Residual Participation and Thermodynamic Stability Due to Molecular Interactions in IL11, IL11Rα and Gp130 from Homo sapiens: An In Silico Outlook for IL11 as a Therapeutic Remedy

Abstract

An extensive problem after chemotherapy is “thrombocytopenia”. It has been known (through protein assays only) to recover after the interaction of IL11 protein with IL11Rα and gp130. Among the three proteins, gp130 is known as a predominant player as it interacts with several other proteins of IL6 cytokine family. This study focused to the structure and interaction pattern of the associated proteins through protein–protein docking and molecular dynamics simulation studies. The detailed stability parameters and conformational fluctuations due to interaction were analyzed. ΔG values and net solvent accessibility showed spontaneous interaction of gp130 with stronger residual participation. Conformational fluctuations in gp130 to adopt a higher percentage of residues in helical and β-sheets make the protein stable with firmer interaction. All outcomes showed a P-value of less than 5% (statistically significant). Mainly, ionic–ionic, aromatic–aromatic and cation–pi interactions were observed to be predominant. Among 5 ionic interactions, (from gp130) three were by Lys551 and Asp552 with IL11Rα protein, respectively. The other two ionic interactions were between IL11 and its receptor. Each of the aromatic interactions was formed mainly by Tyr95 (gp130 protein) while phenylalanine played an important role in cation–pi interactions. Residues from Ig-like domain of IL11Rα were seen to interact directly. Altogether, a positive environment with cavity was formed to strongly accommodate IL11 and its receptor protein. This leads to infer IL11 as a therapeutic remedy for replenishing the loss of blood platelets. This study through detailed molecular and residual exposure instigates effective drug discovery and future studies of mutational impacts.