Sequence-directed curvature of repetitive AluI DNA in constitutive heterochromatin of Artemia franciscana.
An Alu I family of repeated DNA sequence 113 bp in length was found to be the major component of the heterochromatin in Artemia franciscana. On the basis of the analysis of cloned oligomeric (monomer to examer) heterchromatic fragments we predicted that the sequence could produce a stable curvature in chromosomal DNA. This prediction was confirmed by polyacrylamide gel electrophoresis analysis and by electron microscope observations. The anomalous mobility of these fragments is reversed when the DNA samples are electrophoresed in the presence of distamycin A. Moreover treatment of living Artemia with this drug produces visible decondensation of heterochromatic masses in the interphase nuclei.
Benfante
R
R
Dipartimento di Genetica e di Biologia dei Microorganismi, Universitá di Milano, Italy.
Landsberger
N
N
Tubiello
G
G
Badaracco
G
G
D000818:Animals; D001156:Artemia / Q000235:genetics*; D001483:Base Sequence; D004247:DNA / Q000235:genetics / Q000648:ultrastructure*; D015252:Deoxyribonucleases, Type II Site-Specific; D004591:Electrophoresis, Polyacrylamide Gel; D006570:Heterochromatin / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid
D006570:Heterochromatin; D004247:DNA; C024669:endodeoxyribonuclease AluI; D015252:Deoxyribonucleases, Type II Site-Specific