UniProt functional annotation for O43918



	UniProt functional annotation for O43918

UniProt code: O43918.

Organism: Homo sapiens (Human).

Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.

Function: Transcription factor playing an essential role to promote self-tolerance in the thymus by regulating the expression of a wide array of self-antigens that have the commonality of being tissue- restricted in their expression pattern in the periphery, called tissue restricted antigens (TRA) (PubMed:26084028). Binds to G-doublets in an A/T-rich environment; the preferred motif is a tandem repeat of 5'- ATTGGTTA-3' combined with a 5'-TTATTA-3' box. Binds to nucleosomes (By similarity). Binds to chromatin and interacts selectively with histone H3 that is not methylated at 'Lys-4', not phosphorylated at 'Thr-3' and not methylated at 'Arg-2'. Functions as a sensor of histone H3 modifications that are important for the epigenetic regulation of gene expression. Mainly expressed by medullary thymic epithelial cells (mTECs), induces the expression of thousands of tissue-restricted proteins, which are presented on major histocompatibility complex class I (MHC-I) and MHC-II molecules to developing T-cells percolating through the thymic medulla (PubMed:26084028). Also induces self- tolerance through other mechanisms such as the regulation of the mTEC differentiation program. Controls the medullary accumulation of thymic dendritic cells and the development of regulatory T-cell through the regulation of XCL1 expression. Regulates the production of CCR4 and CCR7 ligands in medullary thymic epithelial cells and alters the coordinated maturation and migration of thymocytes. In thimic B-cells, allows the presentation of licensing-dependent endogenous self-anitgen for negative selection. In secondary lymphoid organs, induces functional inactivation of CD4(+) T-cells. Expressed by a distinct bone marrow-derived population, induces self-tolerance through a mechanism that does not require regulatory T-cells and is resitant to innate inflammatory stimuli (By similarity). {ECO:0000250|UniProtKB:Q9Z0E3, ECO:0000269|PubMed:11274163, ECO:0000269|PubMed:18292755, ECO:0000269|PubMed:26084028, ECO:0000305|PubMed:19302042, ECO:0000305|PubMed:26972725}.

Subunit: Homodimer and homotetramer. Interacts with CREBBP. Interacts preferentially with histone H3 that is not methylated at 'Lys-4'. Binds with lower affinity to histone H3 that is monomethylated at 'Lys-4'. Trimethylation of histone H3 at 'Lys-4' or phosphorylation at 'Thr-3' abolish the interaction. Binds with lower affinity to histone H3 that is acetylated at 'Lys-4', or that is acetylated at 'Lys-9' or trimethylated at 'Lys-9'. Binds histone H3 that is dimethylated at 'Arg-2' with very low affinity. {ECO:0000269|PubMed:11533054, ECO:0000269|PubMed:15649886, ECO:0000269|PubMed:18292755, ECO:0000269|PubMed:19293276, ECO:0000269|PubMed:19446523}.

Subcellular location: Nucleus {ECO:0000269|PubMed:14974083, ECO:0000269|PubMed:26084028}. Cytoplasm {ECO:0000269|PubMed:11274163, ECO:0000269|PubMed:14974083}. Note=Predominantly nuclear but also cytoplasmic (PubMed:11274163, PubMed:14974083). Found in nuclear body- like structures (dots) and in a filamentous vimentin-like pattern (PubMed:11274163, PubMed:14974083, PubMed:26084028). Associated with tubular structures (PubMed:11274163, PubMed:14974083). {ECO:0000269|PubMed:11274163, ECO:0000269|PubMed:14974083, ECO:0000269|PubMed:26084028}.

Tissue specificity: Widely expressed. Expressed at higher level in thymus (medullary epithelial cells and monocyte-dendritic cells), pancreas, adrenal cortex and testis. Expressed at lower level in the spleen, fetal liver and lymph nodes. In secondary lymphoid organs, expressed in a discrete population of bone marrow-derived toleregenic antigen presenting cells (APCs) called extrathymic AIRE expressing cells (eTAC)(at protein level) (PubMed:23993652). Isoform 2 and isoform 3 seem to be less frequently expressed than isoform 1, if at all. {ECO:0000269|PubMed:23993652}.

Domain: The L-X-X-L-L repeats may be implicated in binding to nuclear receptors.

Domain: The HSR domain is required for localization on tubular structures (N-terminal part) and for homodimerization.

Domain: Interacts via the first PHD domain with the N-terminus of histone H3 that is not methylated at 'Lys-4'. Disruption of the first PHD domain has been shown to lead to reduced transcriptional activity and to localization of the protein mainly in the cytoplasm in small granules. While the PHD zinc fingers are necessary for the transactivation capacity of the protein, other regions also modulate this function.

Ptm: Phosphorylated. Phosphorylation could trigger oligomerization. {ECO:0000269|PubMed:11533054}.

