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

Cytological and cytogenetic studies have previously defined the region need ed 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 sate llite DNA made of telomeric HeT-A- and TART-derived sequences and the const ruction of a long-range physical map of the heterochromatic region h18. Seq uences within the YAC clone are conserved in the centromeric region of the sibling species Drosophila simulans. That telomere-derived DNA now forms pa rt of the centromeric region of the Y chromosome could indicate a telomeric origin of this centromere, The existence of common determinants for the fu nction of both centromeres and telomeres is discussed.