Is Required for Accurate Double-Strand Break Repair During Maize Male Meiosis.

RAD17, a replication factor C (RFC)-like DNA damage sensor protein, is involved in DNA checkpoint control and required for both meiosis and mitosis in yeast and mammals. In plant, the meiotic function of was only reported in rice so far. Here, we identified and characterized the homolog in maize. The mutants exhibited normal vegetative growth but male was partially sterile. In pollen mother cells, non-homologous chromosome entanglement and chromosome fragmentation were frequently observed. Immunofluorescence analysis manifested that DSB formation occurred as normal and the loading pattern of RAD51 signals was similar to wild-type at the early stage of prophase I in the mutants. The localization of the axial element ASY1 was normal, while the assembly of the central element ZYP1 was severely disrupted in meiocytes. Surprisingly, no obvious defect in female sterility was observed in mutants. Taken together, our results suggest that is involved in DSB repair likely by promoting synaptonemal complex assembly in maize male meiosis. These phenomena highlight a high extent of divergence from its counterpart in rice, indicating that the dysfunction can result in a drastic dissimilarity in meiotic outcome in different plant species.