Conserved Site

Erythropoietin/thrombopoeitin, conserved site (IPR019767)

Short name: EPO/TPO_CS


Erythropoietin, a plasma glycoprotein, is the primary physiological mediator of erythropoiesis [PMID: 3773894]. It is involved in the regulation of the level of peripheral erythrocytes by stimulating the differentiation of erythroid progenitor cells, found in the spleen and bone marrow, into mature erythrocytes [PMID: 3346214]. It is primarily produced in adult kidneys and foetal liver, acting by attachment to specific binding sites on erythroid progenitor cells, stimulating their differentiation [PMID: 2877922]. Severe kidney dysfunction causes reduction in the plasma levels of erythropoietin, resulting in chronic anaemia - injection of purified erythropoietin into the blood stream can help to relieve this type of anaemia. Levels of erythropoietin in plasma fluctuate with varying oxygen tension of the blood, but androgens and prostaglandins also modulate the levels to some extent [PMID: 2877922]. Erythropoietin glycoprotein sequences are well conserved, a consequence of which is that the hormones are cross-reactive among mammals, i.e. that from one species, say human, can stimulate erythropoiesis in other species, say mouse or rat [PMID: 1420369].

Thrombopoeitin (TPO), a glycoprotein, is the mammalian0 hormone which functions as a megakaryocytic lineage specific growth and differentiation factor affecting the proliferation and maturation from their committed progenitor cells acting at a late stage of megakaryocyte development. It acts as a circulating regulator of platelet numbers.

EPO and TPO are evolutionary related. As a signature pattern, this entry represents a conserved region located at the N-terminal extremity of mature EPO and TPO and that includes two cysteines which have been shown, in human EPO, to be implicated in disulphide bonds.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005179 hormone activity

Cellular Component

GO:0005576 extracellular region

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns