| GO:0016020 | membrane | 46 | 1681 |
| GO:0005515 | protein binding | 198 | 6024 |
| GO:0042167 | heme catabolic process | 2 | 6 |
| GO:0006879 | cellular iron ion homeostasis | 3 | 51 |
| GO:0044281 | small molecule metabolic process | 20 | 1211 |
| GO:0001666 | response to hypoxia | 7 | 149 |
| GO:0046872 | metal ion binding | 29 | 1307 |
| GO:0055085 | transmembrane transport | 8 | 435 |
| GO:0004392 | heme oxygenase (decyclizing) activity | 2 | 2 |
| GO:0006778 | porphyrin-containing compound metabolic process | 2 | 18 |
| GO:0006788 | heme oxidation | 2 | 2 |
| GO:0005789 | endoplasmic reticulum membrane | 9 | 570 |
| GO:0005886 | plasma membrane | 49 | 2582 |