Systems for the removal of a selection marker and their combination with a positive marker

• Published in: Plant cell reports 2001-07, Vol.20 (5), p.383-392
• Main Authors: Ebinuma, H, Sugita, K, Matsunaga, E, Endo, S, Yamada, K, Komamine, A
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biotechnology; Fundamental and applied biological sciences. Psychology; Genetic engineering; genetic markers; Genetic technics; Methods. Procedures. Technologies; site-specific recombination; Transgenic animals and transgenic plants; Transgenic plants
• ISSN: 0721-7714; 1432-203X
• DOI: 10.1007/s002990100344

Many systems have been developed for the removal of a selection marker in order to generate marker-free transgenic plants. These systems consist of (1) a site-specific recombination system (Cre/lox) or a phage-attachment region (attP) to remove the selectable marker gene and (2) a transposable element system (Ac) or a co-transformation system to segregate the gene of interest from the selectable marker gene. Overall, the process is more time-consuming than conventional transformation methods because two rounds of transformation – two steps of regeneration or sexual crossings – are required to obtain the desired transgenic plants. Recently, removal systems combined with a positive marker, denoted as MAT vectors, have been developed to save time and effort by generating marker-free transgenic plants through a single-step transformation. We summarize here the transformation procedures using these systems and discuss their feasibility for practical use.