Objective To analyze the expression of foreign gene in the filial generation of the transgenic plants on the base of the original transgenic tomatoes seeds carrying the gene encoding saliva- binding region（SBR） in PAc of Streptococcus mutans（S. mutans）gained. Methods The tomatoes total DNA was extracted by CTAB methods, and the filial generation transgenic tomatoes carrying the gene encoding SBR in PAc of S. mutans were selected by PCR. The tomatoes total RNA was extracted by trizol and the transcription of the foreign gene was analyzed by RTPCR. Protein was extracted from fruit tissue and the content of the total protein was determined by Bradford′s methods G250. The expression of foreign protein was analyzed by Western blot and the lever of the foreign protein was analyzed by ELISA. Results The fragment encoding SBR in S. mutans PAc gene integrated in the tomato genomic DNA and was expressed. The foreign protein lever was up to 1.2% of the total soluble protein in tomato fruit tissue. Conclusion The foreign protein gene in the filial generation of the transgenic plants could express the foreign protein.
