DETERMINATION OF THE POLY(A) TAIL LENGTHS OF A SINGLE MESSENGER-RNA SPECIES IN TOTAL HEPATIC RNA

Poly(A) tail length is important in the stability and translation of m RNA. We describe procedures for the rapid and reproducible analysis of poly(A) tail length of a single mRNA species contained in a sample of total hepatic RNA. A short 3' fragment of a specific mRNA is prepared by RNase H digestion of the targeted mRNA region annealed to a short DNA oligonucleotide. The length of the poly(A) rail of the 3' fragment is then determined by running the sample on a polyacrylamide gel, by electrophoretic transfer by probing with a radiolabeled cDNA and by co mparing the size of the detected region with a specific RNA ladder or a DNA ladder.