TISSUE-SPECIFIC EXPRESSION OF PLANT DEFENSIN GENES PDF2.1 AND PDF2.2 IN ARABIDOPSIS-THALIANA

Plant defensins are a family of cysteine-rich peptides, many members o f which have been shown to exhibit antimicrobial activity. Sequence an alysis of randomly expressed sequence tags has revealed the presence o f five different plant defensin genes in Arabidopsis thaliana. previou s work has established the tissue-specific expression pattern of PDF1. 1, PDF1.2 and PDF2.3. The present study reports on the expression patt erns of PDF2.1 and PDF2.2. A compilation of all available data indicat es that all Arabidopsis organs constitutively express one, and most of them two or more, plant defensin genes. Expression of PDF1.2 is upreg ulated upon infection of leaves by a fungal pathogen, while that of PD F2.2 is down regulated. (C) Elsevier, Paris.