Calpain-mediated cleavages in the talin rod domain. The 4 PDB structures shown depict helices as pipes and are arranged in sequential order. The N-terminus of a calpain cleavage is shown in red and the C-terminus in blue. Below each image is a schematic in which the helices are depicted as rectangles and their location in the talin rod is indicated. VBSs are shown in green, and calpain cleavage sites are indicated with red arrows. Structure 1XWX is a model that encompasses helices 1 to 12. The 13th helix is borrowed from NMR structure 2L7A. 2X0C covers helices 28 to 36, but only 28 to 30 and 35 to 36 are shown. The final 10-helix bundle is 3DYJ, depicting talin rod helices 47 to 56. Images were made using Chimera.