Fig. 4.

Alignment of the four human CDK5RAP2 isoforms. The human CDK5RAP2 gene comprises 38 exons, and isoform Q96SN8-1 contains all of these 38 exons. Three further isoforms produced by alternative splicing have been reported so far: (1) isoform Q96SN8-2 missing exon 19 (aa 702–733); (2) isoform Q96SN8-3 missing exon 23 (aa 1009–1049); and (3) isoform Q96SN8-4 lacking exon 32 (aa 1576–1654). The in vivo existence of these isoforms in humans is confirmed by GenBank EST evidence. None of the functional motifs identified so far (see Fig. 2) are encoded by the alternatively spliced exons of the CDK5RAP2 isoforms. Similarly to the situation in humans, comparable isoforms also exist in other organisms such as mice and rats, and have been confirmed by GenBank in silico analysis. In mice and rats, the isoform 1 is not represented in the GenBank; however, a search of GenBank sequences shows the presence of the respective homologous exon on the genomic level