Impact of the 'tubulin economy' on the formation and function of the microtubule cytoskeleton

The microtubule cytoskeleton is assembled from a finite pool of alpha,beta-tubulin, the size of which is controlled by an autoregulation mechanism. Cells also tightly regulate the architecture and dynamic behavior of microtubule arrays. Here, we discuss progress in our understanding of how tubulin autoregulation is achieved and highlight work showing that tubulin, in its unassembled state, is relevant for regulating the formation and organization of microtubules. Emerging evidence suggests that tubulin regulates microtubule-associated proteins and kinesin motors that are critical for microtubule nucleation, dynamics, and function. These relationships create feedback loops that connect the tubulin assembly cycle to the organization and dynamics of microtubule networks. We term this concept the 'tubulin economy', which emphasizes the idea that tubulin is a resource that can be deployed for the immediate purpose of creating polymers, or alternatively as a signaling molecule that has more far-reaching consequences for the organization of microtubule arrays.

Automated summary

The microtubule cytoskeleton is assembled from a finite pool of alpha, beta-tubulin controlled by autoregulation. Tubulin in its unassembled state plays a crucial role in regulating the formation and organization of microtubules. Tubulin also regulates microtubule-associated proteins and kinesin motors, forming feedback loops that connect the tubulin assembly cycle to the organization and dynamics of microtubule networks in a concept known as the 'tubulin economy'.