Centromeres from telomeres? The centromeric region of the Y chromosome of Drosophila melanogaster contains a tandem array of telomeric HeT-A- and TART-related sequences.
نویسندگان
چکیده
Cytological and cytogenetic studies have previously defined the region needed for centromeric function in the Y chromosome of Drosophila melanogaster. We have identified a YAC clone that originated from this region. Molecular analysis of the YAC and genomic DNAs has allowed the description of a satellite DNA made of telomeric HeT-A- and TART-derived sequences and the construction of a long-range physical map of the heterochromatic region h18. Sequences within the YAC clone are conserved in the centromeric region of the sibling species Drosophila simulans. That telomere-derived DNA now forms part of the centromeric region of the Y chromosome could indicate a telomeric origin of this centromere. The existence of common determinants for the function of both centromeres and telomeres is discussed.
منابع مشابه
The Y chromosome of Drosophila melanogaster contains a distinctive subclass of Het-A-related repeats.
The HeT-A element is a transposable element with an apparent role in the structure of the telomeres of Drosophila melanogaster chromosomes. HeT-A transposition is the earliest event detected in healing of broken ends; HeT-A is also found on telomeres of unbroken chromosomes. Sequences with homology to HeT-A are never detected in euchromatic regions; however, clusters of HeT-A-related sequences ...
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عنوان ژورنال:
- Nucleic acids research
دوره 27 16 شماره
صفحات -
تاریخ انتشار 1999