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71.
Karien E. De Rooij Pia A. M. De Koning Gans Raymund A. C. Roos Gert-Jan B. Van Ommen Johan T. Den Dunnen 《Human genetics》1995,95(3):270-274
The mutation causing Huntington disease (HD) has been identified as an expansion of a polymorphic (CAG)
n
repeat in the 5 part of the huntingtin gene. The specific neuropathology of HD, viz. selective neuronal loss in the caudate nucleus and putamen, cannot be explained by the widespread expression of the gene. Since somatic expansion is observed in affected tissue in myotonic dystrophy, we have studied the length of the (CAG)
n
repeat in various regions of the brain. Although we have not found clear differences when comparing severely and mildly affected regions, we have observed a minor increase in repeat length upon comparison of affected brain samples with cerebellum or peripheral blood. Hence, although further somatic amplification seems to occur in affected areas of the brain, the differences between affected and unaffected regions are too small to make this mechanism an obvious candidate for the cause of differential neuronal degeneration in HD. 相似文献
72.
Anna Fietta Guido Grandi Massimo Malcovati Gianna Valentini Vittorio Sgaramella Antonio G. Siccardi 《Plasmid》1981,6(1):78-85
Plasmids S-a and Rts1 suppress the galactose-sensitive phenotype of galE mutants of Escherichia coli K-12, giving rise to both galactose-fermenting and nonfermenting strains. Fermenting strains produce normal inducible UDP-galactose epimerase. Plasmids extracted from either a fermenting or a nonfermenting strain are indistinguishable when examined by either measurements of length of relaxed circular molecules by electron microscopy or electrophoretic pattern of restriction endonuclease digestion products. The phenomenon could be explained by reversible recombination between a plasmid-borne epimerase gene and homologous chromosomal sequences. 相似文献
73.
Pasquale Petrilli Pietro Pucci Anna Maria Garzillo Giovanni Sannia Dr. Gennaro Marino 《Molecular and cellular biochemistry》1981,35(2):121-128
Summary Reactivity of sulphydryl groups of cytosolic and mitochondrial aspartate aminotransferases from ox heart has been studied.
A total of 5 and 7 cysteine residues per monomer are present in cAATo and mAATo, respectively. In native conditions only a
single sulphydryl group can be titrated by Nbs2 while the catalytic activity remains unchanged, however in the mitochondrial isozyme the reactivity depends on the functional
state of the enzyme. Reactivity toward NEM reveals the existence of a syncatalytic sulphydryl group in the cytosolic isozyme.
Titration of cAATo with pMB at pH 8 and pH 5 confirms the existence of two exposed sulphydryl groups with a different reactivity.
The results compared with those reported on the corresponding isozymes from pig and chicken heart show that syncatalytic sulphydryl
groups are of general occurrence in these enzymes. 相似文献
74.
75.
Ryszard Farbiszewski Anna Wincewicz Wiktor Rzeczycki 《Molecular and cellular biochemistry》1977,17(1):3-6
Summary Arginine-rich basic protein from cytoplasma of Guerin epitheliomas has been isolated and characterized. It contains five amino acids: arginine, lysine, glycine, alanine and glutamic acid which make together 74 per cent of all amino acid residues. The protein has a cationic character with an isoelectric point of 8.2. No carbohydrate component was found in this protein. The significance of arginine-rich basic protein in the cytoplasma of Guerin epithelioma is discussed briefly. 相似文献
76.
77.
Anna Chrtková 《Folia Geobotanica》1983,18(1):103-105
A new subspecies,Lathyrus nissolia L. subsp.futakii Chrtková subsp. nova is described from East Slovakia. The diacritical characters are: high and rich branched stems, 50–110 cm long and larger, 10–12 mm long, bright orange-red flowers. It differs also in ecology, growing in wet lowland forests with the level of the ground water up to 15 cm over the earth also in summer. 相似文献
78.
Anna Krahulcová 《Folia Geobotanica》1991,26(4):369-377
Chromosome numbers compared with as yet published data are given for the following 12 Phanerogams (both native species and aliens) from Czechoslovakia:Ambrosia trifida L.,Cardamine chelidonia L.,Dephne cneorum L.,Epipactis albensis Nováková etRydlo,Linum flavum L.subsp flavum, Lunaria rediviva L.,Nepeta grandiflora M.BIEB.,Reseda luteola L.,Thlaspi montanum L.,Tithymalus salicifolius (Host)Klotzsch etGarcke,Tithymalus virgultosus (Klokov) Holub andVerbascum speciosum Schrad. subsp.speciosum. The chromosome number 2n=40 is presented for the first time in autogamousEpipactis albensis Nováková etRydlo. New chromosome numbers were found inCardamine chelidonia L. (2n=32) and inTithymalus salicifolius (Host) Klotzch etGarcke (2n=40). Known but less frequent cytotypes are reported inLinum flavum L. subsp.flavum (2n=28) and inVerbascum speciosum Schrad. subsp.speciosum (2n=30). 相似文献
79.
A locus for familial hypertrophic cardiomyopathy is closely linked to the cardiac myosin heavy chain genes, CRI-L436, and CRI-L329 on chromosome 14 at q11-q12 总被引:10,自引:1,他引:9 下载免费PDF全文
Scott D. Solomon Anja A. T. Geisterfer-Lowrance Hans-Peter Vosberg Gudrun Hiller John A. Jarcho Cynthia C. Morton Wesley O. McBride Anna L. Mitchell Allen E. Bale William J. McKenna J. G. Seidman Christine E. Seidman 《American journal of human genetics》1990,47(3):389-394
We report that a gene responsible for familial hypertrophic cardiomyopathy (HC) is closely linked to the cardiac alpha and beta myosin heavy chain (MHC) genes on chromosome 14q11. We have recently shown that probe CRI-L436, derived from the anonymous DNA locus D14S26, detects a polymorphic restriction fragment that segregates with familial HC in affected members of a large Canadian family. Using chromosomal in situ hybridization, we have mapped CRI-L436 to chromosome 14 at q11-q12. Because the cardiac MHC genes also map to this chromosomal band, we have determined the genetic distances between the cardiac beta MHC gene, D14S26, and the familial HC locus. Data presented here show that these three loci are linked within 5 centimorgans on chromosome 14 at q11-q12. The possibility that defects in either the cardiac alpha or beta MHC genes are responsible for familial HC is discussed. 相似文献
80.
Anna Pastuszko 《Neurochemical research》1980,5(7):769-776
The acetylcholinesterase from synaptosomal membranes is inhibited by anesthetics: Nembutal, brietal, and thiopental. Nembutal and brietal decrease theK
m for acetylthiocholine, without changes inV
max. A noncompetitive type of inhibition is produced by thiopental. This anesthetic decreases Arrhenius plot discontinuity by about 4°C and increases activation energies. Nembutal and brietal do not change Arrhenius plot discontinuities, but they increase activation energies. These results suggest that barbiturates change lipid-protein interactions in synaptosomal membranes. 相似文献