Figure 2.

Amino Acid Sequences of Exendin-4, GLP-1, GIP, and Their Derivatives. Exendin-4 and its derivatives are depicted in green, while GLP-1 and its derivatives are represented in red. GLP-1 is conserved across mammalian species. Human GIP and some mammalian (porcine and bovine) GIP variants are shown in blue. The amino acids of the derivatives that differ from their backbone sequences are highlighted in black and underlined. The amino acids of bovine and porcine GIP that are not homologous to human GIP, as well as the amino acids of Heloderma Suspectum GLP-1 that are not homologous to human GLP-1, are also underlined. In NNC0090-2746 and tirzepatide, amino acids shared by both GIP and GLP-1 are displayed in violet, those unique to GIP are shown in blue, those exclusive to GLP-1 are shown in red, and those specific to exendin-4 are displayed in green, while those not identical to GIP, GLP-1 or exendin-4 are depicted in black and underlined. The acylated lysine residues in liraglutide, semaglutide, NNC0090-2746, and tirzepatide are indicated by yellow-filled circles. Seven amino acids conserved in all peptides are highlighted in the boxes.