A chemical-inducible Cre-LoxP system allows for elimination of selection marker genes in transgenic apricot

作者：Petri, Cesar^*; Lopez-Noguera, Sonia; Wang, Hong; Garcia-Almodovar, Carlos; Alburquerque, Nuria; Burgos, Lorenzo

来源：Plant Cell, Tissue and Organ Culture, 2012, 110(3): 337-346.

DOI：10.1007/s11240-012-0155-4

• Fruit trees
• Genetic engineering
• Marker-free
• Prunus armeniaca
• Site-specific recombination
• beta-Estradiol

Transgenic plant development relies on the introduction of marker genes along with the gene(s) of interest to select and/or identify transgenic regenerants. Due to public concerns and regulatory issues, it would be advantageous to eliminate these marker genes once they are no longer needed. The chemical-inducible Cre-LoxP system is especially suitable for clonally-propagated plants, such as fruit trees, as no sexual crosses or rounds of transformation are required for marker-gene elimination. In this study, four transgenic pX6-GFP apricot (Prunus armeniaca L.) (cv. Helena) lines, carrying the gfp reporter gene encoding for the green fluorescent protein, were obtained following Agrobacterium tumefaciens-mediated transformation of leaf explants. The DNA site-specific recombination was precise and tightly controlled by the inducer beta-estradiol. Expression of the gfp gene was only detected when 3 mu M beta-estradiol was added to the medium. When nodal explants were incubated on a meristem development medium supplemented with 3 mu M beta-estradiol, marker gene elimination was observed in buds of all four transgenic lines, at an average frequency of 11.3 %, based on GFP expression. Further molecular analyses of four GFP-positive shoots, a single shoot from each transgenic line, revealed that DNA recombination was complete in two of shoots, but incomplete in the other two shoots.

• 出版日期2012-9
• 单位甘肃省农业科学院