Speaker
Description
DMC1 recombinase is essential for meiotic homologous recombination. Recombinases, such as RAD51, can assemble on DNA to form extended nucleoprotein filaments to function in homology search and strand exchange. Surprisingly, our recent single-molecule measurements show that human DMC1 can form condensed, compact filaments on double-stranded DNA . These condensed filaments differ markedly from canonical extended filaments in their stability and ion dependence, indicating that they represent a distinct structural and functional state. For example, DMC1 condensed filaments exhibit significantly higher ssDNA-capture efficiency than the extended RAD51 ones, suggesting that this compact structure may play a role in the early steps of homologous pairing. Together, our findings provide a mechanistic framework for understanding how distinct DMC1 assemblies may contribute to homologous pairing during meiosis.
