Part:BBa_K4160001

EpoR (erythropoietin receptor)

The erythropoietin receptor (EpoR) is a type I cytokine receptor. This receptor induces downstream signaling after binding of its ligand erythropoietin (Epo).¹ The EpoR forms the foundation of the Generalized Extraceullar Molecule Sensor (GEMS) receptor that was developed by Schneller et al., 2018.² This part encodes for an EpoR construct that has been designed to develop the GEMS receptor. This construct is a truncated form of the EpoR that has been mutated to render it inert to Epo.²

Sequence and Features

Assembly Compatibility:

• 10
  INCOMPATIBLE WITH RFC[10]

  Illegal PstI site found at 289
  
• 12
  INCOMPATIBLE WITH RFC[12]

  Illegal NheI site found at 658
  Illegal PstI site found at 289
  
• 21
  INCOMPATIBLE WITH RFC[21]

  Illegal XhoI site found at 172
  
• 23
  INCOMPATIBLE WITH RFC[23]

  Illegal PstI site found at 289
  
• 25
  INCOMPATIBLE WITH RFC[25]

  Illegal PstI site found at 289
  
• 1000
  COMPATIBLE WITH RFC[1000]

Usage and Biology

The erythropoietin receptor (EpoR) is a type I cytokine receptor,¹ that originates from Homo sapiens (Human).³ The EpoR is predominantly expressed on the surface of immature erythroid cells.¹ Together with its ligand Epo, it is the primary regulator of mammalian erythropoiesis (the production of red blood cells).⁴ Binding of Epo to the EpoR induces proliferation, survival, and differentiation of erythroid progenitors into red blood cells.^1,4
When EpoR is in its inactive form, the EpoR dimers are locked by transmembrane helix interactions. This conformation prevents downstream signaling.² Binding of the hormone Epo induces reorientation and dimerization of two EpoR monomers, which forms an active dimeric receptor structure (Figure 1). Consequently, signal transduction via Janus Kinase 2 (JAK2) is initiated by the intracellular domains of the EpoR.^1,4

Figure 1 | Activation of the erythropoietin receptor. In the presence of erythropoietin, the EpoR activates through a conformational change between the two receptor subunits.

Modularity

Due to the simplicity of molecular structures and activation modes, type I cytokine receptors have been engineered intensively.⁵ Cytokine receptors have a modular structure that permits the combination of different intracellular and extracellular domains.² Therefore, the extracellular affinity domains of cytokine receptors can be modified easily, without adjusting downstream signaling properties.⁵ Hence, synthetic cytokine receptors are emerging as a platform to develop improved and modulated immunotherapeutic strategies.⁶

GEMS receptor

The TU-Eindhoven team 2022 used this part to form the robust, modular GEMS receptor (BBa_K4160008). Different synthetic receptors were developed by fusing several affinity domains to the N-terminus of the EpoR. In addition, the intracellular transduction domain IL-6RB (BBa_K4160002) was fused C-terminal transmembrane domain of the EpoR. Due to its modularity, the EpoR provides a valuable platform for studies in synthetic biology and for the development of cell-based therapies.² Hence, this part, which other iGEM teams can use effortlessly, has much potential for therapeutics.

Characterization

Characterization of the EpoR incorporated in the GEMS receptor can be found on the BBa_K4160008 page.

References

1. Watowich SS. The Erythropoietin Receptor. J Investig Med. 2011;59(7):1067-1072. doi:10.2310/JIM.0B013E31820FB28C
2. Scheller L, Strittmatter T, Fuchs D, Bojar D, Fussenegger M. Generalized extracellular molecule sensor platform for programming cellular behavior. Nat Chem Biol. Published online 2018. doi:10.1038/s41589-018-0046-z
3. EPOR - Erythropoietin receptor - Homo sapiens (Human) | UniProtKB | UniProt. Accessed October 10, 2022. https://www.uniprot.org/uniprotkb/P19235/entry
4. Seubert N, Royer Y, Staerk J, et al. Active and Inactive Orientations of the Transmembrane and Cytosolic Domains of the Erythropoietin Receptor Dimer. Mol Cell. 2003;12(5):1239-1250. doi:10.1016/S1097-2765(03)00389-7
5. Kawahara M, Nagamune T. Engineering of mammalian cell membrane proteins. Curr Opin Chem Eng. 2012;1(4):411-417. doi:10.1016/J.COCHE.2012.05.002
6. Scheller J, Engelowski E, Moll JM, Floss DM. Immunoreceptor Engineering and Synthetic Cytokine Signaling for Therapeutics. Trends Immunol. 2019;40:258-272. doi:10.1016/j.it.2019.01.001