when and what end does the tailing of hnRNA take place?
During trascription of eukaryotes, to get rid of the introns which do not particpate in coding, tailing is done(along with capping.)
Capping − methyl guanosine triphosphate is added to the 5′ end of hnRNA.
Tailing − adenylate residues are added to the 3′ end of hnRNA.
then it is ready for translation.
hope that answered your question!