BLOCK IN ANAPHASE CHROMOSOME SEPARATION CAUSED BY A TELOMERASE TEMPLATE MUTATION

Telomeres are essential for chromosome stability, but their functions at specific cell-cycle stages are unknown. Telomeres are now shown to have a role in chromosome separation during mitosis. In telomeric DNA mutants of Tetrahymena thermophila, created by expression of a telomer ase RNA with an altered template sequence, division of the germline nu cleus was severely delayed or blocked in anaphase, The mutant chromati ds failed to separate completely at the midzone, becoming stretched io up to twice their normal length. These results suggest a physical blo ck in mutant telomere separation.