Dehydrogenase/reductase (SDR family) X-linked also known as DHRSX is an

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

which in humans is encoded by the

pseudoautosomal The pseudoautosomal regions or PARs are homologous sequences of nucleotides found within the sex chromosomes of species with an XY or ZW mechanism of sex determination. The pseudoautosomal regions get their name because any genes within them ...

''DHRSX''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

. DHRSX is a member of the

short-chain dehydrogenase The short-chain dehydrogenases/reductases family (SDR) is a very large family of enzymes, most of which are known to be NAD- or NADP-dependent oxidoreductases. As the first member of this family to be characterised was Drosophila alcohol dehydroge ...

family of

oxidoreductase In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually ut ...

enzymes. DHRSX is required for two steps in the biosynthesis of

dolichol Dolichol refers to any of a group of long-chain mostly unsaturated organic compounds that are made up of varying numbers of isoprene units terminating in an α-saturated isoprenoid group, containing an alcohol functional group. Functions Dolicho ...

: i) the NAD⁺-dependent conversion of polyprenol to its aldehyde analogue, polyprenal; ii) the NADPH-dependent reduction of dolichal to dolichol. Dolichol is a long polyisoprenoid lipid required as the carrier of mono- and oligosaccharides in the processes of

N-glycosylation ''N''-linked glycosylation is the attachment of an oligosaccharide, a carbohydrate consisting of several sugar molecules, sometimes also referred to as glycan, to a nitrogen atom (the amide nitrogen of an asparagine (Asn) residue of a protein), i ...

, C-/O-mannosylation and the formation of glycosylphosphatidylinositol (GPI) anchors.

References

Further reading