Schematic diagram showing the proposed function of REDIC1 in meiotic recombination. Following the strand invasion, the nascent D-loop is first bound and stabilized by the MSH4–5 complex. The binding of REDIC1 not only promotes chromosome synapsis but also further stabilizes HR intermediates, allowing some DSBs to be processed into dHJs, ultimately leading to the formation of crossover. In the absence of REDIC1, some recombination intermediates are destabilized, thereby forming a reduced number of crossovers via the DSBR pathway for a few DSBs; other DSBs may form non-crossovers via the SDSA pathway or the dissolution of dHJs. In addition, the destabilization of recombination intermediates can lead to synaptic defects.
