Hu Yuanlei

Expression of ipt gene driven by tomato fruit specific promoter and its effects on fruit development of tomato

Fruit specific promoter (2A12) from Lycopersicom esculentum and cDNA of isopentenyl-transferase (ipt) from Ti plasmid of Agrobacterium tumerfaciens C58 were cloned by PCR procedure respectively. Two plant expression vectors with 2A12/gus or 2A12/ipt were respectively constructed. These two chimeric genes were transferred into tomato by Agrobacterium mediated procedure. The results of Southern hybridization showed that the fusion genes had been integrated into tomatoes. The result of gus histochemical staining showed that 2A12 had high fruit specific expressive capability in transgenic tomato. The ipt expression resulted in accumulation of high level of cytokinins (CTKs) in fruit lead to developmental changes in fruits and seeds. The fruit of ipt transformed tomato had the hyperplastic placenta with very few seeds or even seedless. The shelf life of transgenic fruits elongated for 1–2 weeks. The ratio of fruit set, the dry weight of fruit and the crude protein content in fruit were increased, while the soluble sugar of fruits decreased.

Research strategy for model medicinal species

Use of model organisms in biology research enables understanding of mechanisms and properties of biological systems. The investigation of model organisms has also led to the development of experimental techniques for different areas of biology. Species like Ganoderma lucidum and Salvia miltiorrhiza have been nominated for candidate model medicinal organisms. In this review, we discuss the concept of model medicinal organisms and define the aims of its research. Then, we analyze the feasibility of applying model organism research strategies to medicinal species. We also summarize the selection criteria for model medicinal organisms. Further, we introduce strategies for creating model medicinal organisms from different aspects including genome sequencing, genetic transformation platforms, and mutagenesis. Finally, we discuss the application of the model medicinal species system in gene function analysis, metabolic pathways, and biosynthetic metabolite analysis. We conclude that the model medicinal organism system will enhance understanding of the genetic basis of synthetic metabolites and accelerate the improvement of medicinal species research.