Sphingomyelin (SM) is a major sphingolipid in mammalian cells whereas its analog, ceramide phosphoethanolamine (CPE) is found in trace amounts in mammalian cells and in larger amounts in invertebrates such as insect cells like Drosophila melanogaster. To visualize endogenous SM or CPE, we need specific probes able to recognize the chemical structure of the lipid, rather than its physical property. A limited number of proteins is known to specifically and strongly bind SM or CPE. These proteins are either toxins produced by non-mammalian organisms, subunits or fragments of toxins or a protein that has similar structure to a toxin. These proteins labeled with small fluorophore (e.g. Alexa Fluor) or conjugated to fluorescent proteins (e.g. mCherry) or other types of markers (e.g. ¹²⁵I, maltose-binding protein) are used to detect SM or CPE. Here we summarize the characteristics of specific SM-binding proteins, lysenin and equinatoxin II; CPE- and SM/cholesterol (Chol) binding aegerolysin proteins, pleurotolysin A₂, ostreolysin and erylysin A and SM/Chol-binding protein, nakanori. Then we give examples of their applications including their limitations related not only to their lipid specificity and binding constants, but also to the lipid organization in the membrane.

鞘磷脂（SM）是哺乳动物细胞中的主要鞘脂，而其类似物神经酰胺磷酸乙醇胺（CPE）在哺乳动物细胞中存在痕量，而在无脊椎动物如昆虫果蝇（Drosophila melanogaster）等无脊椎动物中则发现较多。为了可视化内源性SM或CPE，我们需要能够识别脂质的化学结构而不是其物理性质的特定探针。已知有限数量的蛋白质可以特异性和牢固地结合SM或CPE。这些蛋白质或者是由非哺乳动物生物体产生的毒素，毒素的亚基或片段，或者是具有与毒素相似结构的蛋白质。这些蛋白用小荧光团标记（例如Alexa Fluor）或与荧光蛋白结合（例如mCherry的）或其它类型的标记（例如，¹²⁵ I，麦芽糖结合蛋白）被用于检测SM或CPE。在这里，我们总结了特定的SM结合蛋白，lysenin和equinatoxin II的特征。CPE和SM /胆固醇（Chol）结合的aegerolysin蛋白，胸膜溶素A ₂，ostreolysin和erylysin A以及SM / Chol结合蛋白nakanori。然后，我们给出了其应用实例，包括其局限性不仅与它们的脂质特异性和结合常数有关，而且还与膜中的脂质组织有关。