Show simple item record

dc.contributor.authorRöthlisberger, Sarah Ruth
dc.date.accessioned2018-09-11T21:28:40Z
dc.date.available2018-09-11T21:28:40Z
dc.date.issued2008
dc.identifier.urihttp://hdl.handle.net/10179/13790
dc.description.abstractDynamins are GTPases concerned with membrane tubulation and scission (Praefcke and McMahon, 2004). In the fission yeast, Schizosaccharomyces pombe, the dynamin-related proteins (DRPs) Vps1 and Dnm1 act redundantly in peroxisome biogenesis (Jourdain et al., 2008) but nothing is known about their other cellular roles. Fission yeast cells contain ~20 small, spherical vacuoles that undergo fission or fusion in response to environmental signals (Bone et al., 1998). S. pombe cells lacking Vps1 had smaller vacuoles with reduced capacity for fusion in response to hypotonic stress but enhanced fission in response to hypertonic conditions. Unlike wild type, vps1Δ vacuoles showed no change in diameter in response to temperature stress. Vps1-Cgfp localised to the vacuolar membrane both in living cells and in isolated vacuoles. vps1Δ cells showed close to wild type levels of vacuole protein processing and normal actin organisation and endocytosis. Overexpression of Vps1 caused a global transformation of vacuoles from spherical to tubular. Spherical vacuoles were restored by repression of vps1 expression or by induction of vacuole fusion. Tubulation was blocked in the presence of GTPγS and in a vps1 mutant that lacked the entire GTPase domain. Vacuole tubulation was more extensive in the absence of a second DRP, Dnm1. The absence of Dnm1 abolished the hyper fission phenotype of vps1Δ, whereas overexpression of Dnm1 induced vacuole fission. These results are consistent with a model of vacuole fission in which Vps1 creates a tubule of an appropriate diameter for subsequent scission by another DRP. Preliminary evidence suggests that Dnm1 serves the latter role.en_US
dc.language.isoenen_US
dc.publisherMassey Universityen_US
dc.rightsThe Authoren_US
dc.subjectSchizosaccharomyces pombeen_US
dc.subjectMembrane proteinsen_US
dc.subjectGuanosine triphosphataseen_US
dc.titleThe role of dynamin-related proteins in vacuole biogenesis in fission yeast (Schizosaccharomyces pombe) : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Palmerston North, New Zealanden_US
dc.typeThesisen_US
thesis.degree.disciplineBiochemistryen_US
thesis.degree.grantorMassey Universityen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M. Sc.)en_US


Files in this item

Icon
Icon

This item appears in the following Collection(s)

Show simple item record