MC, please see the attached; this virus has a polyphasic cleavage site of 5 arginines (furin substrate), and two are encoded by CGG.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC391999/pdf/pnas00622-0148.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC391999/pdf/pnas00622-0148.pdf