Abstract: Enhancer of Glabra3（EGL3）is a bHLH protein that is an important transcript factor in plant. In order to elucidate the regulation mechanism of EGL3 in‘Tsuda’anthocyanin biosynthesis，cDNA of EGL3 gene was isolated from this plant by the method of RT-PCR using degenerate primers designed according to Arabidopsis EGL3（GenBank accession No. NM202351）. This gene was named BrEGL3 （GenBank accession No. HM208589）. BrEGL3 was 1 794 bp in full length open reading frame（ORF）encoding 597 amino acids with the molecular weight of 66.8 kD. Software prediction results showed that BrEGL3 contained a DNA helix-loop-helix binding domain. Homology analysis showed that the deduced amino acid sequence of BrEGL3 shared the highest similarity with Raphanus sativus EGL3 and the lowest similarity with Lotus angustissimus EGL3. Quantitative-PCR analysis showed that the BrEGL3 was the highest expressed in the in red root epidermis of turnip.

Key words: Brassica campestris L. ssp. rapifera, EGL3, gene cloning, expressing analysis