The domain within your query sequence starts at position 520 and ends at position 571; the E-value for the RPT_1 domain shown below is 3.18e-18.

GAPGNRGFPGSDGLPGPKGAQGERGPVGSSGPKGGQGDPGRPGEPGLPGARG

This is a significant internal repeat in the query protein sequence, as detected by the Prospero program.