| 摘要 |
<p>There are described a number of plasmid vectors suitable for the expression of genetic material, at various levels in yeasts. The plasmids each comprise a yeast selective marker, a yeast replication origin and a yeast promoter positioned relative to a unique restriction site in such a way that expression may be obtained of a polypeptide coding sequence inserted at the restriction site. The promoters used are derived from the 5' region of a gene coding for a yeast glycolytic enzyme e.g. phosphoglycerate kinase (PGK), or from the 5' region of the yeast TRP1 gene. In one Example a plasmid contains a promoter derived from both the 3' and 5' regions of the PGK gene. The replication systems used involve the yeast 2µ replication origin or an autonomous replicating sequence (ARS) stabilised with an ARS stabilising sequence (ASS). The replication systems allow for a choice of high or low copy number per cell. The promoter sequences allow for a choice of high or low expression level. A kit including vectors having a combination of these alternative features is described. Yeast expression vectors including a gene for coding for human interferon-a are described.</p> |
