Medicine and Health Sciences Commons^™

The Noncanonical Roles Of Two Primordial Molecules In Flagella, Xiaoyan Zhu

Dissertations (1934 -)

Motile cilia and flagella are ancient organelles that eukaryotic organisms today still rely on to thrive in their natural environment. Not surprisingly, accumulated evidence has shown that the intricate motility machinery, the microtubule-based axoneme, is evolutionarily conserved down to the molecular level. This notion is epitomized by the signature axonemal complex, the radial spoke (RS). The RS is part of a control center conferring the high frequency and tightly regulated movement. Key RS proteins discovered in biflagellate green alga, Chlamydomonas reinhardtii, are also generated by nearly all ciliated organisms, including Homo sapiens. Among them are two subunits from primordial protein …

Mechanisms Of Neuronal Death Induced By Environmental Toxicants In Murine Cortical Culture, Travis Rush

Dissertations (1934 -)

This study was directed at examining the neurotoxic mechanisms of several classes of environmental toxicants implicated in neurodegenerative disease. Primary cortical cultures were exposed to organophosphorus pesticides, heavy metals and the cyanobacterial toxin, beta-N-methylamino-L-alanine (BMAA). Several components relating to neuronal injury were assessed in each study and novel aspects are described.

The main action of organophosphorous insecticides is generally believed to be the inhibition of acetylcholinesterase. However, these compounds are now recognized to inhibit many other enzymes and cause neuronal death through a variety of mechanisms. I found that exposure to chlorpyrifos or diazinon caused concentration-dependent neurotoxicity that could not …