Structure Analysis of a Pathogenesis-Related 10 Protein from Gardenia jasminoides

Abstract

The PR-10 proteins belongs to the huge family of pathogenesis related proteins ubiquitous in the plant kingdom, and it includes major food and tree pollen allergens, major latex proteins (MLPs) and cytokinin-specific binding proteins(CSBPs). In this work, a fruit cDNA library of Gardenia jasminoides was constructed, and the GjPR10 cDNA was isolated from the library by sequencing method. The GjPR10 cDNA contains a predicted 486 bp open reading frame, the putative protein contains 161 amino acids, and the protein has a calculated molecular mass 17.7kDa and a theoretical pI 6.25, these characters consistent with usual plant PR10 protein features. A bioinformatics analysis was conducted with previously characterized PR-10 proteins from other plant species. A three-dimensional model of GjPR10 was built. The bioinformatics analysis suggests that the GjPR10 present the conserved P-loop motif. The three-dimensional structure of GjPR10 has the significant common feature of PR10 proteins, it is composed of three alpha-helices and a seven-stranded antiparallel beta-sheet arranged to form a large internal hydrophobic cavity. The results suggest that GjPR10 is a typical PR10 protein, GjPR10 might be involved in plant defence response, developmental processes and in secondary metabolism.