Disease: Autoimmune polyendocrine syndrome 1, with or without reversible metaphyseal dysplasia (APS1) [MIM:240300]: A rare disease characterized by the combination of chronic mucocutaneous candidiasis, hypoparathyroidism and Addison disease. Symptoms of mucocutaneous candidiasis manifest first, followed by hypotension or fatigue occurring as a result of Addison disease. APS1 is associated with other autoimmune disorders including diabetes mellitus, vitiligo, alopecia, hepatitis, pernicious anemia and primary hypothyroidism. {ECO:0000269|PubMed:10677297, ECO:0000269|PubMed:11274163, ECO:0000269|PubMed:11275943, ECO:0000269|PubMed:11524731, ECO:0000269|PubMed:11524733, ECO:0000269|PubMed:11600535, ECO:0000269|PubMed:11836330, ECO:0000269|PubMed:12050215, ECO:0000269|PubMed:12173302, ECO:0000269|PubMed:12625412, ECO:0000269|PubMed:14974083, ECO:0000269|PubMed:15649886, ECO:0000269|PubMed:15712268, ECO:0000269|PubMed:16114041, ECO:0000269|PubMed:18292755, ECO:0000269|PubMed:19446523, ECO:0000269|PubMed:26084028, ECO:0000269|PubMed:27426947, ECO:0000269|PubMed:9398839, ECO:0000269|PubMed:9888391}. Note=The disease is caused by variants affecting the gene represented in this entry. Most of the mutations alter the nucleus-cytoplasm distribution of AIRE and disturb its association with nuclear dots and cytoplasmic filaments. Most of the mutations also decrease transactivation of the protein. The HSR domain is responsible for the homomultimerization activity of AIRE. All the missense mutations of the HSR and the SAND domains decrease this activity, but those in other domains do not. The AIRE protein is present in soluble high-molecular-weight complexes. Mutations in the HSR domain and deletion of PHD zinc fingers disturb the formation of these complexes (PubMed:14974083). Heterozygous mutations within the PHD1 domain have dominant-negatif effects and cause organ-specific autoimmune diseases (PubMed:26084028). Patients harbor extremely high-affinity, neutralizing autoantibodies, particularly against specific cytokines such as type I interferons which could protect them from some types of autoimmune diseases, like type I diabetes (PubMed:27426947). {ECO:0000269|PubMed:14974083, ECO:0000269|PubMed:26084028, ECO:0000269|PubMed:27426947}.

Annotations taken from UniProtKB at the EBI.


Organism:		Homo sapiens (Human).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.



Function:		Transcription factor playing an essential role to promote self-tolerance in the thymus by regulating the expression of a wide array of self-antigens that have the commonality of being tissue- restricted in their expression pattern in the periphery, called tissue restricted antigens (TRA) (PubMed:26084028). Binds to G-doublets in an A/T-rich environment; the preferred motif is a tandem repeat of 5'- ATTGGTTA-3' combined with a 5'-TTATTA-3' box. Binds to nucleosomes (By similarity). Binds to chromatin and interacts selectively with histone H3 that is not methylated at 'Lys-4', not phosphorylated at 'Thr-3' and not methylated at 'Arg-2'. Functions as a sensor of histone H3 modifications that are important for the epigenetic regulation of gene expression. Mainly expressed by medullary thymic epithelial cells (mTECs), induces the expression of thousands of tissue-restricted proteins, which are presented on major histocompatibility complex class I (MHC-I) and MHC-II molecules to developing T-cells percolating through the thymic medulla (PubMed:26084028). Also induces self- tolerance through other mechanisms such as the regulation of the mTEC differentiation program. Controls the medullary accumulation of thymic dendritic cells and the development of regulatory T-cell through the regulation of XCL1 expression. Regulates the production of CCR4 and CCR7 ligands in medullary thymic epithelial cells and alters the coordinated maturation and migration of thymocytes. In thimic B-cells, allows the presentation of licensing-dependent endogenous self-anitgen for negative selection. In secondary lymphoid organs, induces functional inactivation of CD4(+) T-cells. Expressed by a distinct bone marrow-derived population, induces self-tolerance through a mechanism that does not require regulatory T-cells and is resitant to innate inflammatory stimuli (By similarity). {ECO:0000250\|UniProtKB:Q9Z0E3, ECO:0000269\|PubMed:11274163, ECO:0000269\|PubMed:18292755, ECO:0000269\|PubMed:26084028, ECO:0000305\|PubMed:19302042, ECO:0000305\|PubMed:26972725}.


