#Regulation of cytoskeleton dynamics and cell division - 季哲剑教授课题组

Microtubules, together with microfilaments and intermediate filaments, form the cell cytoskeleton. They are important for vesicle trafficking, cell division, and cell migration. Although the dynamics of microtubules is mainly mediated by the addition and removal of tubulin dimers at the plus and minus ends, a group of AAA ATPases – including Spastin, the Katanin family, and the Fidgetin family – can break a microtubule into two by severing at a middle point of the tubule. The severing of microtubules is crucial at the end of mitosis, when dissolution of the microtubules spanning two daughter cells is needed to allow separation of the daughter cells. These microtubule severing enzymes are specific-type ATPases, only processing alpha- and beta-tubulin molecules. But it remains not fully understood how these ATPases recognize or process tubulin molecules. In addition, mutations in the human Spastin gene can cause hereditary spastic paraplegia, a type of neurodegenerative disorders. The underlying molecular mechanism is largely unknown. Our lab aims to understand the roles of these microtubule severing enzymes both in normal cells and in disease cells.