Dihydrofolate reductase (DHFR) and dihydroorotate dehydrogenase (DODH) are enzymes involved in cellular metabolism. The left image shows the localization of DODH (green) and the right image shows the localization of DHFR (green). The red staining shows microtubules and the purple in the DHFR-labeled cells shows the nucleus. The left image is MCF7 cells (a breast cancer cell line) stained for DODH, which is found in the nucleus and in mitochondria (Image ID HPA011942). The right image shows DHFR staining of a prostate cancer cell line (PC-3). DHFR is localized in mitochondria (Image ID: HPA051465) Image Credit: Human Protein Atlas
https://www.proteinatlas.org/ENSG00000102967-DHODH/cell#img
https://www.proteinatlas.org/ENSG00000228716-DHFR/cell#img
See related commentary
N. R. Gough, Immunomodulators for Arthritis: Small-Molecule Disease-Modifying Agents. BioSerendipity (29 January 2018).