Fig. 3.
mi mRNA starting site (primer extension experiments) in mast cells. An oligonucleotide 5′ GTT TTC CAG GTG GGT CTG CAG 3′ from the putative common part of the heart and melanocyte mi mRNA was end-labeled and then the mRNA was precipitated and reverse transcribed as described in Materials and Methods. The samples were then loaded together with a puc18/Msp I-restricted [32P]-labeled size marker on a 4% acrylamide 7 mol/L urea denaturing gel. One representative experiment of two performed is shown.