Expression of pepper cyclophilin gene is differentially regulated during the pathogen infection and abiotic stress conditions

Abstract

A pathogen induced pepper cyclophilin (CACYP1) cDNA clone was isolated from a pepper cDNA library from hypersensitive response (HR) lesions of leaves infected with Xanthomonas campestris pv. vesicatoria using a differential hybridization technique. The deduced amino acid sequences OF this CACYP1 gene have high levels of, identity with those Of cyclophilin genes from tomatoes, potatoes, beans and Arabidopsi.. The CACYP1 mRNA was constitutively expressed in the leaf, stem, root and flower, but not in the green unripe: and the red (ripe) fruits of pepper plants. The accumulation of CACYP1 mRNA was strongly induced in pepper plants by X. campestris pv. vesicatoria and Colletotrichum gloeosporioide. infections. In the incompatible interaction, a drastic induction of the CACYP1 mRNA occurred in the bacteria inoculated leaves compared to that of the compatible interaction. Prior inoculation with an avirulent strain of X. campestris pv. vesicatoria in lower leaves resulted in a strong, systemic CACYP1 mRNA accumulation in the uninoculated upper leaves. A situ hybridization results revealed that CACYP1 mRNA was localized in the phloem cells of vascular tissues in pepper fruits infected by C. gloeosporioides. Treatment with salicyclic acid and methyl jasmonate strongly induced the CACYP1 transcripts in pepper leaves. (C) 2001 Academic Press.