Explore HT
Gene
EIF2AK1
Uniprot
Q9BQI3
Protein
Eukaryotic translation initiation factor 2-alpha kinase 1
See alternative names Heme-controlled repressor,
Heme-regulated eukaryotic initiation factor eIF-2-alpha kinase,
Heme-regulated inhibitor,
Hemin-sensitive initiation factor 2-alpha kinase
Uniprot Function Description
Metabolic-stress sensing protein kinase that phosphorylates the alpha subunit of eukaryotic translation initiation factor 2 (EIF2S1/eIF-2-alpha) in response to various stress conditions (PubMed:32132706, PubMed:32132707). Key activator of the integrated stress response (ISR) required for adaptation to various stress, such as heme deficiency, oxidative stress, osmotic shock, mitochondrial dysfunction and heat shock (PubMed:32132706, PubMed:32132707). EIF2S1/eIF-2-alpha phosphorylation in response to stress converts EIF2S1/eIF-2-alpha in a global protein synthesis inhibitor, leading to a global attenuation of cap-dependent translation, while concomitantly initiating the preferential translation of ISR-specific mRNAs, such as the transcriptional activator ATF4, and hence allowing ATF4-mediated reprogramming (PubMed:32132706, PubMed:32132707). Acts as a key sensor of heme-deficiency: in normal conditions, binds hemin via a cysteine thiolate and histidine nitrogenous coordination, leading to inhibit the protein kinase activity (By similarity). This binding occurs with moderate affinity, allowing it to sense the heme concentration within the cell: heme depletion relieves inhibition and stimulates kinase activity, activating the ISR (By similarity). Thanks to this unique heme-sensing capacity, plays a crucial role to shut off protein synthesis during acute heme-deficient conditions (By similarity). In red blood cells (RBCs), controls hemoglobin synthesis ensuring a coordinated regulation of the synthesis of its heme and globin moieties (By similarity). It thereby plays an essential protective role for RBC survival in anemias of iron deficiency (By similarity). Also activates the ISR in response to mitochondrial dysfunction: HRI/EIF2AK1 protein kinase activity is activated upon binding to the processed form of DELE1 (S-DELE1), thereby promoting the ATF4-mediated reprogramming (PubMed:32132706, PubMed:32132707).
Sample type
Recommended sample types are human plasma and serum. For other sample types e.g cerebrospinal fluid, (CSF), tissue or cell lysate, please contact support@olink.com for more information. Please note that protein expression levels are expected to vary in different sample types and certain assays may be affected by interfering substances such as hemolysate.
Precision
Precision (repeatability) is calculated from linearized NPX values over LOD.
Analytical measuring range
The technical data reported below refers to the measured value in the in vitro validation assays run using known concentrations of recombinant antigen.
Dilution factor
For optimal assay readout, Olink assays are run using different dilutions of the original samples e.g. undiluted, 1:10, or higher. The dilution factor for this assay is noted below and should be taken into account when estimating the appropriate addressable biological concentration of the protein based on the in vitro validation data.
Biomarker Validation Data
Additional validation data, as well as a more detailed description of how the Olink panels are quality controlled can be found in our Data Validation documents – go to Document download center