Erythropoietin production is directly and indirectly (via regulatory genes) increased by HIF-1 (Hypoxia inducible factor 1) which is a transcription activator that is oxygen sensitive. | Erythropoietin production is directly and indirectly (via regulatory genes) increased by HIF-1 (Hypoxia inducible factor 1) which is a transcription activator that is oxygen sensitive. |