Cloning and genetic transforming of BjPKS1 in tumourous stem mustard（ Brassica juncea var. tumida Tsen et Lee）

Tumourous stem mustard（ Brassica juncea var. tumida Tsen et Lee） is an economically and nutritionally important vegetable crop of the Cruciferae family that also provides the raw material for Fuling mustard. In the previous studies，a gene may be associated with the tumor stem swelling was obtained，which was similar to PKS1 gene in Arabidopsis thaliana. In this study，through RACE technology，the full lenth sequence was cloned and named BjPKS1. It had 1 440 bp cDNA and a complete opening reading frame（ ORF） of 1 131 bp，containing the initial code（ ATG） and terminal code（ TAG）（ accession number: JN714279）. The predicted protein of complete ORF comprised 376 amino acids. From a search for BjPKS1 cDNA and amino acid sequences in the database，it had highly sequence identity with the PKS1 protein from A. thaliana. We proposed that BjPKS1 may play the same role as PKS1.In addition，expression of BjPKS1 in development of tumor stem swelling was studied by quantitative RT-polymerase stem swelling. The BjPKS was genetic transformed to A. thaliana，and the plant height and internode were significantly shorter than WT.