TRANSIENT EXPRESSION OF THE GREEN FLUORESCENT PROTEIN IN POLLEN

ZM13 is a pollen-specific maize gene which is expressed in the late st ages of pollen development. We wished to utilize the ZM13 promoter to examine the expression of a synthetic green fluorescent protein (SGFP) in germinating pollen. The usefulness of the SGFP expression product is that its appearance and distribution can be monitored non-destructi vely in vivo. A plasmid containing the SGFP coding region under the co ntrol of the ZM13 promoter was constructed and then transiently transf ormed into pollen of Tradescantia paludosa and Nicotiana tabacum by th e use of microprojectile bombardment. The expression of the green fluo rescent protein was analyzed by fluorescence microscopy using a fluore scein filter. Expression began about 3 h post-bombardment, and all par ts of the pollen grain and tube fluoresced. High levels of fluorescenc e were observed for several days following treatment.