Expression of hepatitis B surface antigen by yeast actin gene promoter.

The promoter sequence (from position -500 to -21) of the yeast actin gene was subcloned into the multiple cloning site of pUC12 to generate a new recombinant plasmid pYAP12. The actin gene promoter can therefore be readily excised from pYAP12 by several restriction enzymes and subsequently placed upstream of the desired protein coding sequence. Results of expression of the hepatitis B surface antigen controlled by the actin gene promoter of pYAP12 in yeast suggest it is a strong functional promoter. To our knowledge, this is the first demonstration of the potential application of the yeast actin gene promoter for expression of foreign proteins in yeast.