TaqI digestion reveals fractions of satellite DNAs on human chromosomes

Genome ◽  
1991 ◽  
Vol 34 (2) ◽  
pp. 251-254 ◽  
Author(s):  
I. Tagarro ◽  
J. J. González-Aguilera ◽  
A. Ma Fernández-Peralta
Keyword(s):  
Restriction Endonuclease ◽  
Human Chromosomes ◽  
Experimental Conditions ◽  
Satellite Dnas ◽  
Final Reaction ◽  
Dna Loss ◽  
Target Sequences ◽  
Main Chromosome ◽  
Taqi Restriction Endonuclease

Restriction endonuclease TaqI has been known as a nonbanding restriction endonuclease when it is used on fixed human chromosomes. However, a specific TaqI digestion can be obtained after varying experimental conditions such as concentration of enzyme, time of incubation, and volume of the final reaction mixture. This digestion consists of an extensive DNA loss in heterochromatin subregions of chromosomes 1, 9, 15, 16, and Y. These regions essentially coincide with those corresponding to the main chromosome locations of satellite II DNA, whose tandem repeated units contain many TaqI target sequences, and some satellite III DNA domains enriched in TaqI sites.Key words: TaqI restriction endonuclease, heterochromatin, satellite DNAs, human chromosomes.

The location of four human satellite DNAs on human chromosomes

1975 ◽  
Vol 14 (3-6) ◽  
pp. 338-339 ◽  
Author(s):  
J.R. Gosden ◽  
A.R. Mitchell ◽  
R.A. Buckland ◽  
R.P. Clayton ◽  
H.J. Evans
Keyword(s):  
Human Chromosomes ◽  
Satellite Dnas

The location of four human satellite DNAs on human chromosomes

1975 ◽  
Vol 92 (1) ◽  
pp. 148-158 ◽  
Author(s):  
J.R. Gosden ◽  
A.R. Mitchell ◽  
R.A. Buckland ◽  
R.P. Clayton ◽  
H.J. Evans
Keyword(s):  
Human Chromosomes ◽  
Satellite Dnas

scholarly journals The EcoRI restriction endonuclease with bacteriophage λ DNA. Kinetic studies

1980 ◽  
Vol 191 (2) ◽  
pp. 581-592 ◽  
Author(s):  
S E Halford ◽  
N P Johnson ◽  
J Grinsted
Keyword(s):  
Restriction Endonuclease ◽  
Protein Interactions ◽  
Dna Sequences ◽  
Individual Recognition ◽  
Kinetic Studies ◽  
Restriction Enzymes ◽  
Reaction Rates ◽  
Recognition Site ◽  
Experimental Conditions ◽  
Ecori Restriction

The kinetics of the reactions of the EcoRI restriction endonuclease at individual recognition sites on the DNA from bacteriophage lambda were found to differ markedly from site to site. Under certain conditions of pH and ionic strength, the rates for the cleavage of the DNA were the same at each recognition site. But under altered experimental conditions, different reaction rates were observed at each recognition site. These results are consistent with a mechanism in which the kinetic stability of the complex between the enzyme and the recognition site on the DNA differs among the sites, due to the effect of interactions between the enzyme and DNA sequences surrounding each recognition site upon the transition state of the reaction. Reactions at individual sites on a DNA molecule containing more than one recognition site were found to be independent of each other, thus excluding the possibility of a processive mechanism for the EcoRI enzyme. The consequences of these observations are discussed with regard to both DNA-protein interactions and to the application of restriction enzymes in the study of the structure of DNA molecules.

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