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Dynamin-like protein including dynamins, mitofusins, and guanylate-binding proteins The dynamin family of large mechanochemical GTPases includes the classical dynamins and dynamin-like proteins (DLPs) that are found throughout the Eukarya. This family also includes bacterial DLPs. These proteins catalyze membrane fission during clathrin-mediated endocytosis. Dynamin consists of five domains; an N-terminal G domain that binds and hydrolyzes GTP, a middle domain (MD) involved in self-assembly and oligomerization, a pleckstrin homology (PH) domain responsible for interactions with the plasma membrane, GED, which is also involved in self-assembly, and a proline arginine rich domain (PRD) that interacts with SH3 domains on accessory proteins. To date, three vertebrate dynamin genes have been identified; dynamin 1, which is brain specific, mediates uptake of synaptic vesicles in presynaptic terminals; dynamin-2 is expressed ubiquitously and similarly participates in membrane fission; mutations in the MD, PH and GED domains of dynamin 2 have been linked to human diseases such as Charcot-Marie-Tooth peripheral neuropathy and rare forms of centronuclear myopathy. Dynamin 3 participates in megakaryocyte progenitor amplification, and is also involved in cytoplasmic enlargement and the formation of the demarcation membrane system. This family also includes mitofusins (MFN1 and MFN2 in mammals) that are involved in mitochondrial fusion. Dynamin oligomerizes into helical structures around the neck of budding vesicles in a GTP hydrolysis-dependent manner.
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