The relationship between coding sequences and function in some heme binding proteins

Summary

It is known that globin genes contain three exons with the middle exon coding for a four-helical supersecondary structure responsible for heme binding. Since this portion of the globin peptide chain can be structurally superimposed onto the cytochromec and cytochromeb ₅ chains (Argos and Rossmann 1979), it can be inferred that the cytochromec gene will contain only one coding sequence while the cytochromeb ₅ gene will be composed of three exons as found in the globin gene.