The Vector Construction And Function Analysis Of A GA-related Protein Phosphatase Gene In Arabidopsis

Protein phosphatases are expressed in almost all eukaryotic cells, participating in many cell development processes, such as meiosis, cell divisions, apoptosis, protein synthesis, metabolism, cytoskeleton reorganization, regulation of membrane receptors and channels. In recent years, there were great progresses in study on plant protein phosphatase, playing an important role in most of the celluar signal transduction pathways of plants.By screening the ethyl methane sulphonate (EMS) mutagenized seeds of Arabidopsis, a mutant pipe was isolated. It was presumed that the gene was involved in the GA signaling pathway by phenotype analysis of pipe, and the gene was identified by map-based cloning techniques, which encoded a protein phosphatase. To further investigate the function of PIPE, we constructed the corresponding expression vectors, which were transformed into pipe and the wild-type by Agrobacterium mediated flower-dipping method subsequently. Over-expression of PIPE in Col induced significantly increased plant height and larger leaf size due to increased cell size. Over-expression of PIPE in pipe partly rescued the mutant phenotype, but which could not recover to the wild type level.At the same time, we used PIPE promoter to drive the GUS gene to study the expression pattern of PIPE. GUS expression was discovered in roots, stems, rosette leaves, cauline leaves and flowers, siliques of transgenic lines, mainly in leaves and petioles of the seedling stage, especially in the meristem tissues, suggesting that PIPE may mainly function in the early stage of organ development. In conclusion, these results provide an experimental basis for further determination of the gene’s function.