We have tested conditions for the labeling and
tailing the 3′-end of RNAs with yeast poly(A) polymerase.
Conditions were optimized for addition of NTP, dNTP, or
ddNTP nucleotides to RNA. ATP, GTP, and UTP were useful
for adding homopolymer tracts of various lengths. The nonradioactive
nucleotides biotin-N6-ATP and digoxigenin-11-UTP
also were used efficiently.