COBRE: UND: ALPHA-SYNUCLEIN IN BRAIN LIPID METABOLISM

点击翻译按钮获取中文摘要

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Elucidating the physiological function of alpha-synuclein is important because mutations in this protein are implicated as a causative factor in familial Parkinson disease (PD) and because alpha-synuclein is associated with a number of other neurodegenerative diseases. Preliminary data contained herein indicates that alpha-synuclein dramatically affects steady-state lipid mass in brain and in isolated synaptosomes, suggesting that alpha-synuclein has a significant impact on brain phospholipid metabolism. Collectively, these changes, along with others, could alter the basal biophysical state of the membrane as well as decrease intracellular second messenger generation via a reduction in lipid-mediated signaling. Thus, it is critical to address the mechanism(s) by which alpha-synuclein affects brain lipid metabolism to gain a greater understanding regarding the potential physiological role for alpha-synuclein in the brain. The following specific aims are designed to address the impact that alpha-synuclein has on brain phospholipid metabolism using a combination of whole animal, cell culture, and in vitro approaches. Aim 1. Determine the effect of alpha-synuclein on brain phospholipid metabolism in vivo using steady-state radiotracer kinetics to assess the kinetics of phospholipid biosynthesis and downstream processing in alpha-synuclein gene-abated and control mice. Aim 2. Determine the effect of alpha-synuclein on cellular phospholipid metabolism ex vivo using stable isotopes and radiotracers to assess the kinetics of phospholipid biosynthesis and downstream processing in neurons and glia isolated from alpha-synuclein gene-abated and control mice. Aim 3. Compare the effects of mutant and wild-type alpha-synuclein on phospholipid metabolism in stably transfected HEK-293 cells using stable isotopes and radiotracers to assess the kinetics of phospholipid biosynthesis and downstream processing. Aim 4. Determine the ability of wild-type and mutant alpha-synuclein to directly alter phospholipid biosynthesis in vitro using a combination of approaches. We will test the hypothesis that alpha-synuclein stimulates phospholipid synthesis through a direct stimulation of phosphatidic acid biosynthesis, thereby increasing the phosphatidic acid pool available for use in downstream synthesis of specific phospholipids.