The following enzymes belong to a conserved family of sterol reductases which
act by reducing double bonds [1,2]:
Fungal delta(14)-sterol reductase (EC 184.108.40.206) (C-14 sterol reductase)
(gene ERG24 in budding yeast), an enzyme of ergosterol biosynthesis.
Mammalian (TM7SF2) and plant delta(14)-sterol reductases.
Fungal delta(24(24(1)))-sterol reductase (EC 220.127.116.11) (C-24(28) sterol
reductase) (gene ERG4 in budding yeast), an enzyme of ergosterol
Mammalian 7-dehydrocholesterol reductase (EC 18.104.22.168) which produces
cholesterol by reduction of C7-C8 double bond of 7-dehydrocholesterol (7-
Lamin B receptor, which is thought to anchor the lamina to the inner
All these proteins are highly hydrophobic and seem to contain seven or eight
transmembrane regions. As signature patterns, we selected two conserved
regions. The first one is apparently located in a loop between the fourth and
fifth transmembrane regions and the second is in the C-terminal section.
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