Crispr-Cas9 or Talen Mediated Genome Editing in Sugarcane

Sugarcane’s exceptional photosynthetic efficiency results in superior biomass and sugar production in support of the emerging bio-economy. While designer nucleases like CRISPR-Cas9 and TALEN can now be widely used to precisely target a specific DNA sequence and cause cleavage in vivo, there is no control over the subsequent NHEJ process that takes place. Hence, although the site of mutation is highly specific, the resultant structure of the mutated locus is largely random and consists of indels of unspecified size and sequence. Associated frameshift mutations will result in loss of function and cause desirable phenotypes in sugarcane if a sufficient number of alleles/copies in the highly-polyploid genome is co-edited.

However, in contrast to these “loss of function mutants” many synthetic biology applications will require the precise conversion of inferior to superior alleles to gain function. Truly precise sequence engineering of an endogenous locus requires template mediated homologous recombination (HR) which competes with the more efficient but error prone NHEJ during DNA repair. We will describe alternative approaches to genome editing in sugarcane, as well as faithful transmission of genome modifications to vegetative progenies and their field performance.