关键词: 赤霉素3-β-双氧化酶基因, 基因表达, 功能分析

Abstract: As one of key enzymes involved in gibberellin synthesis，gibberellin 3-beta-dioxygenase（GA3ox）is directly acting on the formation of active GAs，and plays a vital role in the growth and development of plants. In this paper，we reviewed the advances on the cloning and expression pattern of GA3ox gene，as well as the functional effects in the study of higher plants. GA3ox gene has been cloned from Arabidopsis，tobacco，sorghum，poplar and other plants. In the different growth stages of plants and in different tissues，the expressions of GA3ox gene varied，which mainly resulted from the genetic factors of a species，and meanwhile，were affected by the environmental factors and exogenous hormones. Studies on mutants of GA3ox revealed that the gene mutations hindered the GA biosynthesis and thus indirectly affected the growth of plant，resulted in the phenotype changes of plant stalk，flowers，seeds，fruit and roots，including plant dwarf and seeding difficulties. Overexpression of GA3ox promoted the production of GA，such as the induction of cell division and differentiation，the radial elongation of root tip，and seed germination. Here studying the relevant functions of GA3ox in different plants and discussing its role in plant growth and development is aimed to provide reference for understanding the regulatory mechanisms of GA3ox on plant growth and development，and to better use the GA3ox in genetic engineering research for directly breeding of new plant varieties in practice.

Key words: gibberellin 3-beta-dioxygenase gene, gene expression pattern, function analysis