Send to

Choose Destination
PLoS Genet. 2017 May 31;13(5):e1006827. doi: 10.1371/journal.pgen.1006827. eCollection 2017 May.

Arabidopsis RAD51, RAD51C and XRCC3 proteins form a complex and facilitate RAD51 localization on chromosomes for meiotic recombination.

Author information

State Key Laboratory of Genetic Engineering and Collaborative Innovation Center of Genetics and Development, Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China.
Institute of Banana and Plantain, Chinese Academy of Tropic Agriculture Science, Haikou, Hainan province, China.
Department of Biology and the Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America.
Center for Evolutionary Biology, Institutes of Biomedical Sciences, School of Life Sciences, Fudan University, Shanghai, China.


Meiotic recombination is required for proper homologous chromosome segregation in plants and other eukaryotes. The eukaryotic RAD51 gene family has seven ancient paralogs with important roles in mitotic and meiotic recombination. Mutations in mammalian RAD51 homologs RAD51C and XRCC3 lead to embryonic lethality. In the model plant Arabidopsis thaliana, RAD51C and XRCC3 homologs are not essential for vegetative development but are each required for somatic and meiotic recombination, but the mechanism of RAD51C and XRCC3 in meiotic recombination is unclear. The non-lethal Arabidopsis rad51c and xrcc3 null mutants provide an opportunity to study their meiotic functions. Here, we show that AtRAD51C and AtXRCC3 are components of the RAD51-dependent meiotic recombination pathway and required for normal AtRAD51 localization on meiotic chromosomes. In addition, AtRAD51C interacts with both AtRAD51 and AtXRCC3 in vitro and in vivo, suggesting that these proteins form a complex (es). Comparison of AtRAD51 foci in meiocytes from atrad51, atrad51c, and atxrcc3 single, double and triple heterozygous mutants further supports an interaction between AtRAD51C and AtXRCC3 that enhances AtRAD51 localization. Moreover, atrad51c-/+ atxrcc3-/+ double and atrad51-/+ atrad51c-/+ atxrcc3-/+ triple heterozygous mutants have defects in meiotic recombination, suggesting the role of the AtRAD51C-AtXRCC3 complex in meiotic recombination is in part AtRAD51-dependent. Together, our results support a model in which direct interactions between the RAD51C-XRCC3 complex and RAD51 facilitate RAD51 localization on meiotic chromosomes and RAD51-dependent meiotic recombination. Finally, we hypothesize that maintenance of RAD51 function facilitated by the RAD51C-XRCC3 complex could be highly conserved in eukaryotes.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center