44 45 Page 4 of 50 4 HIGHLIGHTS 45  Models of conserved 5' and 3' betacoronavirus cis-acting RNA secondary structures are 46 presented 47  The 5' cis-acting sequences required for coronavirus replication extend into the first open reading 48 frame 49  All 3' cis-acting sequences required for coronavirus replication are contained in the 3'UTR 50  A putative molecular switch is present in the coronavirus 3'UTR 51  Proteins interacting with these cis-acting regions are reviewed 52 53