Fig. 7: The frameshift mutation in C12ORF40/REDIC1 largely impairs its ability to bind branched recombination intermediates.
From: A novel recombination protein C12ORF40/REDIC1 is required for meiotic crossover formation
a EMSA with purified REDIC1 protein (WT) and the indicated DNA substrates. The experiments were repeated three times with similar results. For each group, 100 nmol of 5-FAM-labeled DNA substrates were used. b EMSA with purified REDIC1 N-fragment (1–228 aa), M-fragment (229–438 aa), or C-fragment (439–652 aa) and D-loop. The experiments were repeated twice with similar results. For each group, 100 nmol of 5-FAM-labeled DNA substrates were used. c EMSA with purified REDIC1 N-fragment (1–228 aa) or mutant (p.Met78Ilefs*2) and D-loop. d 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.
