go_id,ontology,go_term,term_definition,evidence
GO:0000139,CC,"Golgi membrane","The lipid bilayer surrounding any of the compartments of the Golgi apparatus.",IEA
GO:0004653,MF,"polypeptide N-acetylgalactosaminyltransferase activity","Catalysis of the reaction: UDP-N-acetyl-D-galactosamine + polypeptide = UDP + N-acetyl-D-galactosaminyl-polypeptide. This reaction is the modification of serine or threonine residues in polypeptide chains by the transfer of a N-acetylgalactose from UDP-N-acetylgalactose to the hydroxyl group of the amino acid; it is the first step in O-glycan biosynthesis.",IDA|TAS
GO:0005975,BP,"carbohydrate metabolic process","The chemical reactions and pathways involving carbohydrates, any of a group of organic compounds based of the general formula Cx(H2O)y. Includes the formation of carbohydrate derivatives by the addition of a carbohydrate residue to another molecule.",TAS
GO:0006493,BP,"protein O-linked glycosylation","A protein glycosylation process in which a carbohydrate or carbohydrate derivative unit is added to a protein via the hydroxyl group of peptidyl-serine, peptidyl-threonine, peptidyl-hydroxylysine, or peptidyl-hydroxyproline, or via the phenol group of peptidyl-tyrosine, forming an O-glycan.",IDA|IMP
GO:0016020,CC,membrane,"A lipid bilayer along with all the proteins and protein complexes embedded in it an attached to it.",IDA
GO:0016021,CC,"integral component of membrane","The component of a membrane consisting of the gene products and protein complexes having at least some part of their peptide sequence embedded in the hydrophobic region of the membrane.",IEA
GO:0016266,BP,"O-glycan processing","The stepwise addition of carbohydrate or carbohydrate derivative residues to the initially added O-linked residue (usually GalNAc) to form a core O-glycan structure.",TAS
GO:0030246,MF,"carbohydrate binding","Interacting selectively and non-covalently with any carbohydrate, which includes monosaccharides, oligosaccharides and polysaccharides as well as substances derived from monosaccharides by reduction of the carbonyl group (alditols), by oxidation of one or more hydroxy groups to afford the corresponding aldehydes, ketones, or carboxylic acids, or by replacement of one or more hydroxy group(s) by a hydrogen atom. Cyclitols are generally not regarded as carbohydrates.",IDA
GO:0046872,MF,"metal ion binding","Interacting selectively and non-covalently with any metal ion.",IEA
GO:0070062,CC,"extracellular exosome","A membrane-bounded vesicle that is released into the extracellular region by fusion of the limiting endosomal membrane of a multivesicular body with the plasma membrane. Extracellular exosomes, also simply called exosomes, have a diameter of about 40-100 nm.",IDA