This part encodes a replication protein
Replication proteins are, well, proteins involved in replication. Most of the ones involved in this project are DNA binding proteins of sorts that bind to a specific DNA cis element and initiate replication in cis. In other words, they replicate the DNA that contains the cis element.
Different replication protein coding parts are needed in different flavors, so take special note of what type this one should be. Replication proteins are often toxic to E. coli, so you may have some difficulty making this part. Make careful note in your notebook about the size distribution of colonies you get on your plates and the ratio of red to white colonies.