رسالة جامعية

Characterization of synapsins SUMOylation

التفاصيل البيبلوغرافية
العنوان: Characterization of synapsins SUMOylation
المؤلفون: Tang, Leo Tsz-Ho
بيانات النشر: University of Bristol, 2014.
سنة النشر: 2014
المجموعة: Ethos UK
مصطلحات موضوعية: 572
الوصف: Synapsins are neuron-specific phosphoproteins that are key components of the presynaptic neurotransmitter release machinery. Their main role is to cluster synaptic vesicles (SVs) to each other and anchor them to the actin cytoskeleton, thereby establishing the reserve vesicle pool, and then release them in response to appropriate membrane depolarisation. Here we demonstrate that, in addition to phosphorylation, SUMOylation of Synapsin la (Synla) at K687R is necessary for Synla function. SUMOylation refers to the covalent attachment of a small protein SUMO onto one of its lysine residue. The attachment of SUMO in turn causes changes in the behavior of the protein. Fluorophore-based exocytosis assay showed that replacement of endogenous Synla in neurons with a non-SUMOylatable mutant impairs stimulated SV exocytosis, primarily through a change in size of the releasable vesicle pool. Through SV binding assay and Synla dispersion assay, we found that SUMOylation enhances Synla association with SVs to promote efficient reclustering of Synla following neuronal stimulation. Co-localization assays also showed that SUMOylation aids in Synla targeting to the presynaptic terminal. Finally, the A548T mutation in Synla is strongly associated with autism spectrum disease (ASD) and epilepsy and we identify that A548T causes defective Synla SUMOylation. We further demonstrate the similar phenotype displayed by the non-SUMOylatable mutant and the A548T mutant. These results identify SUMOylation as a fundamental regulator of Synla function and reveal a novel link between reduced SUMOylation of Synla and neurological disorders.
Original Identifier: oai:ethos.bl.uk:683562
نوع الوثيقة: Electronic Thesis or Dissertation
الإتاحة: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683562Test
رقم الانضمام: edsndl.bl.uk.oai.ethos.bl.uk.683562
قاعدة البيانات: Networked Digital Library of Theses & Dissertations