Functional Analysis of an Integrated GTPase Regulating the Cellular Pool and Distribution Profile of Intraflagellar Transport Particles in Chlamydomonas Reinhardtii
MetadataShow full item record
Cilia and flagella are sensory organelles, found in the majority of eukaryotic organisms that play a vital role in the general physiology, health and early development of humans. Intraflagellar transport (IFT) is tasked with building and maintaining the entire ciliary structure by facilitating the transport of axonemal precursors, trafficking of ciliary membrane proteins and turnover products. Currently, there are no complete models detailing how ciliated organisms regulate the entry and exit of IFT particles, a multi-meric adaptor complex that ferries flagellar proteins. In this thesis, I focus on small Rab-like protein IFT22, an IFT-particle integrated protein with predicted GTPase activity, as a potential regulatory component of IFT particle trafficking in Chlamydomonas. Using an artificial microRNAs strategy, I show that IFT22 regulates the available cellular pool of IFT particles and the distribution profile of the IFT particles between the cytoplasm and the flagellar compartment. Additionally, I demonstrate how the putative constitutive active mutant of IFT22 is able properly localize to the peri-basal body and enter the flagellar compartment using immunofluorescence and immunoblot analysis of flagella extracts. Finally, preliminary RNAi data suggests IFT25 the IFT particle/motor/BBSome assembly downstream of IFT22 regulation, evident from the depletion of kinesin-2 subunit FLA10, IFT-dynein-2 subunit D1bLIC and BBsome component BBS3from whole cell extracts of IFT25 knockdown transformants.
Silva, David (2012). Functional Analysis of an Integrated GTPase Regulating the Cellular Pool and Distribution Profile of Intraflagellar Transport Particles in Chlamydomonas Reinhardtii. Master's thesis, Texas A&M University. Available electronically from