CXCL12 and Its Isoforms: Different Roles in Pancreatic Cancer?

Figure 2

CXCL12 sequence. (a) The CXCL12 immature form, the propeptide, which includes the 21 amino acids at the N-terminal end, that will be removed. (b) The mature CXCL12 form has undergone a proteolytic cut of 21 amino acids at the N-terminal end. The first 8 amino acids of the mature CXCL12 allow the receptor interaction; in particular, the first two, lysine and proline, activate the CXCR4 receptor while the other six are used for the receptor binding. Also, the “RFFESH” sequence allows the ligand-receptor binding. (c) Representations of all CXCL12 isoforms are reported. They all have the same starting sequence, but each one differs from the others in the terminal region length.