SARs, ARSs, and A,T-rich regions evidenced by restriction mapping on an 835-kb DNA fragment from Drosophila.
In Drosophila, sequences anchoring the DNA molecule to the scaffold (SARs) and sequences able to replicate autonomously (ARSs) had been shown to comap on an 835-kb DNA fragment (Brun et al. (1990) Mol. Cell. Biol. 10, 5455-5463). To investigate the question of whether this comapping results from the coincidental recruitment of SARs and ARSs in A,T-rich regions, A,T-rich regions of the 835-kb DNA fragment have been identified by restriction analysis with enzymes recognizing motifs made exclusively of A and T. Within the limits of sensitivity of this approach, the obtained data favor the idea of a noncoincidental recruitment: obviously a SAR and an ARS subpopulation are preferentially localized in the A,T-rich regions, but not every A,T-rich region displays a SAR activity, or an ARS activity, or both, nor are all SARs or ARSs localized in the A,T-rich regions. In addition, the data support the idea that a statistical assessment of base composition using restriction analysis might be developed into a general useful approach to genome organization.
Brun
C
C
Laboratoire de Génétique et Physiologie du Développement, Parc Scientifique de Luminy, Marseille, France.
Jullien
N
N
Jacobzone
M
M
Gautier
C
C
Miassod
R
R
D000225:Adenine / Q000032:analysis; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D004261:DNA Replication; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004330:Drosophila / Q000235:genetics*; D016678:Genome; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D013379:Substrate Specificity; D013941:Thymine / Q000032:analysis
D004247:DNA; D004262:DNA Restriction Enzymes; D000225:Adenine; D013941:Thymine