Scaria A, Tollefson A E, Saha S K, Wold W S
Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, Missouri 63104.
Virology. 1992 Dec;191(2):743-53. doi: 10.1016/0042-6822(92)90250-s.
The 11,600 MW (101 amino acids; 11.6K) protein of adenovirus 2 (Ad2) is a protein of unknown function which is synthesized in low amounts during early stages of infection but in very high amounts at late stages. The 11.6K protein migrates as three major groupings of diffuse bands of ca. 14K, 21K, and 31K on SDS-PAGE, indicating that 11.6K undergoes post-translational modification. We show here that 11.6K is Asn-glycosylated with complex (endo H-resistant) oligosaccharides and that 11.6K is an integral membrane protein. Immunofluorescence indicated that 11.6K initially is associated with the endoplasmic reticulum and Golgi apparatus and that it ultimately localizes to the nuclear membrane. The 11.6K protein is predicted to have a single signal-anchor sequence at residues 41-62 and only one potential Asn-linked glycosylation site at residue 14; thus, 11.6K must be oriented in the membranes with its NH2-terminus in the lumen and its COOH-terminus in the cytoplasm. The signal-anchor and glycosylation features of 11.6K are preserved in Ad2 and Ad5 (group C), and in Ad3 and Ad7 (group B), but the sequence of 11.6K is more diverged among these serotypes than is the sequence of most other adenovirus proteins.
腺病毒2型（Ad2）的11.6千道尔顿（101个氨基酸；11.6K）蛋白是一种功能未知的蛋白，在感染早期合成量较低，但在晚期合成量非常高。11.6K蛋白在SDS-PAGE上迁移为大约14K、21K和31K的三个主要弥散条带组，表明11.6K经历了翻译后修饰。我们在此表明，11.6K被复杂（内切糖苷酶H抗性）寡糖进行了天冬酰胺糖基化，并且11.6K是一种整合膜蛋白。免疫荧光表明，11.6K最初与内质网和高尔基体相关，最终定位于核膜。预测11.6K蛋白在第41 - 62位残基处有一个单一的信号锚定序列，在第14位残基处只有一个潜在的天冬酰胺连接糖基化位点；因此，11.6K在膜中的取向必须是其NH2末端在腔内，COOH末端在细胞质中。11.6K的信号锚定和糖基化特征在Ad2和Ad5（C组）以及Ad3和Ad7（B组）中得以保留，但11.6K的序列在这些血清型之间比大多数其他腺病毒蛋白的序列差异更大。
