Luschnig C, Hess M, Pusch O, Brookman J, Bachmair A
Department of Cytology and Genetics, University of Vienna, Austria.
Eur J Biochem. 1995 Mar 15;228(3):739-44. doi: 10.1111/j.1432-1033.1995.0739m.x.
Expression of TyA (reading frame A) of the yeast retrotransposon Ty1 in Escherichia coli is possible by using efficient transcriptional and translational initiation signals. When expressed in E. coli, the gag homologue of Ty1 assembles into spherical particles similar, but not identical to virus-like particles in the natural host of Ty1, Saccharomyces cerevisiae. Deletion analysis reveals a domain in the C-terminus of TyA that is essential for the assembly process. These findings indicate that an early step of the retroelement life cycle, assembly of the gag homologue into spherical particles, does not depend on specific host factors. The experiments also demonstrate that Ty1 Gag fusion proteins, potential tools for immunization, can be produced in E. coli, an organism that lacks endogenous retrotransposons.
通过使用高效的转录和翻译起始信号，酵母逆转录转座子Ty1的TyA（阅读框A）能够在大肠杆菌中表达。当在大肠杆菌中表达时，Ty1的gag同源物组装成球形颗粒，这些颗粒与Ty1的天然宿主酿酒酵母中的病毒样颗粒相似但并不相同。缺失分析揭示了TyA C末端的一个结构域，该结构域对于组装过程至关重要。这些发现表明，逆转元件生命周期的早期步骤，即gag同源物组装成球形颗粒，并不依赖于特定的宿主因子。这些实验还证明，Ty1 Gag融合蛋白作为潜在的免疫工具，可以在缺乏内源性逆转录转座子的大肠杆菌中产生。
