Highly Conserved Repetitive DNA Sequences are Present at Human Centromeres

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 89; no. 5; pp. 1695 - 1699
• Main Authors: Grady, Deborah L., Ratliff, Robert L., Robinson, Donna L., McCanlies, Erin C., Meyne, Julianne, Moyzis, Robert K.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01.03.1992; National Acad Sciences; National Academy of Sciences
• Subjects: Animals; Artificial satellites; Base Sequence; Biochemistry; Biological and medical sciences; Centromere - ultrastructure; Centromeres; Chromatin. Chromosome; Chromosomes; Cloning, Molecular; Deoxyribonucleic acid; DNA; DNA, Satellite - chemistry; Drosophila; Drosophila melanogaster - genetics; Fundamental and applied biological sciences. Psychology; Heterochromatin - ultrastructure; Hot Temperature; Humans; In situ hybridization; Medical research; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Nucleic Acid Denaturation; Nucleic Acid Hybridization; Nucleotide sequences; Oligodeoxyribonucleotides - chemistry; Oligomers; Repetitive Sequences, Nucleic Acid; Satellite DNA; Yeasts; Human; Molecular evolution; Conserved sequence; Centromere; Nucleotide sequence; Repeated sequence; DNA; Chromosome; Thermal stability
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.89.5.1695

Highly conserved repetitive DNA sequence clones, largely consisting of (GGAAT)nrepeats, have been isolated from a human recombinant repetitive DNA library by high-stringency hybridization with rodent repetitive DNA. This sequence, the predominant repetitive sequence in human satellites II and III, is similar to the essential core DNA of the Saccharomyces cerevisiae centromere, centromere DNA element (CDE) III. In situ hybridization to human telophase and Drosophila polytene chromosomes shows localization of the (GGAAT)nsequence to centromeric regions. Hyperchromicity studies indicate that the (GGAAT)nsequence exhibits unusual hydrogen bonding properties. The purine-rich strand alone has the same thermal stability as the duplex. Hyperchromicity studies of synthetic DNA variants indicate that all sequences with the composition (AATGN)nexhibit this unusual thermal stability. DNA-mobility-shift assays indicate that specific HeLa-cell nuclear proteins recognize this sequence with a relative affinity >105. The extreme evolutionary conservation of this DNA sequence, its centromeric location, its unusual hydrogen bonding properties, its high affinity for specific nuclear proteins, and its similarity to functional centromeres isolated from yeast suggest that this sequence may be a component of the functional human centromere.