RNAi-mediated male sterility of tobacco by silencing TA29.
The superior performance of F1 hybrids has a significant impact on agricultural productivity. For commercial application, the availability of an efficient system for obtaining male-sterile lines of crops is an essential prerequisite. Here we have investigated the use of RNA interference (RNAi) technology to silence a male-specific gene in the model host tobacco. TA29 is expressed exclusively in anthers at the time of microspore development. About 10 out of 13 tobacco lines transformed with a hairpin RNAi construct containing TA29 sequences were male sterile. Transgenic plants were phenotypically indistinguishable from non-transgenic plants. At the anthesis stage, pollen grains from transgenic, male-sterile plants were aborted and lysed in comparison to the round and fully developed pollen in non-transgenic plants. Microscopic analysis of anthers showed selective degradation of tapetum in transgenic plants with no microspore development. One week after self-pollination, the ovules of non-transgenic plants were double the size of those in transgenic plants, due to successful self-fertilization. Male sterile transgenic plants set seed normally, when cross-pollinated with pollen from non-transgenic plants, confirming no adverse effect on the female parts of the flower. These results show that silencing of male-specific genes by RNAi is potentially a useful tool for generating male-sterile lines for producing hybrid seed.
Nawaz-ul-Rehman
Muhammad Shah
MS
National Institute for Biotechnology and Genetic Engineering, Jhang Road, Faisalabad, Pakistan.
Mansoor
Shahid
S
Khan
Asif Ali
AA
Zafar
Yusuf
Y
Briddon
Rob W
RW
D020868:Gene Silencing; D017343:Genes, Plant; D006824:Hybridization, Genetic; D051479:Plant Infertility / Q000235:genetics*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D014026:Nicotiana / Q000033:anatomy & histology / Q000187:drug effects* / Q000235:genetics*; D014170:Transformation, Genetic
D034741:RNA, Small Interfering