Synthesis and processing of equine herpesvirus type 1 glycoprotein 14.
Synthesis and processing of equine herpesvirus type 1 glycoprotein 14.
复制标题
马疱疹病毒1型糖蛋白14的合成和加工。
DOI：
10.1016/0042-6822(89)90576-x
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发表时间：
1989
期刊：
影响因子：
3.7
通讯作者：
O'Callaghan,DJ
中科院分区：
文献类型：
--
作者：
Sullivan,DC;Allen,GP;O'Callaghan,DJ
采用一组单克隆抗体研究了马疱疹病毒1型（EHV-1）糖蛋白14（gp 14），即单纯疱疹病毒（HSV）糖蛋白B（gB）的同源物，以确定该多肽的调节类别、合成速率和糖基化类型。免疫沉淀、蛋白质印迹和SDS-PAGE分析与代谢抑制剂联合使用的应用（放线菌酮，放线菌素D，膦酰基乙酸，衣霉素，莫能菌素），时间过程和脉冲追踪实验揭示了以下信息：（1）在EHV-1感染的细胞提取物中存在三种gp 14相关多肽，分子量分别为138千道尔顿（K）、77- 75 K和55- 53 K。(2)所有这三种物质都是在DNA合成抑制剂膦酰乙酸存在下合成的，尽管它们的合成被DNA复制增强，表明是β-γ类分子。(3)138 K物质首先被合成，作为较小的gp 14物质，即77- 75 K和55- 53 K形式的前体。(4)使用糖基化抑制剂和用内切糖苷酶消化免疫沉淀的gp 14表明，主要的翻译产物是118 K分子，其通过加入高甘露糖寡糖而共价糖基化为138 K形式。(5)77- 75 K种类含有高甘露糖和杂合寡糖，而55- 53 K形式的gp 14含有一些复杂寡糖。(6)在不存在还原剂的情况下，在感染的细胞提取物和纯化的病毒体中均观察到138 K多肽和大的145 K物质。因此，EHV-1 gp 14似乎是作为138 K的大前体分子合成的，并被蛋白水解切割成两种较小的形式，77- 75 K和55- 53 K，它们通过二硫键连接形成145 K复合物。这种gp 14合成和成熟的模型类似于在α疱疹病毒中发现的许多HSV gB等价物的模型。
Glycoprotein 14 (gp14) of equine herpesvirus type 1 (EHV-1), the homolog of herpes simplex virus (HSV) glycoprotein B (gB), was investigated employing a panel of monoclonal antibodies to ascertain the regulatory class, rate of synthesis, and type of glycosylation of this polypeptide. Application of immunoprecipitation, Western blot, and SDS-PAGE analysis in conjunction with the use of metabolic inhibitors (cycloheximide, actinomycin D, phosphonoacetic acid, tunicamycin, and monensin), and time-course and pulse-chase experiments revealed the following information: (1) Three gp14-related polypeptides with molecular weights of 138 kilodaltons (K), 77-75K, and 55-53K are present in EHV-1-infected cell extracts. (2) All three species are synthesized in the presence of the DNA synthesis inhibitor phosphonoacetic acid although their synthesis is enhanced by DNA replication, indicative of a β-γ class molecule. (3) The 138K species is synthesized first as a precursor of the smaller species of gp14, the 77-75K and 55-53K forms. (4) Use of glycosylation inhibitors and digestion of immunoprecipitated gp14 with endoglycosidases indicate that the primary translation product is a 118K molecule which is cotranslationally glycosylated to the 138K form by the addition of high mannose oligosaccharides. (5) The 77-75K species contains both high mannose and hybrid oligosaccharides while the 55-53K form of gp14 contains some complex oligosaccharides. (6) In the absence of a reducing agent, the 138K polypeptide and a large 145K species are observed in both infected cell extracts and purified virions. Thus, EHV-1 gp14 appears to be synthesized as a large precursor molecule of 138K and is proteolytically cleaved to two smaller forms, 77-75K and 55-53K, which are linked by a disulfide bond(s) to form a 145K complex. This model of gp14 synthesis and maturation is similar to those proposed for a number of HSV gB equivalents found in the Alphaherpesvirnae.