Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

We have studied replication throughout 325 kb of the telomeric region of a human chromosome (16p13.3) and related the findings to various aspects of chromosome structure and function (DNA sequence organization, nuclease-hypersensitive sites, nuclear matrix attachment sites, patterns of methylation and gene expression). The GC-rich isochore lying adjacent to the telomere, which contains the alpha-globin locus and many widely expressed genes, replicates early in the cell cycle regardless of the pattern of gene expression. In subtelomeric DNA, replication occurs later in the cell cycle and the most telomeric region (20 kb) is late replicating. Juxtaposition of early replicating DNA next to the telomere causes it to replicate later in S-phase. Analysis of the timing of replication in chromosomes with deletions, or in transgenes containing various segments of this telomeric region, suggests that there are no critical origins or zones that initiate replication, rather the pattern of replication appears to be related to the underlying chromatin structure which may restrict or facilitate access to multiple, redundant origins. These results contrast with the pattern of replication at the human beta-globin locus and this may similarly reflect the different chromosomal environments containing these gene clusters.

Original publication

DOI

10.1093/hmg/8.8.1373

Type

Journal article

Journal

Hum Mol Genet

Publication Date

08/1999

Volume

8

Pages

1373 - 1386

Keywords

Animals, Cell Line, Transformed, Chromosome Deletion, Chromosomes, Human, Pair 16, DNA, DNA Replication, Gene Expression Regulation, Globins, Humans, Hybrid Cells, In Situ Hybridization, Fluorescence, Mice, Mice, Transgenic, Telomere, Time Factors, Transgenes