Premium
Repetitive DNA in differntiating chick tissues
Author(s) -
Ayres Kathleen Nelson
Publication year - 1977
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1040930117
Subject(s) - dna , biology , microbiology and biotechnology , dna sequencing , repeated sequence , nucleotide , biochemistry , gene , genome
Embryonic chick DNA from different tissues was examined for diferences in relative content of highly repetitive DNA which might indicate specific DNA amplification in somatic cells. The content of repetitive sequences in DNA isolated from cerebrum, muscle, and neural retina tissues, at the same and at different embryonic stages, was determined by hydroxyapatite fractionation of partially reassociated DNA samples. An unrenatured marker DNA (C 14 ‐labeled E. coli DNA) was added to each chick DNA sample in order to monitor the nonspecific single‐stranded DNA retention by each hydroxyapatite column. When chick DNA samples were sheared to a double‐stranded length of 1,300 nucleotide pairs, an average of 20.2% ± 2.2% of the DNA was found to reassociate at a Cot value of 10. The quantity of the fast reassociating sequences was found to constitute the same fraction of the DNA in all the tissues studied. In addition, all the reassociated DNA samples exhibited the same CsCl density classes. The studies also indicated that most chick DNA repetitive sequences are interspersed with nonrepetitive sequences.