17-Beta-Hydroxysteroid Dehydrogenase Type 12 (HSD17b12)

HSD17B12 uses NADPH to reduce 3-ketoacyl-CoA to 3-hydroxyacyl-CoA during the second step of fatty acid elongation.The human HSD17B12 gene encodes a protein of 312 amino acids containing a dilysine endoplasmic reticulum (ER)-retention motif at the C terminus and 4 predicted transmembrane domains. Mouse and human HSD17B12 share 82% amino acid identity. Northern blot analysis showed expression of a 2.9-kb HSD17B12 transcript in all human tissues tested, with highest levels seen in liver, muscle, and kidney. Analysis of liver HSD17B12 mRNA in transgenic mice with altered levels of sterol regulatory element-binding proteins (SREBPs) showed no change in HSD17B12 expression compared to wildtype mice, suggesting that HSD17B12 is not regulated by SREBPs.