The mouse neuronal cell surface protein F3: a phosphatidylinositol-anchored member of the immunoglobulin superfamily related to chicken contactin.
The mouse neuronal cell surface protein F3: a phosphatidylinositol-anchored member of the immunoglobulin superfamily related to chicken contactin.
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小鼠神经元细胞表面蛋白F3：与鸡接触蛋白有关的免疫球蛋白超家族的磷脂酰肌醇锚定成员。
DOI：
10.1083/jcb.109.2.775
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发表时间：
1989-08
影响因子：
7.8
通讯作者：
Goridis, C
中科院分区：
文献类型：
--
作者：
Gennarini, G;Cibelli, G;Rougon, G;Mattei, M G;Goridis, C
IG超家族的几个成员在神经细胞上表达，在那里它们参与细胞体和过程之间的表面相互作用。它们的IG结构域彼此之间的相关性比与IG可变和恒定结构域之间的相关性更密切，并且已被分组为C2组。在这里，我们报告的另一个成员，这组小鼠神经元细胞表面抗原F3的克隆和表征。F3 cDNA序列包含一个开放阅读框，可编码一个1，020个氨基酸的蛋白质，该蛋白质由一个信号序列、六个C2型Ig样结构域、一个长的前膜区（包含两个与纤连蛋白III型重复序列具有序列相似性的片段）和一个中等疏水性的COOH末端序列组成。该蛋白不含典型的跨膜片段，但似乎通过磷脂酰肌醇锚附着于膜上。针对F3蛋白的抗体识别小鼠脑中突出的135-kD蛋白。在胎脑培养物中，它们染色神经元细胞表面，并且在化学成分确定的培养基中维持的培养物中，最显著地染色神经突和神经突束。小鼠f3基因定位于15号染色体的F带。通过F3 cDNA探针在脑中检测到的基因转录物是发育调节的，最高量在出生后1和2周之间表达。F3核苷酸和推导的氨基酸序列与最近发表的鸡神经元细胞表面蛋白contactin的序列具有惊人的相似性。然而，这两种分子之间存在重要差异。与F3相反，接触蛋白具有跨膜和胞质结构域。尽管接触蛋白不溶于非离子去污剂并且与细胞骨架紧密结合，但约等量的F3分布在缓冲液可溶性、非离子去污剂可溶性和去污剂不溶性级分之间。在其他神经细胞表面蛋白中，F3最类似于神经细胞粘附蛋白L1，其胞外结构域之间具有25%的氨基酸同一性。基于其结构与已知的神经组织细胞粘附蛋白，特别是与L1的相似性，我们建议F3介导神经系统发育过程中的细胞表面相互作用。
Several members of the Ig superfamily are expressed on neural cells where they participate in surface interactions between cell bodies and processes. Their Ig domains are more closely related to each other than to Ig variable and constant domains and have been grouped into the C2 set. Here, we report the cloning and characterization of another member of this group, the mouse neuronal cell surface antigen F3. The F3 cDNA sequence contains an open reading frame that could encode a 1,020-amino acid protein consisting of a signal sequence, six Ig-like domains of the C2 type, a long premembrane region containing two segments that exhibit sequence similarity to fibronectin type III repeats and a moderately hydrophobic COOH-terminal sequence. The protein does not contain a typical transmembrane segment but appears to be attached to the membrane by a phosphatidylinositol anchor. Antibodies against the F3 protein recognize a prominent 135-kD protein in mouse brain. In fetal brain cultures, they stain the neuronal cell surface and, in cultures maintained in chemically defined medium, most prominently neurites and neurite bundles. The mouse f3 gene maps to band F of chromosome 15. The gene transcripts detected in the brain by F3 cDNA probes are developmentally regulated, the highest amounts being expressed between 1 and 2 wk after birth. The F3 nucleotide and deduced amino acid sequence show striking similarity to the recently published sequence of the chicken neuronal cell surface protein contactin. However, there are important differences between the two molecules. In contrast to F3, contactin has a transmembrane and a cytoplasmic domain. Whereas contactin is insoluble in nonionic detergent and is tightly associated with the cytoskeleton, about equal amounts of F3 distribute between buffer-soluble, nonionic detergent-soluble, and detergent- insoluble fractions. Among other neural cell surface proteins, F3 most resembles the neuronal cell adhesion protein L1, with 25% amino acid identity between their extracellular domains. Based on its structural similarity with known cell adhesion proteins of nervous tissue and with L1 in particular, we propose that F3 mediates cell surface interactions during nervous system development.