Interleukin 3
Encyclopedia
Interleukin 3, also known as IL-3, is a protein
that in humans is encoded by the IL3 gene
.
, a type of biological signal (cytokine
) that can improve the body's natural response to disease as part of the immune system. It acts by binding to the interleukin-3 receptor
.
IL-3 stimulates the differentiation of multipotent hematopoietic stem cells into myeloid progenitor cells (as opposed to lymphoid progenitor cells where differentiation is stimulated by IL-7
) as well as stimulates proliferation of all cells in the myeloid lineage (erythrocytes, megakaryocyte
s, granulocyte
s, monocyte
s, and dendritic cell
s). It is secreted by basophils and activated T cells to support growth and differentiation of T cells from the bone marrow in an immune response. The human IL-3 gene encodes a protein 152 amino acids long, and the naturally occurring IL-3 is glycosylated. The human IL-3 gene is located on chromosome 5
, only 9 kilobases from the GM-CSF gene, and its function is quite similar to GM-CSF.
with IL3RA
.
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 IL3 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...
.
Function
Interleukin-3 (IL-3) is an interleukinInterleukin
Interleukins are a group of cytokines that were first seen to be expressed by white blood cells . The term interleukin derives from "as a means of communication", and "deriving from the fact that many of these proteins are produced by leukocytes and act on leukocytes"...
, a type of biological signal (cytokine
Cytokine
Cytokines are small cell-signaling protein molecules that are secreted by the glial cells of the nervous system and by numerous cells of the immune system and are a category of signaling molecules used extensively in intercellular communication...
) that can improve the body's natural response to disease as part of the immune system. It acts by binding to the interleukin-3 receptor
Interleukin-3 receptor
The interleukin-3 receptor is a molecule found on cells which helps transmit the signal of interleukin-3, a soluble cytokine important in the immune system....
.
IL-3 stimulates the differentiation of multipotent hematopoietic stem cells into myeloid progenitor cells (as opposed to lymphoid progenitor cells where differentiation is stimulated by IL-7
Interleukin 7
IL-7 a hematopoietic growth factor secreted by stromal cells in the red marrow and thymus. It is also produced by keratinocytes, dendritic cells, hepatocytes, neurons, and epithelial cells but is not produced by lymphocytes.- Genetics :...
) as well as stimulates proliferation of all cells in the myeloid lineage (erythrocytes, megakaryocyte
Megakaryocyte
The megakaryocyte is a bone marrow cell responsible for the production of blood thrombocytes , which are necessary for normal blood clotting...
s, granulocyte
Granulocyte
Granulocytes are a category of white blood cells characterized by the presence of granules in their cytoplasm. They are also called polymorphonuclear leukocytes because of the varying shapes of the nucleus, which is usually lobed into three segments...
s, 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...
s, and dendritic cell
Dendritic cell
Dendritic cells are immune cells forming part of the mammalian immune system. Their main function is to process antigen material and present it on the surface to other cells of the immune system. That is, dendritic cells function as antigen-presenting cells...
s). It is secreted by basophils and activated T cells to support growth and differentiation of T cells from the bone marrow in an immune response. The human IL-3 gene encodes a protein 152 amino acids long, and the naturally occurring IL-3 is glycosylated. The human IL-3 gene is located on chromosome 5
Chromosome 5 (human)
Chromosome 5 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 5 spans about 181 million base pairs and represents almost 6% of the total DNA in cells. Chromosome 5 is one of the largest human chromosomes, yet has one of the lowest gene...
, only 9 kilobases from the GM-CSF gene, and its function is quite similar to GM-CSF.
Discovery
Interleukin-3 originally was discovered by JN Ihle in mice. He found a T cell derived factor that induced the synthesis of 20alpha-hydroxysteroid dehydrogenase in hematopoietic cells and termed it interleukin-3.Interactions
Interleukin 3 has been shown to interactProtein-protein interaction
Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...
with IL3RA
IL3RA
Interleukin 3 receptor, alpha , also known as CD123 , is a human gene.-Interactions:IL3RA has been shown to interact with Interleukin 3.-External links:...
.