The domain within your query sequence starts at position 378 and ends at position 466; the E-value for the RPT_2 domain shown below is 2.63e-8.

ASSSPPQGTSETPASNSPPQGTSETPGFSSPPQVTTATLVSSSPPQVTSETPASSSPTQV
TSETPASSSPTQVTSDTPASNSPPQGTSD

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