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Meiotic proteins Bqt1 and Bqt2 tether telomeres to promote the bouquet arrangement of chromosomes in fission yeast

ABSTRACT: In many organisms, meiotic chromosomes are bundled at their telomeres to form a bouquet arrangement. The bouquet formation plays an important role in homologous chromosome pairing and therefore progression of meiosis. As meiotic telomere clustering occurs in response to mating pheromone signaling in fission yeast, we looked for factors essential for bouquet formation among genes induced under mating pheromone signaling. This genome-wide search identified two novel proteins, Bqt1 and Bqt2, that connect telomeres to the spindle-pole body (SPB; the centrosome equivalent in fungi). Neither Bqt1 nor Bqt2 alone functions as a connector, but together the two proteins form a bridge between Rap1 (a telomere protein) and Sad1 (an SPB protein). Significantly, when both Bqt1 and Bqt2 are ectopically expressed in mitotic cells, they also form a bridge between Rap1 and Sad1. Thus, a complex including Bqt1 and Bqt2 is essential for connecting telomeres to the SPB. Keywords: Keywards: Time course, Nitrogen starvation, Mating pheromone, P-factor.

ORGANISM(S): Schizosaccharomyces pombe

PROVIDER: GSE3515 | GEO | 2006/04/20

SECONDARY ACCESSION(S): PRJNA93561

REPOSITORIES: GEO

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A genetic interaction between RAP1 and telomerase reveals an unanticipated role for RAP1 in telomere protection

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2023-10-22 | PXD031416 | Pride

ZNF524 directly binds telomeres and supports their integrity via TRF2/RAP1

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Aberrant expression and localization of the RAP1 shelterin protein contributes to age-related phenotypes [2019]

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