Advances in the selection of transgenic plants using non‐antibiotic marker genes

Abstract

Production of transgenic plants started more than a decade ago, but it is still a time-consuming operation. One of the critical points is the selection procedure used for the recovery of transgenic shoots after transformation. Moreover, as more transgenic traits are to be incorporated into crops that already have been transformed, it is clear that there is a need for new methods with higher efficiencies. In this article, recently developed selection systems are reviewed. They differ from conventional selection techniques as they are based on supplementing the transgenic cells with a metabolic advantage rather than killing the non-transgenic cells. In many cases, these new selection systems have been found to be superior to conventional methods.

Agrobacterium mediated transformation of banana (Musa sp.) cv. Sukali Ndiizi (ABB) with a modified Carica papaya cystatin (CpCYS) gene

“…Similar results were obtained by Arinaitwe (2008) and Ghosh et al (2009). One of the critical steps after transformation is the selection procedure used for the recovery of transgenic shoots (Joersbo, 2001). This is because embryogenic cell colonies obtained during the selection procedure must survive the stress induced by the combination of media and antibiotics used to kill both Agrobacterium and untransformed plant cells (Arinaitwe, 2008).…”

Plant native tryptophan synthase beta 1 gene is a non-antibiotic selection marker for plant transformation

“…However, the use of antibiotic resistance markers has been the target of societal concerns, due to a possible deleterious eVect on other organisms in the ecosystem caused by the use of antibiotics, so the development of new markers for risk-free genetic engineering for crop improvement is greatly needed (Daniell et al 2001b;Miki and McHugh 2004). Various positive plant selection systems involving toxic selection agents and marker genes derived from other organisms have been described (Ebmeier et al 2004;Haldrup et al 1998b;Joersbo 2001;Leyman et al 2004), in these systems the decaying untransformed cells may inhibit the growth of living transformed cells by secreting inhibitors or blocking essential nutrient supply. However, inserting a selection marker gene derived from a microorganism into foods may raise ethical questions and invoke safety concerns.…”

“…Therefore, to Wnd an eVective selectable marker, antibiotic or herbicide-resistant genes have been used to simplify detection procedures for putatively transformed plants Miki and McHugh 2004). The existing selection systems can be divided into two groups: conventional selection systems, the largest group, which rely on an antibiotic or herbicide as the selective agent detoxiWed by a selective gene (Joersbo 2001) and positive selection systems, whereby the selective agent is converted into a simple compound by the selective gene product, and transformed cells have metabolic or developmental advantages (Erikson et al 2004;Wenck and Hansen 2005). Currently more than 50 selection systems have been reported, but only few are frequently used in plant transformation (Miki and McHugh 2004;Tian et al 2006).…”

The effect of carbon source on in vitro organogenesis of chrysanthemum thin cell layers

“…Using the xylose isomerase gene as a selector gene, transformation efficiencies were shown to be higher in potato and tomato, but lower in tobacco compared to kanamycin-based selection systems (HALDRUP et al, 1998a(HALDRUP et al, ,b, 2001). The PMI gene has already been successfully utilized for the genetic transformation of sugar beet, potato, oil seed rape and maize (JOERSBO, 2001). …”