4,4-dimethylcholesta-8(9),14,24-trien-3beta-ol is reduced to 4,4-dimethylcholesta-8(9),24-dien-3beta-ol [TM7SF2]

Stable Identifier
R-HSA-194698
Type
Reaction [transition]
Species
Homo sapiens
Compartment
Synonyms
4,4-dimethylcholesta-8(9),14,24-trien-3beta-ol + NADPH + H+ => 4,4-dimethylcholesta-8(9),24-dien-3beta-ol + NADP+ [TM7SF2]
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4,4-dimethylcholesta-8(9),14,24-trien-3beta-ol and NADPH + H+ react to form 4,4-dimethylcholesta-8(9),24-dien-3beta-ol and NADP+, catalyzed by TM7SF2 in the endoplasmic reticulum. TM7SF2 protein has sterol delta14-reductase activity in vitro, and expression of the gene is induced by sterol starvation in human cells, as expected for a gene involved in sterol biosynthesis (Bennati et al. 2006). However, molecular studies of material from an individual with HEM/Greenberg skeletal dysplasia indicate that LBR, a protein that spans the inner nuclear membrane and has both laminin receptor and sterol delta14-reductase activities, is required for normal sterol 14delta-reductase activity in human cells. It remains to be determined whether both LBR and TM7SF2 catalyze this reaction in vivo, and whether the role of TM7SF2 is essential (Waterham et al. 2003).

Literature References
PubMed ID Title Journal Year
16784888 Sterol dependent regulation of human TM7SF2 gene expression: role of the encoded 3beta-hydroxysterol Delta14-reductase in human cholesterol biosynthesis

Bennati, AM, Castelli, M, Della Fazia, MA, Beccari, T, Caruso, D, Servillo, G, Roberti, R

Biochim Biophys Acta 2006
Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
delta14-sterol reductase activity of TM7SF2 [endoplasmic reticulum membrane]
Physical Entity
Activity
Orthologous Events
Authored
Reviewed
Created