Microtubule plus-end-tracking proteins: mechanisms and functions.

Microtubule plus-end-tracking proteins (+TIPs) are a diverse group of molecules that display dynamic accumulation at the distal ends of growing microtubules. Specific binding to the growing microtubule tip coupled with quick detachment from the older lattice, plus-end-directed transport, and association with other +TIPs can all contribute to this protein localisation. +TIPs act mainly as microtubule-stabilising factors and at the same time often link microtubule ends to various cellular structures, such as the cell cortex or kinetochores. Regulation of the activity of +TIPs has profound effects on the shape of the microtubule network and plays an essential role in cell division, motility and morphogenesis.