Subunit:		Homodimer and homotetramer. Interacts with CREBBP. Interacts preferentially with histone H3 that is not methylated at 'Lys-4'. Binds with lower affinity to histone H3 that is monomethylated at 'Lys-4'. Trimethylation of histone H3 at 'Lys-4' or phosphorylation at 'Thr-3' abolish the interaction. Binds with lower affinity to histone H3 that is acetylated at 'Lys-4', or that is acetylated at 'Lys-9' or trimethylated at 'Lys-9'. Binds histone H3 that is dimethylated at 'Arg-2' with very low affinity. {ECO:0000269\|PubMed:11533054, ECO:0000269\|PubMed:15649886, ECO:0000269\|PubMed:18292755, ECO:0000269\|PubMed:19293276, ECO:0000269\|PubMed:19446523}.
Subcellular location:		Nucleus {ECO:0000269\|PubMed:14974083, ECO:0000269\|PubMed:26084028}. Cytoplasm {ECO:0000269\|PubMed:11274163, ECO:0000269\|PubMed:14974083}. Note=Predominantly nuclear but also cytoplasmic (PubMed:11274163, PubMed:14974083). Found in nuclear body- like structures (dots) and in a filamentous vimentin-like pattern (PubMed:11274163, PubMed:14974083, PubMed:26084028). Associated with tubular structures (PubMed:11274163, PubMed:14974083). {ECO:0000269\|PubMed:11274163, ECO:0000269\|PubMed:14974083, ECO:0000269\|PubMed:26084028}.
Tissue specificity:		Widely expressed. Expressed at higher level in thymus (medullary epithelial cells and monocyte-dendritic cells), pancreas, adrenal cortex and testis. Expressed at lower level in the spleen, fetal liver and lymph nodes. In secondary lymphoid organs, expressed in a discrete population of bone marrow-derived toleregenic antigen presenting cells (APCs) called extrathymic AIRE expressing cells (eTAC)(at protein level) (PubMed:23993652). Isoform 2 and isoform 3 seem to be less frequently expressed than isoform 1, if at all. {ECO:0000269\|PubMed:23993652}.
Domain:		The L-X-X-L-L repeats may be implicated in binding to nuclear receptors.
Domain:		The HSR domain is required for localization on tubular structures (N-terminal part) and for homodimerization.
Domain:		Interacts via the first PHD domain with the N-terminus of histone H3 that is not methylated at 'Lys-4'. Disruption of the first PHD domain has been shown to lead to reduced transcriptional activity and to localization of the protein mainly in the cytoplasm in small granules. While the PHD zinc fingers are necessary for the transactivation capacity of the protein, other regions also modulate this function.
Ptm:		Phosphorylated. Phosphorylation could trigger oligomerization. {ECO:0000269\|PubMed:11533054}.
Disease:		Autoimmune polyendocrine syndrome 1, with or without reversible metaphyseal dysplasia (APS1) [MIM:240300]: A rare disease characterized by the combination of chronic mucocutaneous candidiasis, hypoparathyroidism and Addison disease. Symptoms of mucocutaneous candidiasis manifest first, followed by hypotension or fatigue occurring as a result of Addison disease. APS1 is associated with other autoimmune disorders including diabetes mellitus, vitiligo, alopecia, hepatitis, pernicious anemia and primary hypothyroidism. {ECO:0000269\|PubMed:10677297, ECO:0000269\|PubMed:11274163, ECO:0000269\|PubMed:11275943, ECO:0000269\|PubMed:11524731, ECO:0000269\|PubMed:11524733, ECO:0000269\|PubMed:11600535, ECO:0000269\|PubMed:11836330, ECO:0000269\|PubMed:12050215, ECO:0000269\|PubMed:12173302, ECO:0000269\|PubMed:12625412, ECO:0000269\|PubMed:14974083, ECO:0000269\|PubMed:15649886, ECO:0000269\|PubMed:15712268, ECO:0000269\|PubMed:16114041, ECO:0000269\|PubMed:18292755, ECO:0000269\|PubMed:19446523, ECO:0000269\|PubMed:26084028, ECO:0000269\|PubMed:27426947, ECO:0000269\|PubMed:9398839, ECO:0000269\|PubMed:9888391}. Note=The disease is caused by variants affecting the gene represented in this entry. Most of the mutations alter the nucleus-cytoplasm distribution of AIRE and disturb its association with nuclear dots and cytoplasmic filaments. Most of the mutations also decrease transactivation of the protein. The HSR domain is responsible for the homomultimerization activity of AIRE. All the missense mutations of the HSR and the SAND domains decrease this activity, but those in other domains do not. The AIRE protein is present in soluble high-molecular-weight complexes. Mutations in the HSR domain and deletion of PHD zinc fingers disturb the formation of these complexes (PubMed:14974083). Heterozygous mutations within the PHD1 domain have dominant-negatif effects and cause organ-specific autoimmune diseases (PubMed:26084028). Patients harbor extremely high-affinity, neutralizing autoantibodies, particularly against specific cytokines such as type I interferons which could protect them from some types of autoimmune diseases, like type I diabetes (PubMed:27426947). {ECO:0000269\|PubMed:14974083, ECO:0000269\|PubMed:26084028, ECO:0000269\|PubMed:27426947}.