Addressin also known as mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1) is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the MADCAM1 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

Addressin is an extracellular

Extracellular

In cell biology, molecular biology and related fields, the word extracellular means "outside the cell". This space is usually taken to be outside the plasma membranes, and occupied by fluid...

 protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 of the endothelium

Endothelium

The endothelium is the thin layer of cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. These cells are called endothelial cells. Endothelial cells line the entire circulatory system, from the heart...

 of venule

Venule

A venule is a very small blood vessel in the microcirculation that allows deoxygenated blood to return from the capillary beds to the larger blood vessels called veins. Venules range from 8 to 100μm in diameter and are formed when capillaries unite .Venules are blood vessels that drain blood...

s. Addressins are the ligand

Ligand

In coordination chemistry, a ligand is an ion or molecule that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from...

s to the homing receptors of lymphocyte

Lymphocyte

A lymphocyte is a type of white blood cell in the vertebrate immune system.Under the microscope, lymphocytes can be divided into large lymphocytes and small lymphocytes. Large granular lymphocytes include natural killer cells...

s. The task of these ligands and their receptors is to determine which tissue the lymphocyte will enter next. They carry carbohydrates in order to be recognized by L-selectin

L-selectin

L-selectin, also known as CD62L, is a cell adhesion molecule found on leukocytes. It belongs to the selectin family of proteins, which recognize sialylated carbohydrate groups...

.

Function

The protein encoded by this gene is an endothelial

Endothelium

The endothelium is the thin layer of cells that lines the interior surface of blood vessels, forming an interface between circulating blood in the lumen and the rest of the vessel wall. These cells are called endothelial cells. Endothelial cells line the entire circulatory system, from the heart...

 cell adhesion

Cell adhesion

Cellular adhesion is the binding of a cell to a surface, extracellular matrix or another cell using cell adhesion molecules such as selectins, integrins, and cadherins. Correct cellular adhesion is essential in maintaining multicellular structure...

 molecule that interacts preferentially with the leukocyte beta7 integrin LPAM-1 (alpha4

ITGA7

Integrin alpha-7 is a protein that in humans is encoded by the ITGA7 gene.-Interactions:ITGA7 has been shown to interact with FHL2 and FHL3.-External links:* Info with links in the...

 / beta7

ITGB7

Integrin beta-7 is a protein that in humans is encoded by the ITGB7 gene.-External links:* Info with links in the...

), L-selectin

L-selectin

L-selectin, also known as CD62L, is a cell adhesion molecule found on leukocytes. It belongs to the selectin family of proteins, which recognize sialylated carbohydrate groups...

, and VLA-4

VLA-4

Integrin alpha4beta1 is an integrin dimer. It is composed of CD49d and CD29 .VCAM-1 binds to the integrin VLA-4 which are normally expressed on leukocyte plasma membranes, but they do not adhere to their appropriate ligands until the leukocytes are activated by chemotactic agents or other...

 (alpha4 / beta1

CD29

Integrin beta-1 is a protein that in humans is encoded by the ITGB1 gene. CD29 is an integrin unit associated with very late antigen receptors. It is known to conjoin with alpha-3 subunit to create α3β1 complex that reacts to such molecules as netrin-1 and reelin.Integrins are heterodimeric...

) on myeloid cells to direct leukocytes into mucosal and inflamed tissues. It is a member of the immunoglobulin superfamily

Immunoglobulin superfamily

The immunoglobulin superfamily is a large group of cell surface and soluble proteins that are involved in the recognition, binding, or adhesion processes of cells. Molecules are categorized as members of this superfamily based on shared structural features with immunoglobulins ; they all possess a...

 and is similar to ICAM-1

ICAM-1

ICAM-1 also known as CD54 is a protein that in humans is encoded by the ICAM1 gene. This gene encodes a cell surface glycoprotein which is typically expressed on endothelial cells and cells of the immune system...

 and VCAM-1

VCAM-1

Vascular cell adhesion protein 1 also known as vascular cell adhesion molecule 1 or cluster of differentiation 106 is a protein that in humans is encoded by the VCAM1 gene...

.