Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor

Aishwarya Ravindran, Kirti V. Sawant, Jose Sarmiento, Javier Navarro, Krishna Rajarathnam

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The CXCL1/CXCR2 axis plays a crucial role in recruiting neutrophils in response to microbial infection and tissue injury, and dysfunction in this process has been implicated in various inflammatory diseases. Chemokines exist as monomers and dimers, and compelling evidence now exists that both forms regulate in vivo function. Therefore, knowledge of the receptor activities of both CXCL1 monomer and dimer is essential to describe the molecular mechanisms by which they orchestrate neutrophil function. The monomer-dimer equilibrium constant (∼20 μm) and the CXCR2 binding constant (1 nM) indicate that WT CXCL1 is active as a monomer. To characterize dimer activity, we generated a trapped dimer by introducing a disulfide across the dimer interface. This disulfide-linked CXCL1 dimer binds CXCR2 with nanomolar affinity and shows potent agonist activity in various cellular assays. We also compared the receptor binding mechanism of this dimer with that of a CXCL1 monomer, generated by deleting the C-terminal residues that stabilize the dimer interface. We observe that the binding interactions of the dimer and monomer to the CXCR2 N-termi-nal domain, which plays an important role in determining affinity and activity, are essentially conserved. The potent activity of the CXCL1 dimer is novel: dimers of the CC chemokines CCL2 and CCL4 are inactive, and the dimer of the CXC chemokine CXCL8 (which is closely related to CXCL1) is marginally active for CXCR1 but shows variable activity for CXCR2. We conclude that large differences in dimer activity among different chemo-kine-receptor pairs have evolved for fine-tuned leukocyte function.

Original languageEnglish (US)
Pages (from-to)12244-12252
Number of pages9
JournalJournal of Biological Chemistry
Volume288
Issue number17
DOIs
StatePublished - Apr 26 2013

Fingerprint

Chemokine CXCL1
Interleukin-8B Receptors
Disulfides
Dimers
Neutrophils
Chemokine CCL4
CXC Chemokines
CC Chemokines
Chemokine CCL2
Interleukin-8
Chemokines
Leukocytes
Monomers
Wounds and Injuries
Infection

ASJC Scopus subject areas

  • Biochemistry
  • Cell Biology
  • Molecular Biology

Cite this

Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor. / Ravindran, Aishwarya; Sawant, Kirti V.; Sarmiento, Jose; Navarro, Javier; Rajarathnam, Krishna.

In: Journal of Biological Chemistry, Vol. 288, No. 17, 26.04.2013, p. 12244-12252.

Research output: Contribution to journalArticle

Ravindran, Aishwarya ; Sawant, Kirti V. ; Sarmiento, Jose ; Navarro, Javier ; Rajarathnam, Krishna. / Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor. In: Journal of Biological Chemistry. 2013 ; Vol. 288, No. 17. pp. 12244-12252.
@article{8d5f893ff676436e9e3d13c0bffbd81f,
title = "Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor",
abstract = "The CXCL1/CXCR2 axis plays a crucial role in recruiting neutrophils in response to microbial infection and tissue injury, and dysfunction in this process has been implicated in various inflammatory diseases. Chemokines exist as monomers and dimers, and compelling evidence now exists that both forms regulate in vivo function. Therefore, knowledge of the receptor activities of both CXCL1 monomer and dimer is essential to describe the molecular mechanisms by which they orchestrate neutrophil function. The monomer-dimer equilibrium constant (∼20 μm) and the CXCR2 binding constant (1 nM) indicate that WT CXCL1 is active as a monomer. To characterize dimer activity, we generated a trapped dimer by introducing a disulfide across the dimer interface. This disulfide-linked CXCL1 dimer binds CXCR2 with nanomolar affinity and shows potent agonist activity in various cellular assays. We also compared the receptor binding mechanism of this dimer with that of a CXCL1 monomer, generated by deleting the C-terminal residues that stabilize the dimer interface. We observe that the binding interactions of the dimer and monomer to the CXCR2 N-termi-nal domain, which plays an important role in determining affinity and activity, are essentially conserved. The potent activity of the CXCL1 dimer is novel: dimers of the CC chemokines CCL2 and CCL4 are inactive, and the dimer of the CXC chemokine CXCL8 (which is closely related to CXCL1) is marginally active for CXCR1 but shows variable activity for CXCR2. We conclude that large differences in dimer activity among different chemo-kine-receptor pairs have evolved for fine-tuned leukocyte function.",
author = "Aishwarya Ravindran and Sawant, {Kirti V.} and Jose Sarmiento and Javier Navarro and Krishna Rajarathnam",
year = "2013",
month = "4",
day = "26",
doi = "10.1074/jbc.M112.443762",
language = "English (US)",
volume = "288",
pages = "12244--12252",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "17",

