UniProt functional annotation for P01023



	UniProt functional annotation for P01023

UniProt code: P01023.

Organism: Homo sapiens (Human).

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

Function: Is able to inhibit all four classes of proteinases by a unique 'trapping' mechanism. This protein has a peptide stretch, called the 'bait region' which contains specific cleavage sites for different proteinases. When a proteinase cleaves the bait region, a conformational change is induced in the protein which traps the proteinase. The entrapped enzyme remains active against low molecular weight substrates (activity against high molecular weight substrates is greatly reduced). Following cleavage in the bait region, a thioester bond is hydrolyzed and mediates the covalent binding of the protein to the proteinase.

Subunit: Homotetramer; disulfide-linked. {ECO:0000269|PubMed:2430963, ECO:0000269|PubMed:6203908}.

Subcellular location: Secreted {ECO:0000269|PubMed:6203908}.

Tissue specificity: Secreted in plasma. {ECO:0000269|PubMed:6203908}.

Developmental stage: Unlike the rat protein, which is an acute phase protein, this protein is always in circulation at high levels.

Similarity: Belongs to the protease inhibitor I39 (alpha-2- macroglobulin) family. {ECO:0000305}.

Sequence caution: Sequence=AAT02228.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305}; Sequence=BAD92851.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305};

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:		Is able to inhibit all four classes of proteinases by a unique 'trapping' mechanism. This protein has a peptide stretch, called the 'bait region' which contains specific cleavage sites for different proteinases. When a proteinase cleaves the bait region, a conformational change is induced in the protein which traps the proteinase. The entrapped enzyme remains active against low molecular weight substrates (activity against high molecular weight substrates is greatly reduced). Following cleavage in the bait region, a thioester bond is hydrolyzed and mediates the covalent binding of the protein to the proteinase.


Subunit:		Homotetramer; disulfide-linked. {ECO:0000269\|PubMed:2430963, ECO:0000269\|PubMed:6203908}.
Subcellular location:		Secreted {ECO:0000269\|PubMed:6203908}.
Tissue specificity:		Secreted in plasma. {ECO:0000269\|PubMed:6203908}.
Developmental stage:		Unlike the rat protein, which is an acute phase protein, this protein is always in circulation at high levels.
Similarity:		Belongs to the protease inhibitor I39 (alpha-2- macroglobulin) family. {ECO:0000305}.
Sequence caution:		Sequence=AAT02228.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305}; Sequence=BAD92851.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305};