|
|
Tubulin post-translational modifications and microtubule associated proteins in neural development and disease.
Belyaeva, Polina ; Balaštík, Martin (advisor) ; Siahaan, Valerie (referee)
Microtubules (MTs) are essential components of the cytoskeleton in all eukaryotic cells. Their function is particularly important in neurons where MTs stabilize their long processes and are responsible for the precisely regulated anterograde and retrograde, intra-axonal and intra- dendritic transport over long distances. MTs are essential also during development of the vertebrate brain and all its major steps: neurogenesis, neuronal migration and neuronal differentiation. MTs are regulated at multiple levels, but two seem to be particularly important: 1. posttranslational modifications of tubulin (PTMs) have been shown to control several MT properties as stability or MT-based transport. 2. microtubule-associated proteins (MAPs) that bind soluble MT subunits, MT lattice as well as MT ends and control MT-based transport and MT dynamics by either stabilizing, destabilizing or severing MTs. Consequently, deregulation of either tubulin PTMs or MAPs may induce severe changes in neuronal cytoskeleton. Bachelor's thesis summarizes current knowledge on how PTMs (especially polyglutamylation) and MAPs (especially microtubule cleaving proteins such as spastin) regulate MT and neuronal development and degeneration. Keywords: Microtubules, tubulin post-translational modifications, polyglutamylation,...
|
|
|
The role of microtubules splitting proteins in regulation of cytoskeleton.
Uhlířová, Jana ; Dráber, Pavel (advisor) ; Libusová, Lenka (referee)
Microtubules are highly dynamic cytoskeletal structures, which secure cell shape, intracellular transport and organization of cellular organelles. They also participate in cell migration and in formation of mitotic spindle. Microtubules create a highly organized network which changes its organisation in response to the immediate need of the cell. They are formed of αβ-tubulin dimers and a large number of associated proteins. Microtubules are a polar structures with (+) and (-) ends, that differ in the rate of assembly. For fast regulation of microtubule structure are important microtubule-severing proteins (spastin, katanin and fidgetin), that belong to the AAA ATPases. These proteins associate with microtubules and consequently sever microtubules into two parts creating new (+) and (-) ends. In this way, they regulate many cellular processes, such as maintaining of cell shape, cell motility, proliferation and differentiation. Beside microtubule-severing activity, spastin and fidgetin are involved in processes in cell nucleus. Spastin is also associated with membranes and participates in modulation of endoplasmic reticulum and generation of endosomal vesicles. Mutations of microtubule-severing proteins cause embryonal development disorders, nervous system defects or infertility. The latest research...
|
guest ::
