FIG. 3.

Diagram of PCR amplification of the p28 gene. The dark boxes represent noncoding DNA sequences bordering the p28 gene. The shaded box and the open box represent the DNA sequence encoding the leader peptide and the sequence encoding the mature p28, respectively. The numbers on the top of the gene indicate the nucleotide positions in base pairs. Arrows indicate the directions of primers. The start point of each primer corresponds to the number at the end of the arrow and on the top of the p28 gene.