Alternative Splicing

Alternative exon combinations can lead to different proteins

The primary hnRNA transcript includes both exon- & intron-equvialent sequences. The exon-equivalents (numbered) may correspond to functional domains of the protein, for example, DNA-binding regions or enzymatic activities. By removing one or more exon-equivalent regions along with the intron-equivalents, different proteins with different functions can be produced.

Alternative splicing may explain why genomes can get along with far fewer protein-coding regions than expected.