomal (Na+–K+)-ATPase activity, the increase being less in the protein deficient rats. The adaptive mechanism to offset the stress imposed by the continued presence of ethanol seems to be depressed by low plane of nutrition. In vivo and in vitro effects of ethanol on (Na+–K+)ATPase seems to be different. 相似文献
203.
Scott T. Sayers Hock C. Yeoh Jerry A. McLane Irene R. Held 《Neurochemical research》1988,13(12):1125-1131
The acetylcholine receptor (AChR) content and the autorphosphorylation of the regulatory subunit of cyclic AMP-dependent protein kinase type II (R-II) were evaluated in rat soleus muscles at 24, 30 and 66 hr after surgical denervation by cutting the nerve at a short distance (short-nerve-stump) and at a long distance (long-nerve-stump) from the muscle. AChR content was based on the specific binding of [125I]alpha-bungarotoxin (BUTX); changes in the autophosphorylation of R-II were based upon the predominant in vitro32P-phosphorylation of a 56-Kd soluble protein in cytosolic fractions of solei. The AChR content and the32P-autophosphorylation of R-II were increased in samples from short-nerve-stump solei, but not from long-nerve-stump solei, after a denervation-time of 30 hr. This nerve-stump-length dependency indicates that the two denervation effects are not related to the immediate halt of impulse-evoked muscle contractility. Furthermore, the results show that alterations in the32P-autophosphorylation of R-II occurred before, as well as whenever, increases in the AChR content were found. Speculatively, this temporal relationship may be significant with respect to the potential role of R-II in gene expression.Abbreviations ACh
acetylcholine
- AChR
acetylcholine receptor(s)
- BUTX
alpha-bungarotoxin
- Kd
kilodalton
- PAGE
polyacrylamide gel electrophoresis
- R-II
regulatory subunit of cyclic AMP-dependent protein kinase type II
- SDS
sodium dodecyl sulfate 相似文献
204.
Morphological and seed protein analyses of 26 species of the generaLolium, Festuca andVulpia confirmed their close systematic affinities. Six inflorescence characters readily differentiatedFestuca fromLolium. Protein similarities betweenFestuca of sect.Bovinae and cross-pollinated species ofLolium, coupled with cytogenetic and crossability data, substantiate that they should be united into one genus.Vulpia had phenetic similarities with sect.Scariosae, Montanae andOvinae ofFestuca. Lolium, Festuca, andVulpia are most likely derived from a common ancestral form which was close toFestuca pratensis andLolium perenne. 相似文献
205.
D. S. Virk P. S. Virk B. K. Mangat G. Harinarayana 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1988,75(5):736-740
Summary Regression analysis was computed on the grain yield of 15 single cross F1 hybrids of pearl millet (Pennisetum typhoides (Burm.) S. & H.) evaluated in 20 environments at 19 sites in India to assess the nature of genotype X environment interactions. Linear, quadratic, cubic, twoand three-intersecting straight line models were examined for fit. The interactions of six hybrids viz. MH 110, MH 113, MH 114, MH 115, MH 120 and MBH 110 were explained by the linear regression model. The response of the remaining nine hybrids was largely non-linear. The two and three-intersecting straight line models fit better than the quadratic and cubic models and explained non-linearity of response. The two-intersecting straight line models fit for 6 hybrids MH 106, MH 107, MH 112, MH 116, MH 117 and BJ 104. The response of MH 109 was best explained by a three-intersecting straight line model, but there still existed a significant remainder variation. The truncation of environmental range by assuming moving division points was more efficient than the fixed division points for the segmental regression models. The stability of hybrid varieties on the best fitting model has been discussed. 相似文献
206.
The comparison of primary structures is extended to 22 cytochromesb orb
6, 12 cytochromesc
1 orf, and 8 Rieske FeS proteins. Conclusions are drawn as to their phylogenetic relationship as well as on conserved, functionally important amino acids and secondary structures. The results are in favor of two independent quinone binding sites at opposite surfaces of the membrane, topping one of the two hemes of cytochromeb each. 相似文献
207.
