Characterizing Proteins of Unknown Function: Orphan Cytochrome P450 Enzymes as a Paradigm

Table 1

Human P450 Orphans

P450 Site(s) of Expression Possible Substrates
2A71
2S1 Skin, liver (also trachea, lung, stomach, small intestine, spleen) (74, 76) (Retinoic acid, carcinogens?) (72, 76–78, 81)
2U1 Thymus, brain (56, 57) Fatty acids (ω, ω-1) (56, 57)
2W1 Tumors (72, 73) Carcinogens (72)
3A431
4A221
4F11 Liver (86) Fatty acids (ω-1, -2, -3...), β-hydroxy fatty acids (33, 55)
4F221
4V2 Eye (87) Fatty acids (ω) (58)
4X1 Brain, liver (59) Anandamide (59)
4Z1 Breast cancer (88) Fatty acids (ω-2, -3, -4, -5) (60)
20A1 Brain, liver (84) (Unknown) (84)
27C1 Liver, kidney, spleen, others (85) (Unknown) (85)
  • 1 The literature is not clear whether these are expressed.

This Article

  1. MI June 2010 vol. 10 no. 3 153-163