Type
Text
Type
Thesis
Date
2007-12-01
Keywords
Candida albicans | Gpr1 | multimorphic organisms
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/70835
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
Candida albicans is an opportunistic fungal pathogen in humans. It typically lives as a harmless commensal as part of the human gut and skin flora, but under some conditions it causes mucosal infections. In immunocompromised patients it can also cause lifethreatening systemic infections. C. albicans is a multimorphic organism, and the ability to undergo morphological transition from budding to hyphal growth is associated with its virulence. This morphological switch was reported to be regulated by different signaling pathways. One key pathway is cAMP-PKA signaling pathway. The single adenylyl cyclase in C. albicans is CaCdc35, which was reported to interact with plasma membrane associated protein Ras1. However, the localization of CaCdc35 remains unclear. We proposed that adenylyl cyclase is plasma membrane associated. The GFP tagging technique was used to study the spatial localization of the adenylyl cyclase CaCdc35. Bacterial expression of CaCdc35 and protein purification were performed for further study of this protein. G protein-coupled receptor Gpr1 is an important plasma membrane iv sensor in C. albicans and the deletion of GPR1 produces defects in hyphal formation and morphogenesis in C. albicans. Gpr1 interacts with Gα protein Gpa2 and activates the cAMP signaling pathway. However, the nature of the ligand for Gpr1 is still unclear. Previous studies pointed to the possibility that amino acids are ligands of Gpr1. Thus, GFP tagging technique was used to visualize the protein on plasma membrane. Internalization experiment was performed to test the possibility that methionine is the ligand of Gpr1. Technique problems appeared to limit the conclusions. Future perspectives were brought up for solving the problems and exploring new topics in the study of C. albicans.
Recommended Citation
Zhang, Qiao, "Regulation of Fungal Morphogenesis" (2007). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 53.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/53