Solution to PS 1 #5
The 32P appears only at the 5' end of the mRNA molecules that
have A as the first residue. It does not appear in the other residues
because the b-Phosphoryl group is eliminated
as PPi when nucleoside triphosphates are added to the 3' end of the
growing RNA Chain. When the mRNA is capped, the 32P is retained
since only the g-phosphoryl group of the initial
residue is removed when the cap is formed. The b-phosphoryl
group, which contains the label is retained and receves the GMP group from
GTP.
Return to Problem Set #1