|
|
MAP code and regulation of microtubule-based processes
Karhanová, Adéla ; Lánský, Zdeněk (advisor) ; Tomášová, Štěpánka (referee)
Microtubule associated proteins (MAPs) are considered as key regulators of molecular trafficking in cells. Even though their malfunctioning results in severe pathologies, such as neurodegenerative disorders, the regulatory roles of these proteins remain under debate. Since MAPs bind to the cytoskeleton, this structure has to be vital for the function of MAPs. Microtubules, a highly dynamic type of cytoskeletal structure, have been given extra attention due to their association with cell division and vital functions in neurons. Microtubules can undergo post-translational modifications that affect molecular motors as well as binding of other proteins, such as MAPs. Whether post-translational modifications of microtubules regulate the distribution of MAPs is so far not sufficiently documented. However, MAPs have been shown to cooperatively form cohesive envelopes on the microtubules and thereby regulate the access of motors and severing enzymes. As there are many types of MAPs and they are mutually exclusive, a hypothesis of a regulatory 'MAP code' emerged recently in the literature. Using available literature, this review will try to introduce the new model of MAP code and provide some background information on previous research on this topic.
|
|
|
Plant tubulin code
Ničová, Klára ; Schwarzerová, Kateřina (advisor) ; Cvrčková, Fatima (referee)
Microtubules, which are made of polymers of α- and β-tubulin, are an integral part of the cytoskeleton. Both types of tubulin share a considerable sequential homology across eukaryotic organisms. Tubulins are encoded by relatively large gene families. The expression of these genes produces different tubulin isotypes, some of which may exhibit different properties. Tubulin isotypes can be further posttranslationally modified. The best known posttranslational modifications of tubulin include acetylation, phosphorylation, tyrosination, polyglutamylation and polyglycylation. The tubulin code arises from the combination of expression of different tubulin isotypes and their posttranslational modifications. As a consequence, microtubules in cells can be composed of a "mixture" of different tubulins with distinct functions and properties. Even though the existence of the tubulin code has been proven in every model organism, plants included, the precise understanding of the meaning of microtubules being composed of different tubulins is still subjected to research. Much of the research on the tubulin code has been carried out on animal models. In contrast, relatively little is known about the existence of the tubulin code in plants. This theses summarizes current knowledge on the localization and regulation...
|
guest ::
