Abstract: Predictable and reliable gene stacking will simplify the breeding process, saving time and resources. The Cre-Lox recombination system offers the ability to easily add, remove, or alter traits for more precise control over plant characteristics. The system uses specific bespoke loxP sites to ensure unidirectional gene insertion, creating a “Loxbox” to prevent further insertions at the same site. This method allows for iterative, targeted gene stacking approach to user-defined genetic engineering by recombination in a plant cell, plant tissue, plant material, plant part, and/or plant with predictable directionality. By creating a toolkit for targeted sequential gene insertion, the trait development pipeline can be streamlined, making it easier and faster to develop new plant varieties with desirable traits.

Abstract: Disclosed herein are novel methods and materials for selecting transgenic cells. Specifically exemplified herein are positive selection methods that involve conferring to cells the ability to metabolize certain compounds, preferably arabitol, ribitol, raffinose, sucrose, mannitol or combinations thereof. Accordingly, transformed cells can be selected by simply subjecting them to a medium containing such compounds. The subject invention alleviates the disadvantages and concerns of negative selection methods, such as the unnecessary killing of transformed cells and the dispersal of potentially harmful genes (e.g., antibiotic or herbicide resistant genes) into the environment. Furthermore, novel nucleotide sequences relating to the E. coli rtl operon and arabitol dehydrogenase gene, and amino acid sequences relating to the gene products thereof are disclosed.

Abstract: Disclosed herein are novel methods and materials for selecting transgenic cells. Specifically exemplified herein are positive selection methods that involve conferring to cells the ability to metabolize certain compounds, preferably arabitol, ribitol, raffinose, sucrose, mannitol or combinations thereof. Accordingly, transformed cells can be selected by simply subjecting them to a medium containing such compounds. The subject invention alleviates the disadvantages and concerns of negative selection methods, such as the unnecessary killing of transformed cells and the dispersal of potentially harmful genes (e.g., antibiotic or herbicide resistant genes) into the environment. Furthermore, novel nucleotide sequences relating to the E. coli rtl operon and arabitol dehydrogenase gene, and amino acid sequences relating to the gene products thereof are disclosed.