Liu and Leibowitz identified a potential base pairing between nucleotides 8-749 24 in the MHV 5' UTR SL1 and two discontinuous sequences in the 3'UTR, nts 1-6 and 218-228 750 (note that the 3'UTR sequences are numbered with position 1 corresponding to the first 751 nucleotide 5' of the poly (A) tail).