The Telomere Bouquet Controls the Meiotic Spindle

Bouquet formation, in which telomeres gather to a small region of the nuclear membrane in early meiosis, has been observed in diverse eukaryotes, but the function of the bouquet has remained a mystery. Here, we demonstrate that the telomere bouquet plays a crucial role in controlling the behavior of the fission yeast microtubule-organizing center (known as the spindle pole body or SPB) and the meiotic spindle. Using mutations that specifically disrupt the bouquet, we analyze chromosome, SPB, and spindle dynamics throughout meiosis. If the bouquet fails to form, the SPB becomes fragmented at meiosis I, leading to monopolar, multiple, and mislocalized spindles. Correct SPB and spindle behavior require not only the SPB recruitment of telomere proteins but also that the proteins are properly bound to telomeric DNA. This discovery illuminates an unanticipated level of communication between chromosomes and the spindle apparatus that may be widely conserved among eukaryotes.

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