Abstract

Crossover is a highly conserved process in eukaryotes. For example, all species use the SPO11 endonuclease to generate DNA double strand breaks (DSBs), which are repaired as COs. TAL -effector nucleases (TALENs) consist of a TAL -effector DNA binding domain fused to a nuclease domain. The DNA binding domain contains a stretch of approximately 30 tandem repeats. Each repeat contains two consecutive amino acid positions which are hyper variable – termed the repeat variable diresidue (RVD). Every repeat binds a single base of DNA and the base specificity of the repeat is determined by the identity of the RVD (NI:A, NG:T, NN:G, HD:C). This cipher allows for the creation of TALE Ns targeted to practically any DNA sequence.

In this project we aim to develop a system where artificial DSBs can be directed to specific sequences during meiosis to manipulate CO patterns. In order to create sequence-directed DSBs we will make use of TALENS . This will be used as a tool to investigate control of CO patterns and will also serve as proof-of-principle for crop breeding technologies.