|MARCO||MRCO (macrophage receptor with collagenous structure)|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 2 glycoprotein
|80 / 80|
210 / 210
|MARCO is expressed on macrophages in the marginal zone of the spleen and in the medullary cord of lymph nodes but not in the liver or lung.|
|MOLECULAR FAMILY NAME: Belong to the scavenger receptor cysteine-rich family.|
MARCO is a single-pass homotrimeric type-2 520 aa glycoprotein. It contains an extracellular domain which contains 1 270 aa collagen-like domain with glycine repeats, a 75 aa putative spacer domain with 2 potential N-linkled glycosylation sites and a cysteine-rich domain (SRCR) at the C terminus, a 25 aa transmembrane domain and a 49 aa N-terminal cytoplasmic sequence. It is a member of the Group A scavenger receptor cysteine- rich (SRCR) superfamily. It is expressed as a disulfide-linked trimer at the cell surface. The mouse MARCO is a plasma membrane protein but the human MARCO polypeptide lacks the intracellular cysteine present in the mouse as well as two extracellular cysteines that form interchain disulfide bonds in the murine protein. The predicted structure of MARCO is similar to scavenger receptor but differs in that MARCO has a longer collagenous domain where scavenger receptor has a coiled-coil region followed by a short collagen-like region. The scavenger receptor domains of MARCO and scavenger receptor type 1 show a 49% aa sequence identity and each contain 6 cysteines.
POST-TRANSCRIPTIONAL MODIFICATION: No information.
MARCO has 2 potential glycosylation sites.
|LIGANDS AND MOLECULES ASSOCIATED WITH MARCO|
COS cells expressing MARCO bind an acetylated low density lipoprotein and bacteria, specifically, E. coli and S. aureus.
MARCO is a member of the scavenger receptor family and is part of the innate antimicrobial immune system. It binds Gram-positive and Gram-negative bacteria via an extracellular, C-terminal scavenger receptor cystrine rich domain. MARCO may form a trimeric molecule by the association of the collagenous domains of three identical polypeptide chains.
PROTEINS ANDS DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF MARCO: No information.
SUBSTRATES: No information.
ENZYMES WHICH MODIFY MARCO: No information.
Database accession numbers
Revised June 25, 2008