Membrane-bound transcription factor site-2 protease, also known as S2P endopeptidase or site-2 protease (S2P), is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

() encoded by the

gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

which liberates the N-terminal fragment of

sterol regulatory element-binding protein Sterol regulatory element-binding proteins (SREBPs) are transcription factors that bind to the sterol regulatory element DNA sequence TCACNCCAC. Mammalian SREBPs are encoded by the genes ''SREBF1'' and '' SREBF2''. SREBPs belong to the basic- ...

(SREBP)

transcription factor In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The f ...

s from membranes. S2P cleaves the

transmembrane domain A transmembrane domain (TMD) is a membrane-spanning protein domain. TMDs generally adopt an alpha helix topological conformation, although some TMDs such as those in porins can adopt a different conformation. Because the interior of the lipid bi ...

of SREPB, making it a member of the class of

intramembrane protease Intramembrane proteases (IMPs), also known as intramembrane-cleaving proteases (I-CLiPs), are enzymes that have the property of cleaving transmembrane domains of integral membrane proteins. All known intramembrane proteases are themselves integral ...

s. S2P catalyses the following

chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...

: Cleaves several

s that are type-2

transmembrane protein A transmembrane protein (TP) is a type of integral membrane protein that spans the entirety of the cell membrane. Many transmembrane proteins function as gateways to permit the transport of specific substances across the membrane. They frequent ...

s within membrane-spanning domains. Known substrates include

(SREBP)-1, SREBP-2 and forms of the

transcriptional activator A transcriptional activator is a protein (transcription factor) that increases transcription of a gene or set of genes. Activators are considered to have ''positive'' control over gene expression, as they function to promote gene transcription and ...

ATF6. This enzyme belongs to the peptidase family M50.

Function

This gene encodes an intramembrane zinc

metalloprotease A metalloproteinase, or metalloprotease, is any protease enzyme whose catalytic mechanism involves a metal. An example is ADAM12 which plays a significant role in the fusion of muscle cells during embryo development, in a process known as myo ...

, which is essential in development. This

protease A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the ...

functions in the signal protein activation involved in sterol control of transcription and the ER stress response. Mutations in this gene have been associated with ichthyosis follicularis with atrichia and photophobia (

IFAP syndrome IFAP syndrome is an extremely rare genetic syndrome. It is also known as Ichthyosis follicularis, alopecia, and photophobia syndrome or simply ichthyosis follicularis.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the ...

); IFAP syndrome has been quantitatively linked to a reduction in

cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell mem ...

homeostasis and ER stress response. rovided by RefSeq, Aug 2009

References

External links

* * EC 3.4.24 {{gene-X-stub

Function

See also

References

External links