Molecular structure of a complete turn of A-DNA.
We have determined the crystal structure of the dodecamer d(CCCCCGCGGGGG), showing for the first time a complete turn of A-DNA. It has average structural parameters similar to those determined in fibres. Nevertheless it shows a considerable local variation in structure which is in part associated with the presence of a bound spermine molecule. We conclude that the local DNA conformation does not only depend on the base sequence, but may be strongly modified upon interaction with other molecules. In particular, the CpG sequence, which is found in hypersensitive regions of the genome, appears to be able to easily change its conformation under external influences.
Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Barcelona, Spain.
N
N
Verdaguer
J
J
Aymami
D
D
Fernández-Forner
I
I
Fita
M
M
Coll
T
T
Huynh-Dinh
J
J
Igolen
J A
JA
Subirana
D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D015226:Dinucleoside Phosphates / Q000737:chemistry; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D013096:Spermine / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D015226:Dinucleoside Phosphates; D014867:Water; D013096:Spermine; D004247:DNA