Tyrosine kinase with immunoglobulin-like and EGF-like domains 1 also known as TIE1 is an angiopoietin receptor which in humans is encoded by the TIE1 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...

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Function

TIE1 is a cell surface protein expressed exclusively in 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...

 cells, however it has also been shown to be expressed in immature hematopoietic cells. TIE1 upregulates the cell adhesion molecule

Cell adhesion molecule

Cell Adhesion Molecules are proteins located on the cell surface involved with the binding with other cells or with the extracellular matrix in the process called cell adhesion....

s (CAMs) 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...

, E-selectin

E-selectin

E-selectin, also known as CD62 antigen-like family member E , endothelial-leukocyte adhesion molecule 1 , or leukocyte-endothelial cell adhesion molecule 2 , is a cell adhesion molecule expressed only on endothelial cells activated by cytokines. Like other selectins, it plays an important part in...

, and 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...

  through a p38

P38 mitogen-activated protein kinases

P38 mitogen-activated protein kinases are a class of mitogen-activated protein kinases that are responsive to stress stimuli, such as cytokines, ultraviolet irradiation, heat shock, and osmotic shock, and are involved in cell differentiation and apoptosis....

-dependent mechanism. Attachment of monocyte

Monocyte

Monocytes are a type of white blood cell and are part of the innate immune system of vertebrates including all mammals , birds, reptiles, and fish. Monocytes play multiple roles in immune function...

 derived immune cells to endothelial cells is also enhanced by TIE1 expression. TIE1 has a proinflammatory effect and may play a role in the endothelial inflammatory diseases such as atherosclerosis

Atherosclerosis

Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol...

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