Fig. 5.

Chromosome organization model in the yeast nucleus. The SPB (rectangle), embedded in the double nuclear envelope (circle), forms a central axis (dotted line) with the centroid (cross) of the nucleolus (gray crescent). Nuclear microtubules (three are shown for simplicity) emanate from the SPB and bind to the centromeric kinetochores (black dots). The length of chromosome arms determines the angular distribution of subtelomeres, with those of smaller arms (<≈300 kb) (light gray) mostly restricted to the vicinity of the SPB (shaded light gray), whereas subtelomeres of longer arms (dark gray) are mostly excluded from this region, extend further away, and are closer to the nucleolus (shaded dark gray).