Novel structure at 5'-ends of nascent DNA chains.

AUTOR(ES)
RESUMO

Because of their association with protein short nascent DNA chains in Escherichia coli can be separated from other cellular DNA by chromatography on hydroxylapatite. Protein-free DNA chains of less than 500 nucleotides in length are resistant to degradation from the 5'-end by alkaline phosphatase [orthophosphoric-monoester phosphohydrolase (alkaline optimum); EC 3.1.3.1] and spleen phosphodiesterase (oligonucleate 3'-nucleotidohydrolase; EC 3.1.4.18). In contrast, DNA chains containing more than 500 nucleotides are degradable. From these results we conclude that short nascent DNA chains are structurally modified at their 5'-ends. The nature of this structure and its possible functions are discussed.

Documentos Relacionados