TY - JOUR
T1 - Effects of the RGD loop and C-terminus of rhodostomin on regulating integrin αIIbβ3 recognition
AU - Chang, Yao Tsung
AU - Shiu, Jia Hau
AU - Huang, Chun Hao
AU - Chen, Yi Chun
AU - Chen, Chiu Yueh
AU - Chang, Yung Sheng
AU - Chuang, Woei Jer
N1 - Publisher Copyright:
© 2017 Chang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2017/4
Y1 - 2017/4
N2 - Rhodostomin (Rho) is a medium disintegrin containing a 48PRGDMP motif. We here showed that Rho proteins with P48A, M52W, and P53N mutations can selectively inhibit integrin αIIbβ3. To study the roles of the RGD loop and C-terminal region in disintegrins, we expressed Rho 48PRGDMP and 48ARGDWN mutants in Pichia pastoris containing65P, 65PR, 65PRYH, 65PRNGLYG, and 65PRNPWNG C-terminal sequences. The effect of C-terminal region on their integrin binding affinities was αIIbβ3 > αvβ3 o>α5β1, and the48ARGDWN- 48ARGDWN-56PRNPWNG protein was the most selective integrin αIIbβ3 mutant. The48ARGDWN- 48ARGDWN-56PRYH, 48ARGDWN- 48ARGDWN-56PRNGLYG, and 48ARGDWN- 48ARGDWN-56PRNPWNG mutants had similar activities in inhibiting platelet aggregation and the binding of fibrinogen to platelet. In contrast, 48ARGDWN-56PRYH and 48ARGDWN- 48ARGDWN-56PRNGLYG exhibited 2.9- and 3.0-fold decreases in inhibiting cell adhesion in comparison with that of48ARGDWN- 48ARGDWN-56PRNPWNG. Based on the results of cell adhesion, platelet aggregation and the binding of fibrinogen to platelet inhibited by ARGDWN mutants, integrin αIIbβ3 bound differently to immobilized and soluble fibrinogen. NMR structural analyses of48ARGDWN- 48ARGDWN-56PRYH, 48ARGDWN- 48ARGDWN-56PRNGLYG, and 48ARGDWN- 48ARGDWN-56PRNPWNG mutants demonstrated that their C-terminal regions interacted with the RGD loop. In particular, the W52 sidechain of 48ARGDWN interacted with H68 of 65PRYH, L69 of 65PRNGLYG, and N70 of 65PRNPWNG, respectively. The docking of the 48ARGDWN- 48ARGDWN-56PRNPWNG mutant into integrin αIIbβ3 showed that the N70 residue formed hydrogen bonds with the αIIb D159 residue, and the W69 residue formed cation-? interaction with the β3 K125 residue. These results provide the first structural evidence that the interactions between the RGD loop and C-terminus of medium disintegrins depend on their amino acid sequences, resulting in their functional differences in the binding and selectivity of integrins.
AB - Rhodostomin (Rho) is a medium disintegrin containing a 48PRGDMP motif. We here showed that Rho proteins with P48A, M52W, and P53N mutations can selectively inhibit integrin αIIbβ3. To study the roles of the RGD loop and C-terminal region in disintegrins, we expressed Rho 48PRGDMP and 48ARGDWN mutants in Pichia pastoris containing65P, 65PR, 65PRYH, 65PRNGLYG, and 65PRNPWNG C-terminal sequences. The effect of C-terminal region on their integrin binding affinities was αIIbβ3 > αvβ3 o>α5β1, and the48ARGDWN- 48ARGDWN-56PRNPWNG protein was the most selective integrin αIIbβ3 mutant. The48ARGDWN- 48ARGDWN-56PRYH, 48ARGDWN- 48ARGDWN-56PRNGLYG, and 48ARGDWN- 48ARGDWN-56PRNPWNG mutants had similar activities in inhibiting platelet aggregation and the binding of fibrinogen to platelet. In contrast, 48ARGDWN-56PRYH and 48ARGDWN- 48ARGDWN-56PRNGLYG exhibited 2.9- and 3.0-fold decreases in inhibiting cell adhesion in comparison with that of48ARGDWN- 48ARGDWN-56PRNPWNG. Based on the results of cell adhesion, platelet aggregation and the binding of fibrinogen to platelet inhibited by ARGDWN mutants, integrin αIIbβ3 bound differently to immobilized and soluble fibrinogen. NMR structural analyses of48ARGDWN- 48ARGDWN-56PRYH, 48ARGDWN- 48ARGDWN-56PRNGLYG, and 48ARGDWN- 48ARGDWN-56PRNPWNG mutants demonstrated that their C-terminal regions interacted with the RGD loop. In particular, the W52 sidechain of 48ARGDWN interacted with H68 of 65PRYH, L69 of 65PRNGLYG, and N70 of 65PRNPWNG, respectively. The docking of the 48ARGDWN- 48ARGDWN-56PRNPWNG mutant into integrin αIIbβ3 showed that the N70 residue formed hydrogen bonds with the αIIb D159 residue, and the W69 residue formed cation-? interaction with the β3 K125 residue. These results provide the first structural evidence that the interactions between the RGD loop and C-terminus of medium disintegrins depend on their amino acid sequences, resulting in their functional differences in the binding and selectivity of integrins.
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U2 - 10.1371/journal.pone.0175321
DO - 10.1371/journal.pone.0175321
M3 - Article
C2 - 28399159
AN - SCOPUS:85017524657
SN - 1932-6203
VL - 12
JO - PloS one
JF - PloS one
IS - 4
M1 - e0175321
ER -