Plasma membrane (PM) and mitochondrial membrane (MM) proteins of rat hippocampal neurons were identified and comparatively characterized on the basis of a sequential digestion-centered combinative strategy for sample treatment. A total of 478 membrane proteins were identified, of which 240 had PM localization, 170 had MM localization, and 33 had both of the two subcellular localizations. Compared with the PM proteome, the MM proteome not only was smaller, more basic, and more hydrophobic, but also had a narrower protein molecular mass distribution range and a higher proportion of transmembrane proteins. By functional enrichment analysis, 287 molecular function terms for the PM proteome and 173 for the MM proteome were obtained. The MM proteome had a lower percentage of binding function terms and a higher percentage of catalysis function terms than the PM proteome, suggesting that mitochondrial proteins were more inclined to affect the physiological and biochemical processes by binding various molecules and as enzymes. Biological process enrichment showed that the genes of the PM and MM proteomes were mapped to 1104 and 460 biological processes, respectively. The biological processes with the most mapped genes of the PM proteome included those involved in vesicle recycling, transmitter release, neuronal development, protein and ion transport, etc., whereas those involved in electron transport, ATP synthesis, mitochondrial transport, mitochondrial apoptosis, etc., were the most gene-mapped biological processes for the MM proteome. The present work has deepened our understanding of the structure and function of hippocampal neurons and provided reference methods for research in the related field.

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识别和比较海马神经元的质膜（PM）和线粒体膜（MM）蛋白的基础上，以顺序消化为中心的组合策略进行样品处理。总共鉴定出478个膜蛋白，其中240个具有PM定位，170个具有MM定位，并且33个具有两个亚细胞定位。与PM蛋白质组相比，MM蛋白质组不仅更小，更碱性，更疏水，而且具有更窄的蛋白质分子量分布范围和更高的跨膜蛋白质比例。通过功能富集分析，获得了PM蛋白组的287个分子功能项和MM蛋白组的173个分子功能项。与PM蛋白质组相比，MM蛋白质组具有较低的结合功能项百分比和较高的催化功能项百分比，表明线粒体蛋白更倾向于通过结合各种分子和作为酶来影响生理和生化过程。生物过程富集表明，PM和MM蛋白质组的基因分别定位于1104和460个生物过程。PM蛋白质组中基因图谱最多的生物过程包括那些参与小泡循环，递质释放，神经元发育，蛋白质和离子运输等的过程，而那些涉及电子运输，ATP合成，线粒体运输，线粒体凋亡等的过程。 ，是MM蛋白质组中基因最多的生物学过程。

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