An intrinsically disordered yeast prion arrests the cell cycle by sequestering a spindle pole body component

Electron microscopy of a cryofixed [RNQ+] Rnq1-overexpressing yeast cell containing unduplicated spindle pole bodies (SPBs). The unduplicated SPBs in arrested [RNQ+] cells exhibited a range of abnormal morphologies. The SPBs lacked solid central plaques and often had reduced outer plaques (phenotypes 1 and 2). Some arrested SPBs presented with long half-bridges (phenotype 3) or had a bilobed morphology (phenotype 4 (shown here)).