Comparison of Differential Proteins in Normal and Memory-deficient Drosophila melanogaster

正常果蠅及突變果蠅之差異性蛋白分析

李曉芸(Hsiao-Yun Li)

指導教授 ： 呂平江

國立清華大學/生命科學院/生物資訊與結構生物研究所/碩士(2010年)

摘要

Learning and memory are not unitary processes. They are extremely complicated and dynamic. Proteins participate in memory formation are tightly regulated by various pathways, and may require protein synthesis and/or post-translational modifications. A memory-related gene (Amnesiac) in Drosophila melanogaster, encodes a neuropeptide which takes part in the memory-related protein kinase A (PKA) activity. Flies with mutated amn possess normal learning and memory behavior within the first 30 minutes of training. However, the process by which that learned can not be retained after 30 minutes of training, indicating these mutants are with deficits in middle-term memory (MTM). Using 2D-DIGE, we compared the protein expression pattern of D. melanogaster wild-type strains (2u, Canton-Special) with memory-deficient mutant (AmnX8). The results of this work provide new insights into understanding of protein expression level during memory formation. Protein spots with different expression levels between wild type and memory-deficient mutants were selected and identified. We identified 30 proteins that are differentially expressed between 2u and AmnX8 in fly brain. Protein 14-3-3 is more abundant in 2u than AmnX8 (9.26-fold). Recent studies indicate that 14-3-3 protein plays an indispensable role in the memory formation. In addition, energy-related proteins, cytoskeleton proteins and iron-related proteins are down-regulated in the mutant strain. Glycerol-3-phosphate dehydrogenase is shown to be post-translationally modified. As a result, glycerol-3-phosphate dehydrogenase plays in learning and memory formation is an alluring theme for future studies.
Eph family is the largest family of receptor tyrosine kinase, which is comprised of 16 receptors and 9 ligands. Eph receptor tyrosine kinase is a single transmembrane protein which is located on post-synaptic neurons, and its molecular weight is 121.5 kDa. Previous studies revealed that after Eph receptor tyrosine kinase interacts with NMDA receptor, calcium ions influx into postsynaptic neuron, causing alterations in synaptic plasticity. Hence, in this study we overexpressed and purified the Drosophila ephrin receptor tyrosine kinase (Dek) in E. coli and generated an antibody that recognizes the carboxyl terminal of Dek. The anti-Dek-C antibody was employed to examine the direct interaction between NMDA and Eph receptors in Drosophila brain.

關鍵字

果蠅 ； 記憶 ； 二維電泳

並列摘要

無資料

並列關鍵字

Drosophila melanogaster ； Memory ； Ephrin receptor ； Dek ； 2D-DIGE

參考文獻

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