EXPRESSION OF A CHEMICALLY SYNTHESIZED GENE FOR HUMAN EPIDERMAL GROWTH-FACTOR UNDER THE CONTROL OF CAULIFLOWER MOSAIC VIRUS-35S PROMOTER INTRANSGENIC TOBACCO

Nicotiana tabacum was transformed with a chemically synthesized gene e ncoding the human epidermal growth factor (hEGF) under control of the CaMV-35S promoter. The hEGF gene sequence was present at one to severa l copies in the primary transformant plants (R0), and a transcript wit h the expected length was produced. Slot blot analysis of total RNAs o f the progeny (R1) seedlings, originating from self-pollination of the R0 plants, showed that the level of mRNA expression was generally, bu t not always, heritable. The highest hEGF peptide content per unit of total soluble protein in young (upper) R1 leaves so far examined by an immunological method was about 0.001%. These results suggest that eit her the hEGF peptide was less stable than the average leaf protein. or the hEGF mRNAs were not efficiently translated.