Figure 5.

(A) Overview of the proposed signaling pathways activated by COL(I). COL(I) binding to the integrin α2β1 receptor triggers the activation of Src kinase [5,6] (which was not detected in this study), leading to the downstream activation of calumenin (CALU) [90]. Heat shock protein beta 1 (HSPB1) and CALU are involved in the formation of filopodia and subsequent endothelial cell migration [86,88,90,93]. Phosphorylated calnexin (CANX) aids in the folding of N-linked glycoproteins, which later move to the cell membrane and affect cell adhesion and migration [91,92]. (B) Peptide 1 likely blocks the interaction of COL(I) with integrin α2β1, thereby preventing the activation of the signaling cascade outlined in panel A. Abbreviations: VIM: vimentin, CALU: calumenin, HSPB1: heat shock protein beta 1, DBN1: drebrin.