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Prefoldin is critical for meiotic spindle function, revealing coupling between chromosome segregation and cellular remodeling

ABSTRACT: Faithful chromosome segregation is essential for producing viable gametes via meiosis which is often described as a specialized version of mitotic segregation. The key specializations known include the addition of that allow two sequential segregation events with no intervening round of DNA segregation. Here, in contrast, we identify the ubiquitously expressed prefoldin subunit Gim3 as a critical regulator of meiotic but not mitotic chromosome segregation. Loss of Gim3 causes pronounced chromosome mis-segregation and reduced spore viability through reduced tubulin protein levels and compromised spindle elongation. GIM3 deletion minimally affects spindle length and chromosome segregation in mitosis, despite similar tubulin levels in both cases, highlighting a previously unrecognized difference between meiotic and mitotic spindles. Beyond chromosome segregation, gim3Δ cells exhibit defects in meiotic cellular remodeling, including increased inheritance of cytosolic aggregates into newly forming spores. Importantly, experimentally induced chromosome mis-segregation disturb cellular remodeling, indicating that chromosome segregation and chromatin-directed remodeling are mechanistically linked processes. Together, our findings establish Gim3 as a key factor for both chromosome segregation integrity and cellular remodeling in meiosis, and reveal a previously unrecognized coupling between these processes.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE314037 | GEO | 2026/08/13

REPOSITORIES: GEO

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