Dataset Information

Semisynthesis of an evasin from tick saliva reveals a critical role of tyrosine sulfation for chemokine binding and inhibition.

ABSTRACT: Blood-feeding arthropods produce antiinflammatory salivary proteins called evasins that function through inhibition of chemokine-receptor signaling in the host. Herein, we show that the evasin ACA-01 from the Amblyomma cajennense tick can be posttranslationally sulfated at two tyrosine residues, albeit as a mixture of sulfated variants. Homogenously sulfated variants of the proteins were efficiently assembled via a semisynthetic native chemical ligation strategy. Sulfation significantly improved the binding affinity of ACA-01 for a range of proinflammatory chemokines and enhanced the ability of ACA-01 to inhibit chemokine signaling through cognate receptors. Comparisons of evasin sequences and structural data suggest that tyrosine sulfation serves as a receptor mimetic strategy for recognizing and suppressing the proinflammatory activity of a wide variety of mammalian chemokines. As such, the incorporation of this posttranslational modification (PTM) or mimics thereof into evasins may provide a strategy to optimize tick salivary proteins for antiinflammatory applications.

SUBMITTER: Franck C

PROVIDER: S-EPMC7293604 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Semisynthesis of an evasin from tick saliva reveals a critical role of tyrosine sulfation for chemokine binding and inhibition.

Franck Charlotte C Foster Simon R SR Johansen-Leete Jason J Chowdhury Sayeeda S Cielesh Michelle M Bhusal Ram Prasad RP Mackay Joel P JP Larance Mark M Stone Martin J MJ Payne Richard J RJ

Proceedings of the National Academy of Sciences of the United States of America 20200527 23

Blood-feeding arthropods produce antiinflammatory salivary proteins called evasins that function through inhibition of chemokine-receptor signaling in the host. Herein, we show that the evasin ACA-01 from the <i>Amblyomma cajennense</i> tick can be posttranslationally sulfated at two tyrosine residues, albeit as a mixture of sulfated variants. Homogenously sulfated variants of the proteins were efficiently assembled via a semisynthetic native chemical ligation strategy. Sulfation significantly i ...[more]

PMID: 32461364

Similar Datasets

Project description:BackgroundChemokines are a subset of cytokines responsible for controlling the cellular migration of inflammatory cells through interaction with seven transmembrane G protein-coupled receptors. The blocking of a chemokine-receptor interaction results in a reduced inflammatory response, and represents a possible anti-inflammatory strategy, a strategy that is already employed by some virus and parasites. Anti-chemokine activity has been described in the extracts of tick salivary glands, and we have recently described the cloning and characterization of such chemokine binding proteins from the salivary glands, which we have named Evasins.Methodology/principal findingsWe have solved the structure of Evasin-1, a very small and highly selective chemokine-binding protein, by x-ray crystallography and report that the structure is novel, with no obvious similarity to the previously described structures of viral chemokine binding proteins. Moreover it does not possess a known fold. We have also solved the structure of the complex of Evasin-1 and its high affinity ligand, CCL3. The complex is a 1:1 heterodimer in which the N-terminal region of CCL3 forms numerous contacts with Evasin-1, including prominent pi-pi interactions between residues Trp89 and Phe14 of the binding protein and Phe29 and Phe13 of the chemokine.Conclusions/significanceHowever, these interactions do not appear to be crucial for the selectivity of the binding protein, since these residues are found in CCL5, which is not a ligand for Evasin-1. The selectivity of the interaction would appear to lie in the N-terminal residues of the chemokine, which form the "address" whereas the hydrophobic interactions in the rest of the complex would serve primarily to stabilize the complex. A thorough understanding of the binding mode of this small protein, and its other family members, could be very informative in the design of potent neutralizing molecules of pro-inflammatory mediators of the immune system, such as chemokines.

Dataset Information

Semisynthesis of an evasin from tick saliva reveals a critical role of tyrosine sulfation for chemokine binding and inhibition.

Publications

Semisynthesis of an evasin from tick saliva reveals a critical role of tyrosine sulfation for chemokine binding and inhibition.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets