Increased temperature and 2-methyl-2,4-pentanediol change the DNA structure of both curved and uncurved adenine/thymine-rich sequences.
Biochemistry
; 42(28): 8587-93, 2003 Jul 22.
Article
em En
| MEDLINE
| ID: mdl-12859206
ABSTRACT
DNA curvature is affected by elevated temperature and dehydrating agents such as 2-methyl-2,4-pentanediol (MPD) (used in crystallization). This effect of MPD has been ascribed to a specific distortion of the structure of adenine tracts (A-tracts), probably through a deformation of the characteristic narrow minor groove. Uranyl photoprobing indicates that a narrowed minor groove is present in all A/T regions containing four or more A/T base pairs. Consequently, this technique may be employed to study conformational changes in other A/T-rich sequences than pure A-tracts. In this study we use uranyl photoprobing to demonstrate that the effect of elevated temperature and MPD is analogous on both "normal" and curve-inducing A/T-rich sequences. The results therefore indicate that under these conditions the minor groove is widened in all A/T sequences and not only in pure A-tracts as previously suggested. Thus, the rather subtle structural difference of AT regions and A-tracts in nonbent DNA versus A-tracts in bent DNA may be quantitative rather than qualitative; i.e., the structure is more persistent and/or rigid in bent DNA.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Plasmídeos
/
DNA
/
Glicóis
/
Conformação de Ácido Nucleico
Tipo de estudo:
Qualitative_research
Idioma:
En
Revista:
Biochemistry
Ano de publicação:
2003
Tipo de documento:
Article
País de afiliação:
Dinamarca