Long-range organization and sequence-directed curvature of Xenopus laevis satellite 1 DNA.
AUTOR(ES)
Pasero, P
RESUMO
We have investigated the long-range organization and the intrinsic curvature of satellite 1 DNA, an unusual tandemly-repeated DNA family of Xenopus laevis presenting sequence homologies to SINEs. PFGE was used in combination with frequent-cutter restriction enzymes not likely to cut within satellite 1 DNA and revealed that almost all the repeating units are tandemly organized to form large arrays (200 kb to 2 Mb) that are marked by restriction length polymorphism and contain intra-array domains of sequence variation. Besides that, we have analysed the secondary structure of satellite 1 DNA by computer modelling. Theoretical maps of curvature obtained from three independent models of DNA bending (the dinucleotide wedge model of Trifonov, the junction model of Crothers and the model of de Santis) showed that satellite 1 DNA is intrinsically curved and these results were confirmed experimentally by polyacrylamide gel electrophoresis. Moreover, we observed that this bending element is highly conserved among all the members of the satellite 1 DNA family that are accessible to analysis. A potential genetic role for satellite 1 DNA based on this unusual structural feature is discussed.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=331494Documentos Relacionados
- DNA sequence-directed nucleosome reconstitution on 5S RNA genes of Xenopus laevis.
- Calibration of DNA curvature and a unified description of sequence-directed bending.
- Sequence-directed curvature of repetitive AluI DNA in constitutive heterochromatin of Artemia franciscana.
- Biological origins of long-range correlations and compositional variations in DNA.
- Long-range charge hopping in DNA
