MRC1 (mannose receptor, C type 1)

2010-01-01   Silvia Rasi , Alessio Bruscaggin , Gianluca Gaidano 

Division of Hematology, Department of Clinical, Experimental Medicine & Center of Biotechnologies for Applied Medical Research, Amedeo Avogadro University of Eastern Piedmont, Via Solaroli 17, 28100 Novara, Italy


Atlas Image
A. Chromosomal location of MRC1 gene.
B. Mapping of MRC1 gene and local order on genomic context of the chromosome 10.


Atlas Image
Exon-intron structure of MRC1 gene. The blue boxes correspond to protein coding sequences, while the white boxes correspond to non coding regions.


MRC1 is a functional gene of 101.74 kb comprising 30 exons and 29 introns. The 5 part of exon 1 and the 3 part of exon 30 are non coding.


Length of the transcript is 5171 bp.
Coding sequence: CDS 104-4474.
mRNA is mainly expressed in thyroid, spleen and blood.


Atlas Image
Representation of the MRC1 protein with localization of recognized domains. The ricin b-type lectin domain (RICIN) is shown in green, the fibronectin type-II domain (FN2) in yellow, the C-type lectin-like domains (CTLDs) in blue, while the transmembrane domain (TM) in red (UniProtKB/Swiss-Prot entry P22897).


Protein length of the unprocessed precursor: 1456 amino acids.
Molecular weight of the unprocessed precursor: 166 KDa.
The protein encoded by the MRC1 gene is classified as a type I transmembrane receptor since the protein COOH terminus is located on the cytoplasmic side of the membrane.
MRC1 is a membrane receptor containing:
- a ricin b-type lectin domain (RICIN), that is a cystein-rich (CysR) domain located at the extreme N-terminus and that can bind specific sulphated glycoproteins,
- a fibronectin type-II domain (FN2), that is the most conserved of the extracellular domains of the MR family and can bind several forms of collagen,
- 8 C-type lectin-like domains (CTLDs), that are Ca(2+)-dependent structural motifs. The fourth of these domains, CTLD4, is the only functional domain. In cooperation with CTLD5, CTLD4 is central to ligand binding by the receptor,
- a single transmembrane domain (TM),
- a short cytosolic domain that contains motifs capable of recognizing components of the endocytic pathway.
The first 3 exons of MRC1 gene encode the signal sequence, the RICIN domain and the FN2 domain, while exon 30 encodes the TM anchor and the cytoplasmic tail. The other 26 exons encode the 8 CTLD domains and intervening spacer elements.
Probably the MRC1 receptor acts with an alternation between bent and extended conformations, that might serve as a "conformational switch" to regulate ligand binding and receptor activity.
MRC1 interacts with CHEK2 (CHK2 checkpoint homolog - S. pombe) protein.


MRC1 is commonly expressed on macrophages and endothelial cells.


Plasma membrane.


- MRC1 mediates the endocytosis of glyproteins by macrophages binding both sulfated and non-sulfated polysaccharide chains.
- MRC1 acts as a phagocytic receptor binding a range of pathogens, such as bacteria, viruses and fungi, through high-mannose structures that are in their surface.
- MRC1 is required for rapid clearance of a subset of mannose-bearing serum glycoproteins that are normally elevated during inflammation.
- MRC1 binds and internalises collagen and gelatin in a carbohydrate-independent mechanism.
- MRC1 can function as an antigen-acquisition system in a subset of dendritic cells.
- MRC1 is implicated in the regulation of macrophage migration during different stages of pathogenesis.
- MRC1 has an important role in binding and transmission of HIV-1 by macrophages.


Ortholog to murine Mrc1, rat Mrc1, cow LOC787578, chimpanzee MLR1L1, canine LOC487114.
Paralog to MRC1L1, CD302, PLA2R1, MRC2.



No mutations have been reported for MRC1 gene.

Implicated in

ALL is a form of leukemia characterized by excess of lymphoblastic cells that is most common in childhood. The rate of cure in children is of nearly 80%, while only 30/40% of adults with ALL are cured.
It is a heterogeneous disease consisting of a number of genetically distinct leukemia subtypes that differ in the response to chemotherapy. These include B-lineage leukemias that contain t(9;22)[BCR-ABL], t(1;19)[E2A-PBX1], t(12;21)[TEL-AML1], rearrangements in the MLL gene on chromosome 11q23, or a hyperdiploid karyotype, and T-lineage leukemias (T-ALL).
ALL is a heterogeneous disease and patients are assigned to specific risk groups. In fact, ALL prognosis differs among individuals and depends on several factors: sex, age and white blood cell count at diagnosis, leukemia spread to the central nervous system, morphological, immunological, and genetic subtypes, patients response to initial treatment.
Various genetic alterations are correlated with prognosis in ALL. In particular ALLs with the presence of t(12;21)[TEL-AML1] and hyperdiploid karyotype have favorable prognosis, while ALLs with t(9;22)[BCR-ABL], t(1;19)[E2A-PBX1] or rearrangements in MLL (11q23) have a poor prognosis.
In cases having ALL with MLL rearrangements, expression of MRC1 is lower than in normal cells, suggesting a putative involvement of MRC1 in MLL-mediated growth of leukemic cells.
Entity name
Acute monocytic leukemia (M5-AML)
In acute monocytic leukemia, a trimannose conjugate (TMC), with a high affinity for mannose-specific lectins, binds to MRC1 and this concatenation may play an important role in the activation of monocytic leukemia cells. TMC may be a good candidate to target MRC1 in leukemia cells.
Acute monocytic leukemia is a type of acute myeloid leukemias (AML), characterized by a dominance of monocytes in the bone marrow.
Entity name
MRC1 on lymphatic endothelial cells is involved in leukocyte trafficking and contributes to the metastatic behavior of cancer cells. Moreover, expression of the MRC1 gene is up-regulated in vascular endothelial cells during early development indicating that this gene is a potential regulator of vasculature formation.
Blocking of MRC1 may provide a new approach to controlling inflammation and cancer metastasis by targeting the lymphatic vasculature.
Entity name
Kaposis sarcoma (KS)
KS cells express MRC1, since MRC1 is detected in more than 95% of KS cells in all of the major clinical forms of the disease. It is likely that KS lesions derive from tissue accumulation and local proliferation of a subset of macrophages with endotelial features.
KS is a multicentric proliferative disease, involving cutaneous and visceral tissues. The etiology is unknown and the pathogenesis is unclear. KS lesions derive from local proliferation of spindleshaped cells (KS cells), that represent the histological hallmark of this disease.


