I have heard about 'reverse' blast searches, such as using RPS-BLAST. According to the website,
RPS-BLAST (Reverse PSI-BLAST) searches a query sequence against a database of profiles. This is the opposite of PSI-BLAST that searches a profile against a database of sequences, hence the 'Reverse'.
I still don't understand exactly what is the meaning and purpose of this... like what would be a good use case?