Alpha-1-acid glycoprotein (IPR001500)

Short name: A1A_glycop

Overlapping homologous superfamilies

Family relationships



The name 'lipocalin' has been proposed [PMID: 3622999] for the larger protein family, but cytosolic fatty-acid binding proteins are also included. The sequences of most members of the family, the core or kernal lipocalins, are characterised by three short conserved stretches of residues, while others, the outlier lipocalin group, share only one or two of these [PMID: 1834059, PMID: 7684291]. Proteins known to belong to this family include alpha-1-microglobulin (protein HC); alpha-1-acid glycoprotein (orosomucoid) [PMID: 3064105]; aphrodisin; apolipoprotein D; beta-lactoglobulin; complement component C8 gamma chain [PMID: 1707134]; crustacyanin [PMID: 2026162]; epididymal-retinoic acid binding protein (E-RABP) [PMID: 8069623]; insectacyanin; odorant-binding protein (OBP); human pregnancy-associated endometrial alpha-2 globulin; probasin (PB), a rat prostatic protein; prostaglandin D synthase EC: [PMID: 1723819]; purpurin; Von Ebner's gland protein (VEGP) [PMID: 7514123]; and Lacerta vivipara (Common lizard) epididymal secretory protein IV (LESP IV) [PMID: 8486691].

Alpha-1-acid glycoprotein (orosomucin) (A1AG) is a major serum glycoprotein of unknown physiological function [PMID: 7866554]. It has been implicated in cellular inflammation by increasing tissue factor expression and tumour necrosis factor alpha secretion of monocytes. The protein is associated with five asparaginyl-linked complex oligosaccaride chains, the proportions and identities of which are altered in several physiological and pathological conditions [PMID: 8886858]. A1AG is also clinically important as a non-specific drug binder in serum [PMID: 3064105]. It has recently been shown to bind to thalidomide, which may be involved in its inhibition of tumor necrosis factor alpha production [PMID: 8755512].

GO terms

Biological Process

GO:0002682 regulation of immune system process

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0005615 extracellular space

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.