We have tested the functioning of the human c-myc polyadenylation signal in Saccharomyces cerevisiae. A DNA fragment containing the two AATAAA polyadenylation signals of the c-myc gene was inserted into a plasmid designed for the in-vivo testing of polyadenylation signals in yeast. The c-myc fragment had a partial capacity for directing mRNA 3'-end formation in yeast. The 3'-endpoints were 50-100 bp distant from the mRNA 3'-ends mapped in humans. This human DNA fragment is therefore unspecifically functional in yeast, indicating that other sequence elements than the human polyadenylation signal, AATAAA, are necessary for 3'-end formation.