摘要
Meaningful evaluation of promoter activity following dissection of various promoter elements requires the production of many transgenic rice plants. For such purposes, we have developed highly effective Agrobacterium-
Meaningful evaluation of promoter activity following dissection of various promoter elements requires the production of many transgenic rice plants. For such purposes, we have developed highly effective Agrobacteriummediated transformation systems. A recently-developed procedure utilizes microspore-derived calli and is capable of generating several hundred transformants per cocultivation event. Importantly, autodiploidization of transgenic haploid plants gives rise to homozygous plants in the first generation. We are currently determining if the autodiploidization frequency of -4% can be increased by exposing calli or young plantlets to colchicine. The promoter for RCg2, a gene encoding a putative lipid transfer factor, can drive strong expression of the GUS reporter in roots of transgenic rice （Xu et al., 1995）. However, it is very susceptible to silencing, reducing its potential value for biotechnological applications （Hall et al., 2001）. In silico analysis of the promoter revealed several putative down-regulating elements, including one centered on a region corresponding to a conserved element of the miniature inverted repeat transposable element （MITE） Janus （Yang and Hall, 2001; Yang and Hall, 2003）. Excision of various motifs from the RCg2 promoter revealed both positive and negative effects on promoter strength and frequency of silencing.
出处
《分子植物育种》
CAS
CSCD
2007年第2期279-279,共1页
Molecular Plant Breeding
关键词
小孢子
种子植物
稻子
转化系统
秋水仙碱
Autodiploidization, Colchicines, Gene silencing, Homozygous transformant, Microspore-derived calli, MITE
