Interleukin-36 gamma previously known as interleukin-1 family member 9 (IL1F9) is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
that in humans is encoded by the ''IL36G''
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 ba ...
.
Expression
''IL36G'' is well-expressed in the epithelium of the skin, gut, and lung. In the skin ''IL36G'' is predominantly expressed in epidermal granular layer keratinocytes with little to no expression in basal layer keratinocytes.
Function
The protein encoded by this gene is a member of the
interleukin-1
The Interleukin-1 family (IL-1 family) is a group of 11 cytokines that plays a central role in the regulation of immune and inflammatory responses to infections or sterile insults.
Discovery
Discovery of these cytokines began with studies on t ...
cytokine
Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...
family. This gene and eight other interleukin-1 family genes form a cytokine gene cluster on chromosome 2. The activity of this cytokine is mediated via the interleukin-1 receptor-like 2 (
IL1RL2
Interleukin-1 receptor-like 2 is a protein that in humans is encoded by the ''IL1RL2'' gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation ...
/IL1R-rp2/IL-36 receptor), and is specifically inhibited by interleukin-36 receptor antagonist, (
IL-36RA
Interleukin 36 receptor antagonist (IL-36RA) is a member of the interleukin-36 family of cytokines. It was previously named Interleukin-1 family member 5 (IL1F5).
The protein is known to inhibit the effects of Interleukin-36 cytokines (IL36A, IL- ...
/IL1F5/IL-1 delta).
Interferon-gamma
Interferon gamma (IFN-γ) is a dimerized soluble cytokine that is the only member of the type II class of interferons. The existence of this interferon, which early in its history was known as immune interferon, was described by E. F. Wheelock ...
,
tumor necrosis factor-alpha
Tumor necrosis factor (TNF, cachexin, or cachectin; formerly known as tumor necrosis factor alpha or TNF-α) is an adipokine and a cytokine. TNF is a member of the TNF superfamily, which consists of various transmembrane proteins with a homolog ...
and interleukin-1 β (
IL-1β
Interleukin-1 beta (IL-1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the ''IL1B'' gene."Catabolin" ...
) are reported to stimulate the expression of this cytokine in
keratinocyte
Keratinocytes are the primary type of Cell (biology), cell found in the epidermis (skin), epidermis, the outermost layer of the skin. In humans, they constitute 90% of epidermal skin cells.
Basal cells in the stratum basale, basal layer (''str ...
s. The expression of this cytokine in keratinocytes can also be induced by a multiple Pathogen-Associated Molecular Patterns (
PAMPs
Pathogen-associated molecular patterns (PAMPs) are small molecular motifs conserved within a class of microbes. They are recognized by toll-like receptors (TLRs) and other pattern recognition receptors (PRRs) in both plants and animals. A vast arra ...
). Both IL-36γ mRNA and protein have been linked to psoriasis lesions and has been used as a biomarker for differentiating between eczema and psoriasis. As with many other interleukin-1 family cytokines IL-36γ requires proteolytic cleavage of its N-terminus for full biological activity. However, unlike IL-1β the activation of IL-36γ is
inflammasome
Inflammasomes are cytosolic multiprotein oligomers of the innate immune system responsible for the activation of inflammatory responses. Activation and assembly of the inflammasome promotes proteolytic cleavage, maturation and secretion of pro-in ...
-independent. IL-36γ is specifically cleaved by the endogenous protease
cathepsin S
Cathepsin S is a protein that in humans is encoded by the ''CTSS'' gene. Transcript variants utilizing alternative polyadenylation signals exist for this gene.
Cathepsin S is a member of the peptidase C1 family of cysteine cathepsins, a lysosomal ...
as well exogenous proteases derived from fungal and bacterial pathogens.
References
Biomarkers
Further reading
*
*
*
*
*
*
*
*
*
*
*
*
{{gene-2-stub