Lymphotoxin beta receptor (LTBR), also known as tumor necrosis factor receptor superfamily member 3 (TNFRSF3), is a
cell surface receptor
Cell surface receptors (membrane receptors, transmembrane receptors) are receptors that are embedded in the plasma membrane of cells. They act in cell signaling by receiving (binding to) extracellular molecules. They are specialized integra ...
for
lymphotoxin
Lymphotoxin is a member of the tumor necrosis factor (TNF) superfamily of cytokines, whose members are responsible for regulating the growth and function of lymphocytes and are expressed by a wide variety of cells in the body.
Lymphotoxin plays ...
involved in
apoptosis
Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...
and
cytokine
Cytokines () are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling.
Cytokines are produced by a broad range of cells, including immune cells like macrophages, B cell, B lymphocytes, T cell, T lymphocytes ...
release.
It is a member of the
tumor necrosis factor receptor superfamily.
Function
The protein encoded by this gene is a member of the
tumor necrosis factor
Tumor necrosis factor (TNF), formerly known as TNF-α, is a chemical messenger produced by the immune system that induces inflammation. TNF is produced primarily by activated macrophages, and induces inflammation by binding to its receptors o ...
(TNF) family of receptors. It is expressed on the surface of most cell types, including cells of
epithelial
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of man ...
and
myeloid
Myeloid tissue, in the bone marrow sense of the word '' myeloid'' ('' myelo-'' + '' -oid''), is tissue of bone marrow, of bone marrow cell lineage, or resembling bone marrow, and myelogenous tissue (''myelo-'' + '' -genous'') is any tissue ...
lineages, but not on
T and
B lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include T cells (for cell-mediated and cytotoxic adaptive immunity), B cells (for humoral, antibody-driven adaptive immunity), an ...
s. The protein specifically binds the
lymphotoxin
Lymphotoxin is a member of the tumor necrosis factor (TNF) superfamily of cytokines, whose members are responsible for regulating the growth and function of lymphocytes and are expressed by a wide variety of cells in the body.
Lymphotoxin plays ...
membrane form (a complex of lymphotoxin-alpha and lymphotoxin-beta). The encoded protein and its ligand play a role in the development and organization of
lymphoid tissue
The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphoid organs, lympha ...
and transformed cells. Activation of the encoded protein can trigger apoptosis.
Not only does the LTBR help trigger apoptosis, it can lead to the release of the
cytokine
Cytokines () are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling.
Cytokines are produced by a broad range of cells, including immune cells like macrophages, B cell, B lymphocytes, T cell, T lymphocytes ...
interleukin 8
Interleukin 8 (IL-8 or chemokine (C-X-C motif) ligand 8, CXCL8) is a chemokine produced by macrophages and other cell types such as epithelial cells, airway smooth muscle cells and endothelial cells. Endothelial cells store IL-8 in their stor ...
. Overexpression of LTBR in
HEK293 cells increases IL-8 promoter activity and leads to IL-8 release. LTBR is also essential for development and organization of the secondary lymphoid organs and chemokine release.
Structure
The Ramachandran plots show that 64.6% of all residues were in a favored region.
This structure was found using X-ray diffraction. The resolution is 3.50 angstroms.
The alpha and beta angles are 90 degrees while the gamma angle is 120 degrees.
Interactions
Lymphotoxin beta receptor has been shown to
interact with
Diablo homolog and
TRAF3.
References
Further reading
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External links
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{{TNF receptor superfamily modulators
TNF receptor family