Characterization of Atg18p and its role in cellular trafficking in Saccharomyces. cerevisiae.

Khaliq, Samira (2013). Characterization of Atg18p and its role in cellular trafficking in Saccharomyces. cerevisiae. University of Birmingham. Ph.D.

Preview

Khaliq13PhD.pdf
PDF - Accepted Version
Download (17MB)

Abstract

Ptdins3P and PtdIns(3,5)P2 are phosphoinositides which act as signaling lipids in eukaryotic cells, mediating trafficking through spatio-temporal regulation of effector proteins. Atg18p, a yeast PROPPIN, binds PtdIns3P and PtdIns(3,5)P2 and this study focuses on characterization of Atg18p in order to gain insight into its functions. In vivo localization of GFP-Atg18p under various conditions indicates that the localization of Atg18p is under dual control of lipid binding as well as protein interactions, especially Vac7p. In vivo investigations of Atg18p mutants (in the highly conserved lipid binding domain) indicate that Atg18p lipid binding is slightly distinct from K. lactis Hsv2p lipid binding. In addition, Fourier transform ion cyclotron resonance mass spectrometry data indicates that Atg18p-lipid binding could be affected through possible modifications. The experiments carried out in this research also show that Atg18p binds Vps41p and Apl5p independently, through particular sites which overlap its lipid binding domain and hence offers a plausible explanation for in vivo localization of Atg18p during various processes e.g salt stress and autophagy.

Type of Work:

Thesis (Doctorates > Ph.D.)

Award Type:

Doctorates > Ph.D.

Supervisor(s):