Roderick A. Capaldi Diego Gonzalez Halphen Yu-Zhong Zhang Wayne Yanamura 《Journal of bioenergetics and biomembranes》1988,20(3):291-311
There is a renewed interest in the structure and functioning of the mitochondrial respiratory chain with the realization that a number of genetic disorders result from defects in mitochondrial electron transfer. These so-called mitochondrial myopathies include diseases of muscle, heart, and brain. The respiratory chain can be fractionated into four large multipeptide complexes, an NADH ubiquinone reductase (complex I), succinate ubiquinone reductase (complex II), ubiquinol oxidoreductase (complex III), and cytochromec oxidase (complex IV). Mitochondrial myopathies involving each of these complexes have been described. This review summarizes compositional and structural data on the respiratory chain proteins and describes the arrangement of these complexes in the mitochondrial inner membrane. This biochemical information is provided as a framework for the diagnosis and molecular characterization of mitochondrial diseases. 相似文献
208.
Studies were conducted to determine the effect of dietary iron (Fe) levels ranging from a deficiency to an excess on the toxicity
of cadmium (Cd) in chicks. In Fe-deficient animals, cadmium was found to be more toxic than in Fe supplemented animals as
measured by growth. The liver Cd burdens were increased significantly in the presence of dietary Fe supplementation, and there
was a significant Cd−Fe interaction in the Cd concentration of the kidney, indicating that iron deficiency increased the concentration
of Cd in the kidneys of those chicks receiving this element. Cd tended to reduce the Fe concentration in both the liver and
kidney. The absorption of Cd as measured by the amount of109Cd that disappeared from an isolated duodenal segment in one h was not affected by the Fe content of the diet, but the amount
of isotope appearing in the liver compared to the amount present in the blood was increased in the Fe supplemented chicks.
Separation of the Cd binding ligands by column chromatography revealed that more of the Cd in the liver, but not the kidney,
was associated with ligands which eluted in a column volume that contained metallothionein in those chicks receiving Fe than
in the livers from Fe deficient animals. The inverse relationship between the amount of Cd bound to the metallothionein containing
fraction and toxicity may be related causally.
Paper No. 10538 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7601. The use
of trade names in this publication does not imply endorsement by the NC Agricultural Research Service of the products named
nor criticism of similar ones not mentioned. 相似文献
209.
Ira D. Bhattacharya M. F. Picciano John A. Milner 《Biological trace element research》1988,18(1):59-70
Human milk glutathione peroxidase (GPx) was purified 4500-fold using acetone precipitation and purification by repetitive
ion-exchange and gel filtration chromatography with an overall yield of 34%. Homogeneity was established by gel electrophoresis.
Using gel filtration, the molecular weight (mol wt) of the enzyme was estimated to be 92 kdalton (kD). The monomeric molecular
weight was estimated to b 23 kD from polyacrylamide gel electrophoresis, indicating that the native enzyme consists of four
identical subunits. The molecular weight of each subunit was supported by amino acid analysis. Selenium (Se) content of the
purified enzyme was 0.31%, in a stoichiometry of 3.7 g-atoms/mol. Data from these studies reveal that GPx provided approximately
22% of total milk Se, but only 0.025% of the total protein. 相似文献
210.
Most proteins located in chloroplasts are encoded by nuclear genes, synthesized in the cytoplasm, and transported into the organelle. The study of protein uptake by chloroplasts has greatly expanded over the past few years. The increased activity in this field is due, in part, to the application of recombinant DNA methodology to the analysis of protein translocation. Added interest has also been gained by the realization that the transport mechanisms that mediate protein uptake by chloroplasts, mitochondria and the endoplasmic reticulum display certain characteristics in common. These include amino terminal sequences that target proteins to particular organelles, a transport process that is mechanistically independent from the events of translation, and an ATP-requiring transport step that is thought to involve partial unfolding of the protein to be translocated. In this review we examine recent studies on the binding of precursors to the chloroplast surface, the energy-dependent uptake of proteins into the stroma, and the targeting of proteins to the thylakoid lumen. These aspects of protein transport into chloroplasts are discussed in the context of recent studies on protein uptake by mitochondria.Abbrevlations CAT
chloramphenicol acetyl transferase
- CCCP
carbonylcyanide m-chlorophenylhydrazone
- DHFR
dihydrofolate reductase
- EPSP
5-enol-pyruvylshikimate-3-phosphate
- ER
endoplasmic reticulum
- LHCP
light harvesting chlorophyll a/b apoprotein
- NPT
neomycin phosphotransferase
- oATP
adenosine-2,3-dialdehyde-5-triphosphate
- P-inorganic phosphate Rubisco
ribulose-1,5-bisphosphate carboxylase/oxygenase
- SSU
small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase
- SRP
signal recognition particle 相似文献