Identification of the Pharmacophore of the CC Chemokine-binding Proteins Evasin-1 and -4 Using Phage Display

Abstract

Background:The selectivity profiles of the closely related chemokine-binding proteins Evasin-1 and -4 differ. Results: Using phage display, we identified the N-terminal region of Evasin-4 as key for the interaction with CC chemokines. Conclusion: Evasin-1 and -4 use different domains for target binding. Significance: Phage display allowed rapid insight into their different selectivities, which could aid rational design of inhibitory proteins.

Regulation of Chemokine- Receptor Interactions and Functions

“…These observations are in line with the idea that specific CD26 inhibition protects CXCL10 from inactivation in vivo. Indeed, in contrast to what is the case in our in vitro experiments, 120 Books MDPI soluble CD26 and membrane-bound CD26 on non-lymphoid cells such as certain endothelial cells, fibroblasts and epithelial cells is present in vivo in addition to T cell-associated membrane-bound CD26 [83]. Therefore, in in vitro chemotaxis experiments, CXCL10 was not hindered by soluble CD26, but could only be inactivated by CD26 when it directly contacted the membrane-bound enzyme.…”

“…Y13 is a residue in the N-loop that is known to be important for receptor signaling and a target for ONOO − . Nitration alters the pK a making tyrosine residues more acidic, increases the mass of the protein by 45 Da per residue nitrated [54], and is also likely to cause some steric hindrance through increasing the surface area of tyrosine's phenolic ring [120]. The nitration of tyrosine also affects its hydrophobicity, although there are conflicting reports in the literature as to whether this makes the residue more hydrophilic [70] or hydrophobic [120].…”

“…CCL2 underdoes nitration in response to macrophage activation [118] and nitrated CCL2 has reduced monocyte-binding and chemotactic function [118,119]. Similarly nitration of CCL5 attenuates its chemotactic activity [120]. In addition to direct modification of chemokine structure and activity, nitration or nitrosylation (addition of NO rather than NO 2 ) of other proteins can indirectly influence chemokine or receptor function.…”

“…Nitration alters the pK a making tyrosine residues more acidic, increases the mass of the protein by 45 Da per residue nitrated [54], and is also likely to cause some steric hindrance through increasing the surface area of tyrosine's phenolic ring [120]. The nitration of tyrosine also affects its hydrophobicity, although there are conflicting reports in the literature as to whether this makes the residue more hydrophilic [70] or hydrophobic [120]. It is possible that the hydrophobicity of tyrosine is important in the function of CXCL8 in particular, as a Y13L mutant (which maintains hydrophobicity) showed similar if not slightly increased activity when compared to the wild type [121], but Y13E (hydrophilic) and Y13T (neutral) mutants both showed a decrease in receptor affinity [122].…”

Produção e caracterização funcional de uma nova evasina putativa de carrapatos Rhipicephalus microplus

“…Embora a produção desta proteína não tenha surtido resultado positivo no sistema eucarioto (P. pastoris) durante o desenvolvimento deste trabalho, a produção da mesma em sistemas que permitam modificações pós-traducionais pode ser indicada para estudos posteriores de estrutura e função anti-inflamatória, visto que modificações na configuração estrutural dada pela ocorrência de pontes dissulfeto parece ser essencial para a adequada atividade de proteínas similares, como a Evasin-1 e Evasin-4 de carrapatos R. sanguineus (DIAS et al, 2009;BONVIN et al, 2014).…”