DNA repair and recombination in plants

Abstract

DNA damage can be caused by a large number of internal and external, biotic and abiotic sources and can affect cell viability and can lead to mutations. Depending on the type of damage, different evolutionarily conserved repair pathways are used. Some specific lesions caused by UV radiation and DNA alkylation can be repaired by direct enzymatic reversal. The base excision repair pathway is used for the removal of a variety of damaged bases. When larger modifications of nucleotides are present, the nucleotide excision repair pathway is active. The mismatch repair pathway can reverse the incorporation of noncomplementary nucleotides by replicative polymerases. DNA double-strand breaks can be repaired by the pathways of nonhomologous end-joining, single-strand annealing, and homologous recombination which lead to different outcomes. Different DNA damage tolerance and repair pathways can deal with DNA lesions at damaged replication forks. Repair of DNA has to be tightly regulated with respect to other cellular processes. DSB repair pathways form the basis for recently developed techniques for directed modification of genomes for research and agronomy. When larger modifications of nucleotides are present, the nucleotide excision repair pathway is active. The mismatch repair pathway can reverse the incorporation of noncomplementary nucleotides by replicative polymerases. DNA double-strand breaks can be repaired by the pathways of nonhomologous end-joining, single-strand annealing, and homologous recombination which lead to different outcomes. Different DNA damage tolerance and repair pathways can deal with DNA lesions at damaged replication forks. Repair of DNA has to be tightly regulated with respect to other cellular processes. DSB repair pathways form the basis for recently developed techniques for directed modification of genomes for research and agronomy.