Figure 1. RT-PCR analysis of mouse amelogenin with the use of cDNA derived from a mouse tooth cDNA library and mouse immortalized dental cell lines. Two different RNA transcripts have been isolated and sequenced within the exons 2–9 mouse AMELX region (A). Lane 1, DNA markers; Lane 2, negative control; Lane 3, mouse tooth cDNA library; Lane 4, odontoblast cell line (MO6-G3); Lane 5, ameloblast cell line (MEOE-3M). DNA sequence analysis of mouse AMELX exon 8 and exon 9 and their splice variants (B). DNA sequence alignment of the mouse and rat amelogenin cDNA sequence for exons 8 & 9 showed a 93% homology between species (B). Both mouse and rat sequences contain a stop codon at position 74 (B; black rectangle). Protein prediction of the exons 8 and 9 region showed 87% homology with the predicted rat protein (C). The mouse-predicted exons 8 and 9 encoded protein sequence differs in 3 amino acids from the predicted rat protein sequence (C; black circles).