Infections with Various Types of Organisms Stimulate Transcription from a Short Promoter Fragment of the Potato gst1 Gene. Gunter Strittmatter. Max-Planck-lnstitut fur Zuchtungsforschung, Abteilung Biochemie, Carl-von-Linne-Weg 10, D-50829 Koln, Germany. Godefieve Gheysen (2), Vivienne Gianinazzi-Pearson (3), Karoline Hahn(1), Andreas Niebel (2), Wolfgang Rohde (4), and Eckhard Tacke (4). (1) Max-Planck-lnstitut fur Zuchtungsforschung, Abteilung Biochemie, Carl-von-Linne-Weg 10, D-50829 Koln, Germany; (2) Rijksuniversiteit Gent, Laboratorium voor Genetika, Ledeganckstraat 35, B-9000 Gent, Belgium; (3) Laboratoire de Phytoparasitologie, INRA/CNRS, SGAP-INRA, BV 1540, F-21034 Dijon Cedex, France; (4) Max-Planck-lnstitut fur Zuchtungsforschung, Abteilung Pflanzenzuchtung und Ertragsphysiolo-gie, Carl-von-Linne-Weg 10, D-50829 Koln, Germany. MPMI 9:68-73. Accepted 25 September 1995, Copyright 1996 The American Phytopathological Society.

By histochcmical GUS staining, we demonstrate that transcription from a short promoter fragment of the potato gstl gene is locally induced after infection of a host plant with various types of pathogenic or symbiotic organisms. This regulatory unit is not active in noninfected tissues, except root apices and senescing leaves. Measuring the expression of a fusion between the promoter fragment and the gus gene in transgenic plants, therefore, allows comparison of the induction of defense reactions in different types of plant-microbe interactions, in one and the same plant.