Pubmed IDLast YearTitleAuthors
122232802002The mannose receptor family.East L et al
80019821994Assignment of the human macrophage mannose receptor gene (MRC1) to 10p13 by in situ hybridization and PCR-based somatic cell hybrid mapping.Eichbaum Q et al
117219682001Novel synthesized trimannose conjugate induces endocytosis and expression of immunostimulatory molecules in monocytic leukemia cells.Kanbe E et al
12941181992Organization of the gene encoding the human macrophage mannose receptor (MRC1).Kim SJ et al
118847562002Mannose receptor-mediated regulation of serum glycoprotein homeostasis.Lee SJ et al
181931592008Extended and bent conformations of the mannose receptor family.Llorca O et al
166192932006Carbohydrate-independent recognition of collagens by the macrophage mannose receptor.Martinez-Pomares L et al
184346102008Macrophage mannose receptor on lymphatics controls cell trafficking.Marttila-Ichihara F et al
174042792007Mannose receptor expression and function define a new population of murine dendritic cells.McKenzie EJ et al
126459472003Involvement of macrophage mannose receptor in the binding and transmission of HIV by macrophages.Nguyen DG et al
97183811998Acute lymphoblastic leukemia.Pui CH et al
175963372007Mannose receptor regulation of macrophage cell migration.Sturge J et al
23736851990Primary structure of the mannose receptor contains multiple motifs resembling carbohydrate-recognition domains.Taylor ME et al
90608311997Kaposi's sarcoma cells express the macrophage-associated antigen mannose receptor and develop in peripheral blood cultures of Kaposi's sarcoma patients.Uccini S et al
195044562009Identification of vasculature-specific genes by microarray analysis of Etsrp/Etv2 overexpressing zebrafish embryos.Wong KS et al
120868722002Classification, subtype discovery, and prediction of outcome in pediatric acute lymphoblastic leukemia by gene expression profiling.Yeoh EJ et al

Other Information

Locus ID:

NCBI: 4360
MIM: 153618
HGNC: 7228
Ensembl: ENSG00000260314


dbSNP: 4360
ClinVar: 4360
TCGA: ENSG00000260314


Gene IDTranscript IDUniprot

Expression (GTEx)



PathwaySourceExternal ID
Immune SystemREACTOMER-HSA-168256
Adaptive Immune SystemREACTOMER-HSA-1280218
Class I MHC mediated antigen processing & presentationREACTOMER-HSA-983169
Antigen processing-Cross presentationREACTOMER-HSA-1236975
Cross-presentation of soluble exogenous antigens (endosomes)REACTOMER-HSA-1236978

Protein levels (Protein atlas)

Not detected


Pubmed IDYearTitleCitations
197728902009Mesenchymal stem cell-educated macrophages: a novel type of alternatively activated macrophages.236
162038682005The human macrophage mannose receptor directs Mycobacterium tuberculosis lipoarabinomannan-mediated phagosome biogenesis.164
145689282003Cross-linking of the mannose receptor on monocyte-derived dendritic cells activates an anti-inflammatory immunosuppressive program.108
205549622010Mycobacterium tuberculosis activates human macrophage peroxisome proliferator-activated receptor gamma linking mannose receptor recognition to regulation of immune responses.92
163854512006A scan of chromosome 10 identifies a novel locus showing strong association with late-onset Alzheimer disease.69
206106552010The mannose receptor mediates the uptake of diverse native allergens by dendritic cells and determines allergen-induced T cell polarization through modulation of IDO activity.57
213313652010Engagement of the mannose receptor by tumoral mucins activates an immune suppressive phenotype in human tumor-associated macrophages.38
151556162004Pneumocystis activates human alveolar macrophage NF-kappaB signaling through mannose receptors.35
244980982014Overexpression of CD163, CD204 and CD206 on alveolar macrophages in the lungs of patients with severe chronic obstructive pulmonary disease.34
170209282007Pneumocystis-mediated IL-8 release by macrophages requires coexpression of mannose receptors and TLR2.33


Silvia Rasi ; Alessio Bruscaggin ; Gianluca Gaidano

MRC1 (mannose receptor, C type 1)

Atlas Genet Cytogenet Oncol Haematol. 2010-01-01

Online version: