In eukaryotic cells, importin o is an essential carrier for transport proteins into nucleus.We identified a conserved importin o gene PslMPA1 in Phytophthora sojae which comprised a flexible N-terminal IBB (importin β binding) domain and a tandem series of 10 armadillo (ARM) repeats representing NLS binding domain in C-terminal.PslMPA1 is different expressed during the life cycle with the highest expression level in 6 hours post inoculation.