Plant transgene silencing and its controlling

The goal of plant genetic engineering is to obtain transgenic plants that foreign gene can be normally expressed and faithfully inheritted in a predictable manner. But in recent years,it was widely reported that transgene silencing was often found in transgene plant. In this article,we discuss two level of transgene silencing phenomenon: Transcriptional Gene silencing and Posttranscriptional Gene silencing. Its mechanisms involved DNADNA,DNARNA,RNARNA,interaction respectively,and we discuss some strategies to overcome transgene silencing also. Especially,Matrix attachment region(MAR)show capacity to increase level of transgene expression and reduce transformattotransformat variation of transgene expression in stable transformated plant.