ENGINEERING OF THE 5-ENOLPYRUVYLCHIKIMATO-3-PHOSPHATE SYNTHASE (EPSPS) GENE FOR GLYPHOSATE RESISTANCE IN SUGARCANE

Abstract

Sugarcane (Saccharum spp.), a crop of great economic importance for Brazil and the world, has its productivity and production costs affected by weed infestations. The herbicide glyphosate and transgenic plants tolerant to it are widely used to control invasive plants. However, there are still no commercial sugarcane varieties tolerant to glyphosate. The enzyme EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) is the target of glyphosate, and some point mutations confer resistance to the herbicide. Recently, gene editing approaches have been used to install these mutations in the EPSPS gene. However, these mutations commonly reduce the catalytic activity of EPSPS, causing deleterious effects in homozygous plants.This project hypothesizes that it is possible to introduce modifications to the sugar cane EPSPS gene, so that the enzyme is resistant to glyphosate and that there is compensation for the reduction in the catalytic activity of the protein. To this end, gene constructions will be developed, which will be evaluated by transient expression in sugarcane tissues and in transgenic plants. If the initial hypothesis is proven, edited plants will be produced, as a way of validating the potential of the technology using gene editing.