}

TY - JOUR

T1 - Chemokine CXCL1 dimer is a potent agonist for the CXCR2 receptor

AU - Ravindran, Aishwarya

AU - Sawant, Kirti V.

AU - Sarmiento, Jose

AU - Navarro, Javier

AU - Rajarathnam, Krishna

PY - 2013/4/26

Y1 - 2013/4/26

N2 - The CXCL1/CXCR2 axis plays a crucial role in recruiting neutrophils in response to microbial infection and tissue injury, and dysfunction in this process has been implicated in various inflammatory diseases. Chemokines exist as monomers and dimers, and compelling evidence now exists that both forms regulate in vivo function. Therefore, knowledge of the receptor activities of both CXCL1 monomer and dimer is essential to describe the molecular mechanisms by which they orchestrate neutrophil function. The monomer-dimer equilibrium constant (∼20 μm) and the CXCR2 binding constant (1 nM) indicate that WT CXCL1 is active as a monomer. To characterize dimer activity, we generated a trapped dimer by introducing a disulfide across the dimer interface. This disulfide-linked CXCL1 dimer binds CXCR2 with nanomolar affinity and shows potent agonist activity in various cellular assays. We also compared the receptor binding mechanism of this dimer with that of a CXCL1 monomer, generated by deleting the C-terminal residues that stabilize the dimer interface. We observe that the binding interactions of the dimer and monomer to the CXCR2 N-termi-nal domain, which plays an important role in determining affinity and activity, are essentially conserved. The potent activity of the CXCL1 dimer is novel: dimers of the CC chemokines CCL2 and CCL4 are inactive, and the dimer of the CXC chemokine CXCL8 (which is closely related to CXCL1) is marginally active for CXCR1 but shows variable activity for CXCR2. We conclude that large differences in dimer activity among different chemo-kine-receptor pairs have evolved for fine-tuned leukocyte function.

AB - The CXCL1/CXCR2 axis plays a crucial role in recruiting neutrophils in response to microbial infection and tissue injury, and dysfunction in this process has been implicated in various inflammatory diseases. Chemokines exist as monomers and dimers, and compelling evidence now exists that both forms regulate in vivo function. Therefore, knowledge of the receptor activities of both CXCL1 monomer and dimer is essential to describe the molecular mechanisms by which they orchestrate neutrophil function. The monomer-dimer equilibrium constant (∼20 μm) and the CXCR2 binding constant (1 nM) indicate that WT CXCL1 is active as a monomer. To characterize dimer activity, we generated a trapped dimer by introducing a disulfide across the dimer interface. This disulfide-linked CXCL1 dimer binds CXCR2 with nanomolar affinity and shows potent agonist activity in various cellular assays. We also compared the receptor binding mechanism of this dimer with that of a CXCL1 monomer, generated by deleting the C-terminal residues that stabilize the dimer interface. We observe that the binding interactions of the dimer and monomer to the CXCR2 N-termi-nal domain, which plays an important role in determining affinity and activity, are essentially conserved. The potent activity of the CXCL1 dimer is novel: dimers of the CC chemokines CCL2 and CCL4 are inactive, and the dimer of the CXC chemokine CXCL8 (which is closely related to CXCL1) is marginally active for CXCR1 but shows variable activity for CXCR2. We conclude that large differences in dimer activity among different chemo-kine-receptor pairs have evolved for fine-tuned leukocyte function.

UR - http://www.scopus.com/inward/record.url?scp=84876919853&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84876919853&partnerID=8YFLogxK

U2 - 10.1074/jbc.M112.443762

DO - 10.1074/jbc.M112.443762

M3 - Article

C2 - 23479735

AN - SCOPUS:84876919853

VL - 288

SP - 12244

EP - 12252

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 17

ER -