title: DNA sequence organization in the starfish Dermasterias imbricata.
abstract: The sequence arrangement in the genomic DNA of the starfish Dermasterias imbricata has been examined. Analyses of kinetics of reassociation in solution at DNA lengths of 400, 3100, and 6200 base pairs (bp) demonstrate the interspersion of repetitive and unique DNA. At a fragment length of 400 bp, 45% of the DNA reacts at a rate appropriate for single-copy sequences in a genome of this size (0.54 pg). Interspersion of repetitive sequences is also demonstrated by the reduced hyperchromicity of 3100- or 6200-bp fragments reacted to Cot 10, where only repetitive sequences have formed duplex. S1 nuclease digestion of 3100-bp fragments reassociated to Cot 10 shows that both short (approximately 230 bp) and long (greater than or equal to 2600 bp) repetitive sequences are present in this DNA. These data demonstrate a short period interspersion pattern in Dermasterias.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002847:Chromatography, Agarose; D004247:DNA / Q000235:genetics*; D006358:Hot Temperature; D007700:Kinetics; D008297:Male; D009691:Nucleic Acid Denaturation; D013215:Starfish / Q000235:genetics*
chemical_list: D004247:DNA