Chemokine like receptor 1 also known as ChemR23 (Chemerin Receptor 23) is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

that in humans is encoded by the ''CMKLR1''

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

. Chemokine receptor-like 1 is a

G protein-coupled receptor G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...

for the chemoattractant adipokine

chemerin Chemerin, also known as retinoic acid receptor responder protein 2 (RARRES2), tazarotene-induced gene 2 protein (TIG2), or RAR-responsive protein TIG2 is a protein that in humans is encoded by the ''RARRES2'' gene. Function Retinoids exert b ...

and the

omega-3 fatty acid Omega−3 fatty acids, also called Omega-3 oils, ω−3 fatty acids or ''n''−3 fatty acids, are polyunsaturated fatty acids (PUFAs) characterized by the presence of a double bond, three atoms away from the terminal methyl group in their chem ...

eicosapentaenoic acid Eicosapentaenoic acid (EPA; also icosapentaenoic acid) is an omega-3 fatty acid. In physiological literature, it is given the name 20:5(n-3). It also has the trivial name timnodonic acid. In chemical structure, EPA is a carboxylic acid with a 20-c ...

-derived specialized pro-resolving molecule, resolvin E1 (see Specialized proresolving mediators#EPA-derived resolvins (i.e. RvE)). The

murine The Old World rats and mice, part of the subfamily Murinae in the family Muridae, comprise at least 519 species. Members of this subfamily are called murines. In terms of species richness, this subfamily is larger than all mammal families excep ...

receptor that shares almost 80% homology with the human receptor, is called Dez.

Tissue distribution

CMKLR1 shows wide RNA expression profile but is notably high in

plasmacytoid dendritic cells Plasmacytoid dendritic cells (pDCs) are a rare type of immune cell that are known to secrete large quantities of type 1 interferon (IFNs) in response to a viral infection. They circulate in the blood and are found in peripheral lymphoid organs. Th ...

macrophage Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cel ...

cardiomyocyte Cardiac muscle (also called heart muscle, myocardium, cardiomyocytes and cardiac myocytes) is one of three types of vertebrate muscle tissues, with the other two being skeletal muscle and smooth muscle. It is an involuntary, striated muscle that ...

adipocyte Adipocytes, also known as lipocytes and fat cells, are the cells that primarily compose adipose tissue, specialized in storing energy as fat. Adipocytes are derived from mesenchymal stem cells which give rise to adipocytes through adipogenesis. I ...

s and

endothelial The endothelium is a single layer of squamous endothelial cells that line the interior surface of blood vessels and lymphatic vessels. The endothelium forms an interface between circulating blood or lymph in the lumen and the rest of the vessel ...

cells.

Function

Activating CMKLR1 by an

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

mobilizes intracellular

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to ...

and causes the activation of several other signaling cascades like the

ERK1 Mitogen-activated protein kinase 3, also known as p44MAPK and ERK1, is an enzyme that in humans is encoded by the ''MAPK3'' gene. Function The protein encoded by this gene is a member of the mitogen-activated protein kinase (MAP kinase) famil ...

and

NF-κB Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a protein complex that controls transcription of DNA, cytokine production and cell survival. NF-κB is found in almost all animal cell types and is involved in cellular ...

. Initial studies of CMKLR1 suggested that it might have a role in the inflammatory pathways. Its cognate ligand, chemerin was found in joint aspirate from rheumatoid arthritis and absent in aspirate from degenerative arthritis. CMKLR1 expression by plasmacytoid dendritic cells and macrophages also helped foster this idea. In vitro

chemotaxis Chemotaxis (from '' chemo-'' + ''taxis'') is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemica ...

assays showed it to be utilized in attracting these cells. As an

adipokine The adipokines, or adipocytokines (Greek ', fat; ', cell; and ', movement) are cytokines (cell signaling proteins) secreted by adipose tissue. Some contribute to an obesity-related low-grade state of inflammation or to the development of metabolic ...

receptor it has a role in

adipogenesis Adipogenesis is the formation of adipocytes (fat cells) from stem cells. It involves 2 phases, determination, and terminal differentiation. Determination is mesenchymal stem cells committing to the adipocyte precursor cells, also known as preadipocy ...

and adipocyte maturation. It seems also to have a role in peripheral

insulin resistance Insulin resistance (IR) is a pathological condition in which cell (biology), cells fail to respond normally to the hormone insulin. Insulin is a hormone that facilitates the transport of glucose from blood into cells, thereby reducing blood gluco ...

. Also studies using the mouse

zymosan Zymosan is a glucan with repeating glucose units connected by β-1,3-glycosidic linkages. It binds to TLR 2 and Dectin-1 (CLEC7A C-type lectin domain family 7 member A or Dectin-1 is a protein that in humans is encoded by the ''CLEC7A'' gene. C ...

model and

chemerin peptides Chemerin peptides are short peptides (on the order of 9 amino acids) that are produced from the carboxyl terminus of the chemokine chemerin. They display the same activities as chemerin, although at higher efficacy and potency. A particular synth ...

showed that these peptides suppressed and helped resolve the

peritonitis Peritonitis is inflammation of the localized or generalized peritoneum, the lining of the inner wall of the abdomen and cover of the abdominal organs. Symptoms may include severe pain, swelling of the abdomen, fever, or weight loss. One part or ...

in mice. The same model showed that this particular molecule enhances macrophage

efferocytosis In cell biology, efferocytosis (from ''efferre'', Latin for 'to take to the grave', 'to bury') is the process by which apoptotic cells are removed by phagocytic cells. It can be regarded as the 'burying of dead cells'. During efferocytosis, the cel ...

(phagocyting apoptotic cells).

Receptor antagonist CCX832

CCX832 is an orally active molecule used as a

tool compound In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a ...

in experimental

pharmacology Pharmacology is a branch of medicine, biology and pharmaceutical sciences concerned with drug or medication action, where a drug may be defined as any artificial, natural, or endogenous (from within the body) molecule which exerts a biochemica ...

. It antagonises the effect of CMKLR1. It is listed on the

Guide to Pharmacology The IUPHAR/BPS Guide to PHARMACOLOGY is an open-access website, acting as a portal to information on the biological targets of licensed drugs and other small molecules. The Guide to PHARMACOLOGY (with GtoPdb being the standard abbreviation) is dev ...

database as the only example of a CMKLR1 antagonist. Its chemical structure is undisclosed. The substance was originally developed for use as a pharmaceutical drug against

inflammatory disease Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molecu ...

s by ChemoCentryx, a pharmaceutical firm based in California, in alliance with

GlaxoSmithKline GSK plc, formerly GlaxoSmithKline plc, is a British multinational pharmaceutical and biotechnology company with global headquarters in London, England. Established in 2000 by a merger of Glaxo Wellcome and SmithKline Beecham. GSK is the ten ...

(GSK). Development was terminated after a Phase I

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietar ...

in 2012.

Tissue distribution

Function

Receptor antagonist CCX832

References

External links

Further reading