P62744 (AP2S1_RAT) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
AP-2 complex subunit sigma

Alternative name(s):
Adapter-related protein complex 2 sigma subunit
Adaptor protein complex AP-2 subunit sigma
Clathrin assembly protein 2 small chain
Clathrin coat assembly protein AP17
Clathrin coat-associated protein AP17
Plasma membrane adaptor AP-2 17 kDa protein
Sigma-adaptin 3b
Sigma2-adaptin

Gene names

Name:	Ap2s1
Synonyms:	Ap17, Claps2

Organism

Rattus norvegicus (Rat) [Reference proteome]

Taxonomic identifier

10116 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus

Protein attributes

Sequence length	142 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Component of the adaptor protein complex 2 (AP-2). Adaptor protein complexes function in protein Transport via Transport vesicles in different membrane traffic pathways. Adaptor protein complexes are vesicle coat components and appear to be involved in cargo selection and vesicle formation. AP-2 is involved in clathrin-dependent endocytosis in which cargo proteins are incorporated into vesicles surrounded by clathrin (clathrin-coated vesicles, CCVs) which are destined for fusion with the early endosome. The clathrin lattice serves as a mechanical scaffold but is itself unable to bind directly to membrane components. Clathrin-associated adaptor protein (AP) complexes which can bind directly to both the clathrin lattice and to the lipid and protein components of membranes are considered to be the major clathrin adaptors contributing the CCV formation. AP-2 also serves as a cargo receptor to selectively sort the membrane proteins involved in receptor-mediated endocytosis. AP-2 seems to play a role in the recycling of synaptic vesicle membranes from the presynaptic surface. AP-2 recognizes Y-X-X-[FILMV] (Y-X-X-Phi) and [ED]-X-X-X-L-[LI] endocytosis signal motifs within the cytosolic tails of transmembrane cargo molecules. AP-2 may also play a role in maintaining normal post-endocytic trafficking through the ARF6-regulated, non-clathrin pathway. The AP-2 alpha and AP-2 sigma subunits are thought to contribute to the recognition of the [ED]-X-X-X-L-[LI] motif By similarity. Ref.4 Ref.5
Subunit structure	Adaptor protein complex 2 (AP-2) is a heterotetramer composed of two large adaptins (alpha-type subunit AP2A1 or AP2A2 and beta-type subunit AP2B1), a medium adaptin (mu-type subunit AP2M1) and a small adaptin (sigma-type subunit AP2S1) By similarity.
Subcellular location	Cell membrane. Membrane › coated pit; Peripheral membrane protein; Cytoplasmic side. Note: AP-2 appears to be excluded from internalizing CCVs and to disengage from sites of endocytosis seconds before internalization of the nascent CCV By similarity.
Sequence similarities	Belongs to the adaptor complexes small subunit family.

Ontologies

Keywords
Biological process	Protein transport Transport
Cellular component	Cell membrane Coated pit Membrane
PTM	Phosphoprotein
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	intracellular protein transport Inferred from electronic annotation. Source: InterPro vesicle-mediated transport Inferred from electronic annotation. Source: InterPro
Cellular_component	AP-1 adaptor complex Traceable author statement Ref.1. Source: RGD AP-2 adaptor complex Inferred from direct assay Ref.1. Source: MGI
Molecular_function	protein transporter activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 142	142	AP-2 complex subunit sigma		PRO_0000193807
Amino acid modifications
	Modified residue	140	1	Phosphoserine By similarity
Experimental info
	Sequence conflict	83	1	A → G in AAB46980. Ref.2
	Sequence conflict	109 – 110	2	KV → RF in AAB46980. Ref.2
	Sequence conflict	117	1	M → I in AAB46980. Ref.2
	Sequence conflict	126	1	T → R in AAB46980. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	P62744 [UniParc]. Last modified August 16, 2004. Version 1. Checksum: CA3FD868C65AEDF6	FASTA	142	17,018
	10 20 30 40 50 60 MIRFILIQNR AGKTRLAKWY MQFDDDEKQK LIEEVHAVVT VRDAKHTNFV EFRNFKIIYR 70 80 90 100 110 120 RYAGLYFCIC VDVNDNNLAY LEAIHNFVEV LNEYFHNVCE LDLVFNFYKV YTVVDEMFLA 130 140 GEIRETSQTK VLKQLLMLQS LE

