The RAD2 Family of Nucleases in Higher Plants

Abstract

The RAD2 family of nucleases is a group of essential nucleases involved in 3R mechanisms (DNA replication, DNA repair and DNA recombination). The RAD2 family consists of three classes (XPG/ class I, FEN-1/class II and EXO1/class III). Recent advances in plant genome projects have revealed that in addition to plant counterparts belonging to each class of the RAD2 family higher plants have a fourth set of RAD2 family members that constitute a new class in the RAD2 family (SEND-1/class IV). DNA damage generated by endogenous or exogenous factors cause mutations that threaten the survival of plants if they are misrepaired or not repaired, which results in low crop yields. Understanding the functions of plant RAD2 family members in DNA repair is important for agricultural technology enabling an enhancement of resistance to genotoxic stresses caused by DNA damages. In this review, recent advances in our understanding of plant RAD2 family members are discussed.

Structural Aspects of DNA Repair and Recombination in Crop Improvement

“…Flap Endonuclease 1 (FEN1) belongs to the Rad2/XPG family of nucleases. Members of the RAD2 family are involved in DNA replication (FEN1), repair (FEN1, XPG, EXO1), and recombination (GEN1, SEND1) (Lieber, 1997;Furukawa and Shimada, 2009;Tsutakawa et al, 2011). FEN1 has endonuclease as well as 5 -3 exonuclease activities.…”