Schetelig Marc F, Götschel Frank, Viktorinová Ivana, Handler Alfred M, Wimmer Ernst A
USDA/ARS, Center for Medical, Agricultural and Veterinary Entomology, 1700 SW 23rd Drive, Gainesville, FL 32608, USA.
Genetica. 2011 Jan;139(1):71-8. doi: 10.1007/s10709-010-9494-4. Epub 2010 Sep 16.
Transposon-based vectors currently provide the most suitable gene transfer systems for insect germ-line transformation and are used for molecular improvement of the Sterile Insect Technique. However, the long time stability of genome-integrated transposon constructs depends on the absence of transposase activity that could remobilize the transposon-embedded transgenes. To achieve transgene stability transposon vectors are usually non-autonomous, lacking a functional transposase gene, and chosen so that endogenous or related transposon activities are not present in the host. Nevertheless, the non-autonomous transposon-embedded transgenes could become unstable by the unintended presence of a mobilizing transposase that may have been undetected or subsequently entered the host species by horizontal gene transfer. Since the field release of transgenic insects will present environmental concerns relating to large populations and high mobility, it will be important to ensure that transgene constructs are stably integrated for maintaining strain integrity and eliminating the possibility for unintentional transfer into the genome of another organism. Here we review efficient methods to delete or rearrange terminal repeat sequences of transposons necessary for their mobility, subsequent to their initial genomic integration. These procedures should prevent transposase-mediated remobilization of the transgenes, ensuring their genomic stability.
基于转座子的载体目前为昆虫种系转化提供了最合适的基因转移系统，并被用于不育昆虫技术的分子改良。然而，基因组整合的转座子构建体的长期稳定性取决于转座酶活性的缺失，转座酶活性会使嵌入转座子的转基因重新移动。为了实现转基因的稳定性，转座子载体通常是非自主的，缺乏功能性转座酶基因，并且其选择方式使得宿主中不存在内源性或相关的转座子活性。尽管如此，嵌入非自主转座子的转基因可能会因意外存在可移动的转座酶而变得不稳定，这种转座酶可能未被检测到，或者随后通过水平基因转移进入宿主物种。由于转基因昆虫的田间释放会带来与大量种群和高移动性相关的环境问题，确保转基因构建体稳定整合以维持品系完整性并消除意外转移到其他生物体基因组中的可能性将非常重要。在这里，我们综述了在转座子最初基因组整合后，删除或重排其移动所需的末端重复序列的有效方法。这些程序应能防止转座酶介导的转基因重新移动，确保其基因组稳定性。
