Background : Ginseng seeds are harvested in immature stages and take 3 - 4 month to be germinated following cold stratification. Improvement of germination speed can be a valuable traits to be characterized for economically important medicinal plant. Modulation of cell wall compositions is also considered as another agricultural trait when the crops can be processed for foods and forages. Here we show the functional characterization of ginseng pPLAIIIβ focused on its possible values on germination and modulation of cell wall compositions. Methods and Results : Patatin-related phospholipase AIII family genes were identified from ginseng EST clones and further confirmed by PCR. Clone showing the highest homology with pPLAIIIβ was overexpressed in model plant Arabidopsis, and it displayed dwarf plants. qPCR analysis showed that pPLAIIIβ expressed in all organs of 2-years-old ginseng. Overexpression of ginseng pPLAIIIβ also displayed apparently enlarged seeds as well as altered germination speed in early stage compared to the control. Chemical stainings and direct quantification of lignin and cellulose were performed to understand the link of cell elongation patterns and cell wall compositions. Conclusion : Overexpression of ginseng pPLAIIIβ inhibited longitudinal cell elongation in all tested organs except seeds which is enlarged in both directions than the control. Shorter root length is related with auxin responsive genes and its dwarf morphological phenotype is resulted in altered cell wall compositions.

Background : Prenyltransferases catalyze the sequential addition of IPP units to allylic prenyl diphosphate acceptors and are classified as either trans-prenyltransferases (TPTs) or cis-prenyltransferases (CPTs). Although CPTs and TPTs share similar substrate preferences and reaction products, they can be easily distinguished by their primary amino acid sequences. The characterization of cis-prenyltransferases has been less studied than that of trans-prenyltransferases. Methods and Results : Gene expression patterns of PgCPT1 was analyzed by qRT-PCR. In planta transformation was generated by floral dipping using Agrobacterium tumefaciens. Yeast transformation was performed by lithium acetate and heat-shock for rer2Δ complementation and yeast-two-hybrid assay. Ginseng genome contains at least one family of three putative CPT genes. PgCPT1 is expressed in all organs, but more predominantly in the leaves. Overexpression of PgCPT1 did not show any plant growth defect, and can complement yeast mutant rer2Δ via possible protein-protein interaction with PgCPTL2. Conclusion : Partial complementation of the yeast dolichol biosynthesis mutant rer2Δ suggested that PgCPT1 is involved in some of dolichol biosynthesis. Direct protein interaction between PgCPT1 and a human Nogo-B receptor homolog suggests that PgCPT1 requires an accessory component for proper function.