Methylation sensitivity of restriction enzymes interacting with GATC sites.
نویسندگان
چکیده
924 BioTechniques Vol. 34, No. 5 (2003) inates the residual ribonuclease activity, although the effect of this treatment on the subsequent experiments should be checked. An inhibitor of RNase, such as Rnasin, can also be added to further enzymatic reactions. This study has described a degrading activity in RNA preparations from ovine, bovine, and porcine brain and ovine liver. Further experiments on these species need to be undertaken to verify whether the ribonuclease activity is present in other tissues or not. RNA extracted according to protocols other than those of Chomczynski and Sacchi should also be tested in artiodactyls as well as in species from other orders.
منابع مشابه
Studies on the biological role of dna methylation; IV. Mode of methylation of DNA in E. coli cells.
Two pairs of restriction enzyme isoschizomers were used to study in vivo methylation of E. coli and extrachromosomal DNA. By use of the restriction enzymes MboI (which cleaves only the unmethylated GATC sequence) and its isoschizomer Sau3A (indifferent to methylated adenine at this sequence), we found that all the GATC sites in E. coli and in extrachromosomal DNAs are symmetrically methylated o...
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ورودعنوان ژورنال:
- BioTechniques
دوره 34 5 شماره
صفحات -
تاریخ انتشار 2003