TRANSIENT EXPRESSION OF THE BETA-GLUCURONIDASE GENE INTRODUCED INTO UROMYCES-APPENDICULATUS UREDOSPORES BY PARTICLE BOMBARDMENT

Plasmids carrying the beta-glucuronidase gene (GUS) under the control of the promoter from the previously cloned gene specific for infection structure, INF24, were constructed by inserting the INF24 promoter in front of the GUS gene carried in the Bluescript vector. These plasmid DNAs were then introduced into uredospores of the bean rust fungus, Uromyces appendiculatus; the biolistic particle delivery system was used. With germination and differentiation on collodion membranes, GUS activity assayed histochemically with X-gluc was evident only in those germlings that were bombarded with the plasmid containing the entire promoter region; it was not evident in those that were mock-bombarded or bombarded with the plasmid lacking the promoter.