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"AP17 and AP19, the mammalian small chains of the clathrin-associated protein complexes show homology to Yap17p, their putative homolog in yeast." Kirchhausen T., Davis A.C., Frucht S., O'Brine Greco B., Payne G.S., Tubb B. J. Biol. Chem. 266:11153-11157(1991) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Brain.
[2]	"A systematic analysis of 40 random genes in cultured vascular smooth muscle subtypes reveals a heterogeneity of gene expression and identifies the tight junction gene zonula occludens 2 as a marker of epithelioid 'pup' smooth muscle cells and a participant in carotid neointimal formation." Adams L.D., Lemire J.M., Schwartz S.M. Arterioscler. Thromb. Vasc. Biol. 19:2600-2608(1999) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: Wistar Kyoto.
[3]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Tissue: Spleen.
[4]	"Adaptor protein complexes as the key regulators of protein sorting in the post-Golgi network." Nakatsu F., Ohno H. Cell Struct. Funct. 28:419-429(2003) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF THE AP-2 COMPLEX IN CLATHRIN-MEDIATED ENDOCYTOSIS.
[5]	"Adaptors for clathrin coats: structure and function." Owen D.J., Collins B.M., Evans P.R. Annu. Rev. Cell Dev. Biol. 20:153-191(2004) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION OF THE AP-2 COMPLEX IN CLATHRIN-MEDIATED ENDOCYTOSIS.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	M37194 mRNA. Translation: AAA40742.1. U75917 mRNA. Translation: AAB46980.1. BC088138 mRNA. Translation: AAH88138.1.
IPI	IPI00198371.
PIR	B40535.
RefSeq	NP_075241.2. NM_022952.2.
UniGene	Rn.37866.
3D structure databases
ProteinModelPortal	P62744.
ModBase	Search...
Proteomic databases
PaxDb	P62744.
PRIDE	P62744.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENSRNOT00000021310; ENSRNOP00000021310; ENSRNOG00000015865.
GeneID	65046.
KEGG	rno:65046.
UCSC	RGD:620188. rat.
Organism-specific databases
CTD	1175.
RGD	620188. Ap2s1.
Phylogenomic databases
eggNOG	COG5030.
GeneTree	ENSGT00530000062839.
HOGENOM	HOG000185227.
HOVERGEN	HBG050517.
InParanoid	P62744.
KO	K11827.
OMA	VAPRDQK.
OrthoDB	EOG4J119F.
Enzyme and pathway databases
Reactome	REACT_111984. Signal Transduction.
Gene expression databases
Genevestigator	P62744.
GermOnline	ENSRNOG00000015865. Rattus norvegicus.
Family and domain databases
InterPro	IPR016635. AP_complex_ssu. IPR022775. AP_mu_sigma_su. IPR027156. APS2. IPR000804. Clathrin_sm-chain_CS. IPR011012. Longin-like_dom. [Graphical view]
PANTHER	PTHR11753. PTHR11753. 1 hit. PTHR11753:SF6. PTHR11753:SF6. 1 hit.
Pfam	PF01217. Clat_adaptor_s. 1 hit. [Graphical view]
PIRSF	PIRSF015588. AP_complex_sigma. 1 hit.
SUPFAM	SSF64356. Longin_like. 1 hit.
PROSITE	PS00989. CLAT_ADAPTOR_S. 1 hit. [Graphical view]
ProtoNet	Search...
Other
BindingDB	P62744.
ChEMBL	CHEMBL1697667.
NextBio	381325.

Entry information

Entry name

AP2S1_RAT

Accession

Primary (citable) accession number: P62744
Secondary accession number(s): P70626, P97626, Q00380

Entry history

Integrated into UniProtKB/Swiss-Prot:	August 16, 2004
Last sequence update:	August 16, 2004
Last modified:	May 1, 2013
This is version 70 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program