The binary vectors which respectively contain chimeric genes (SCaM1-GFP, SCaM4-GFP) were constructed and used to transform tobacco (Nicotiana tabacumL.), pGTV-GFP was used as control. The plasmolyzed cells of transgenic callus treated with CBW were investigated under the laser scanning confocal microscope. Green fluorescence was found in the cell wall of transgenic SCaM1-GFP callus. However there was no green fluorescence in the cell wall of SCaM4-GFP or GFP transgenic callus. These results indicate that SCaM1 can be secreted into the apoplast of plant cells, while SCaM4 does not exist in the apoplast of plant cells.
