A guiding torch at the poles: the multiple roles of spindle microtubule-organizing centers during cell division

Abstract

The spindle constitutes the cellular machinery that enables the segregation of the chromosomes during eukaryotic cell division. The microtubules that form this fascinating and complex genome distribution system emanate from specialized structures located at both its poles and known as microtubule-organizing centers (MTOCs). Beyond their structural function, the spindle MTOCs play fundamental roles in cell cycle control, the activation and functionality of the mitotic checkpoints and during cellular aging. This review highlights the pivotal importance of spindle-associated MTOCs in multiple cellular processes and their central role as key regulatory hubs where diverse intracellular signals are integrated and coordinated to ensure the successful completion of cell division and the maintenance of the replicative lifespan.

Keywords: MTOC; aging; centrosome; meiosis; mitosis; spb.

Figure 1.

The multiple roles of microtubule organizing centers in the cell. The spindle pole bodies (SPBs) and centrosomes are the microtubule-organizing centers (MTOCs) that orchestrate spindle formation in yeast and higher eukaryotes, respectively. Besides their structural function, and among others, these fascinating structures also play important roles in (A) the regulation of cell cycle entry and progression, (B) the functionality of the mitotic checkpoints, (C) the interplay between the cell cycle machinery and the nutrient sensing pathways, (D) the differential transport of molecules and organelles and (E) during replicative aging.