Genetic Transformation Of BR Related Gene HSD1on Maize

Glucocorticoids are a class of animal steroid hormones involved in metabolic,inflammatory, cardiovascular, and behavioral processes. The enzyme11-β-hydroxysteroiddehydrogenase (HSD) is a key regulator of the level of glucocorticoids and catalyzes theinterconversion of biologically active glucocorticoid and inactive glucocorticoid. HSD1overexpression can break seed dormancy, promote seed germination, and increase plantbiomass. In this article, ZmHSD1gene was introduced into maize inbred lines Chang7-2,Qi319and18-599by Agrobacterium tumefaciens, and NPTII gene was used as selectivemarker. The main results of this study were as follows:1. Transgenic plantlets were obtained from resistant maize calli and the seeds of T0generation transgenic plant obtained through selfing. Among them, there were183plants ofQi319,686plants of18-599and30plants of Chang7-2.2. Molecular analysis of the regenerated plantlets showed that there were positive ones inthree test materials that proved the target gene ZmHSD1has been transformed into the testmarerials.21transgenic plants of18-599,10transgenic plants of Qi319and2transgenicplants of Chang7-2with PCR were positive. In the PCR-positive transgenic plants,1plants ofQi319and7plants of18-599were RT-PCR-positive. According to southern blotting, total of11plants were positive, included8plants of18-599and3plants of Qi319, indicating that thetarget gene is integrated into the genome, suggesting that the single-copy gene in the genomesequence.