Abstract:

Plants are often subjected to DNA damage due to a range of environmental and internal factors in the natural world. Among these factors, DNA double strand breaks（DSBs）have the most serious consequences to plants. If these DSBs are repaired improperly, which may result in genome instability, gene mutations, and even cell death. On one hand, plants have evolved a powerful and well-organized damage repair mechanism to ensure overall survival and normal reproduction. On the other hand, based on the fault-tolerance and mutagenicity of the repair process, a series of techniques such as T-DNA insertion, gene editing, and physical mutagenesis have been widely used for variety improvement in plants and animals. Compared with mammals, reports on DSBs repair pathways and their molecular mechanisms in plants are limited. In this paper, we review the responses of plants to DSBs damage and the main repair mechanisms, and we also focus on the recent advances in alternative end joining（Alt-EJ）, whose mechanism has not yet been fully revealed. In addition, we discuss the characteristics and multi-pathway options of DSBs repair in plants induced by heavy ion beams irradiation, and the progress of gene editing technology based on different DSBs repair pathways. This study aims to provide reference for understanding the molecular mechanism of plant DSBs damage response and developing efficient biological breeding technology.

Key words: damage repair of plant DSBs, homologous recombination, non-homologous end joining, heavy ion beams, gene editing