The domain within your query sequence starts at position 326 and ends at position 400; the E-value for the RPT_1 domain shown below is 2.94e-9.

MPDVKEKVAELLGKYSSGLWASALPKAFEDMYKVKFPEDALKNLASLSDVCTINYISGNT
QKAILYAKLPLPTDK

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