The domain within your query sequence starts at position 517 and ends at position 599; the E-value for the RPT_2 domain shown below is 2.49e-5.

EWGKLHVAILEREKQLRSEFERLECLQRIVSKLQMEAGLCEEQLNQADALLQSDIRLLAS
GKVAQRAGEVERDLDKADGMIRL

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