Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Gene Ontology annotation based on curation of immunofluorescence data
Automatic transfer of experimentally verified manual GO annotation data to orthologs using Ensembl Compara
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Localization of alpha 1,3-fucosyltransferase VI in Weibel-Palade bodies of human endothelial cells.
Crystal structure of lactose synthase reveals a large conformational change in its catalytic component, the beta1,4-galactosyltransferase-I.
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Lactose synthase is a 1:1 complex of beta4Gal-T1 (catalytic) and alpha-lactalbumin (regulatory); alpha-lactalbumin promotes glucose binding and switches acceptor specificity from GlcNAc to glucose, enabling lactose synthesis.
"The lactose synthase (LS) enzyme is a 1:1 complex of a catalytic component, beta1,4-galactosyltransferse (beta4Gal-T1) and a regulatory component, alpha-lactalbumin (LA), a mammary gland-specific protein. LA promotes the binding of glucose (Glc) to beta4Gal-T1, thereby altering its sugar acceptor specificity from N-acetylglucosamine (GlcNAc) to glucose, which enables LS to synthesize lactose"
Oligosaccharide preferences of beta1,4-galactosyltransferase-I: crystal structures of Met340His mutant of human beta1,4-galactosyltransferase-I with a pentasaccharide and trisaccharides of the N-glycan moiety.
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Human beta4Gal-T1 transfers Gal from UDP-Gal to terminal GlcNAc of branched N-glycan chains, with preference for the 1,2-1,6-arm GlcNAc.
"beta-1,4-Galactosyltransferase-I (beta4Gal-T1) transfers galactose from UDP-galactose to N-acetylglucosamine (GlcNAc) residues of the branched N-linked oligosaccharide chains of glycoproteins"
Human colostrum: identification of minor proteins in the aqueous phase by proteomics.
Evidence for a molecular distinction between Golgi and cell surface forms of beta 1,4-galactosyltransferase.
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The longer isoform with a 13-aa N-terminal cytoplasmic extension is preferentially targeted to the plasma membrane; the shorter isoform resides in the Golgi.
"the longer GalTase protein, containing this unique 13-amino acid peptide, is preferentially targeted to the plasma membrane, and the shorter GalTase protein resides primarily within the Golgi compartment"
Large-scale proteomics and phosphoproteomics of urinary exosomes.
Proteomic analysis of human parotid gland exosomes by multidimensional protein identification technology (MudPIT).
Defining the membrane proteome of NK cells.
Analysis of the substrate binding sites of human galactosyltransferase by protein engineering.
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Mutagenesis of recombinant human galactosyltransferase identifies Tyr284, Tyr309 and Trp310 as critical for GlcNAc binding, and Tyr309 for UDP-galactose binding.
"Tyr284, Tyr309 and Trp310 are critically involved in the N-acetyglucosamine binding and Tyr309 is involved in UDP-galactose binding as well"
In-depth proteomic analyses of exosomes isolated from expressed prostatic secretions in urine.
Multi-level glyco-engineering techniques to generate IgG with defined Fc-glycans.
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B4GALT1 is used to galactosylate IgG Fc N-glycans; galactosylation level can be modulated by glyco-engineering, supporting the enzyme's role in complex N-glycan galactosylation.
"glycosyltransferases were transiently overexpressed to enhance bisection, galactosylation and sialylation"
Network inference from glycoproteomics data reveals new reactions in the IgG glycosylation pathway.
The charge heterogeneity of soluble human galactosyltransferases isolated from milk, amniotic fluid and malignant ascites.
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Soluble human UDP-galactose:GlcNAc galactosyltransferase purified from milk, amniotic fluid and ascites is active on free GlcNAc, glycoprotein acceptors and on glucose in the presence of alpha-lactalbumin.
"All enzyme forms showed similar activity when free N-acetylglucosamine, ovalbumin, sialic-acid-free ovine submaxillary mucin and glucose, in the presence of alpha-lactalbumin, were used as acceptor substrates"
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The enzyme exists as a soluble shed form in body fluids.
"UDP-galactose: N-acetylglucosamine galactosyltransferase was isolated from pooled human milk, pooled amniotic fluid and from two different individual samples of malignant ascites"
Genetic and functional evidence links a missense variant in B4GALT1 to lower LDL and fibrinogen.
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The hypomorphic p.Asn352Ser allele halves galactosyltransferase activity and lowers serum LDL-C and fibrinogen by reducing galactosylation/sialylation of ApoB100, fibrinogen, IgG and transferrin.
"The mutant protein had 50% lower galactosyltransferase activity compared with the wild-type protein. N-linked glycan profiling of human serum found serine 352 allele to be associated with decreased galactosylation and sialylation of apolipoprotein B100, fibrinogen, immunoglobulin G, and transferrin"
Divergent Enzymatic Assembly of a Comprehensive 64-Membered IgG N-Glycan Library for Functional Glycomics.
Immobilized enzyme cascade for targeted glycosylation.
Immunocytochemical demonstration of ecto-galactosyltransferase in absorptive intestinal cells.
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Ecto-galactosyltransferase is present on the plasma membrane of human duodenal enterocytes, most intensely on the brush border, oriented to the outer surface, with a possible adhesion role basolaterally.
"Antigenic sites detected with affinity-purified, monospecific antibodies were found at the plasma membrane of absorptive enterocytes with the most intense labeling appearing along the brush border membrane"
Immunocytochemical localization of galactosyltransferase in HeLa cells: codistribution with thiamine pyrophosphatase in trans-Golgi cisternae.
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Galactosyltransferase is localized to two-to-three trans cisternae of the Golgi, codistributing with thiamine pyrophosphatase.
"Label by gold particles was limited to two to three trans cisternae of the Golgi apparatus"
Analysis of the sequences of human beta-1,4-galactosyltransferase cDNA clones.
Golgi retention mechanism of beta-1,4-galactosyltransferase. Membrane-spanning domain-dependent homodimerization and association with alpha- and beta-tubulins.
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B4GALT1 forms transmembrane-domain-dependent homodimers/oligomers and associates with alpha- and beta-tubulin, mechanisms underlying its Golgi retention.
"beta-1,4-galactosyltransferase (GT) forms homodimers and large oligomers in vivo"
FutureHouse Falcon deep-research report for B4GALT1
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Deep-research synthesis: core function is Golgi (trans-Golgi) beta-1,4-galactosylation of terminal GlcNAc to form LacNAc on N-glycans/glycolipids, with Mn2+ cofactor and UDP-Gal donor; lactose synthase (with LALBA) is a tissue-specific core function; reported cancer/apoptosis/inflammation roles are pleiotropic, context-specific consequences of altered glycosylation and not dedicated B4GALT1 processes.
"The reviewed literature supports protein N-glycosylation and galactosylation as core constitutive functions, while roles in cancer cell migration, apoptosis, and inflammatory signaling represent context-specific, pleiotropic consequences"
Association of ADAM and B4GALT1 With ZP3
B4GALTs transfer Gal to the N-glycan precursor
B4GALTs transfer Gal to the keratan chain
B4GALTs transfer Gal to a branch of keratan
Defective B4GALT1 does not transfer Gal to the keratan chain
Defective B4GALT1 does not add Gal to N-glycan
B4GALT1:LALBA transfers Gal from UDP-Gal to Glc to form Lac
Exocytosis of azurophil granule membrane proteins
Exocytosis of secretory granule membrane proteins
Defective B4GALT1 does not transfer Gal to the N-glycan precursor
Defective B4GALT1 does not transfer Gal to a branch of keratan
Addition of galactose by beta 4-galactosyltransferases