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A0A4Z3 (A3LT2_RAT) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 54. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Alpha-1,3-galactosyltransferase 2

Short name=A3galt2
EC=2.4.1.87
Alternative name(s):
Isoglobotriaosylceramide synthase
Short name=iGb3 synthase
Short name=iGb3S
Gene names
Name:A3galt2
OrganismRattus norvegicus (Rat) [Reference proteome]
Taxonomic identifier10116 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeRattus

Protein attributes

Sequence length339 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Synthesizes the galactose-alpha(1,3)-galactose group on the glycosphingolipid isoglobotrihexosylceramide or isogloboside 3 (iGb3) by catalyzing the transfer of galactose from UDP-Galactose to its acceptor molecule Gal-beta-1,4-Glc-ceramide. Can also catalyze the addition of galactose to iGb3 itself to form polygalactose structures. Synthesis of iGb3 is the initial step in the formation of the isoglobo-series glycolipid pathway and is the precursor to isogloboside 4 (iGb4) and isoForssman glycolipids. Can glycosylate only lipids and not proteins and is solely responsible for initiating the synthesis of isoglobo-series glycosphingolipids.

Catalytic activity

UDP-alpha-D-galactose + beta-D-galactosyl-(1->4)-beta-N-acetyl-D-glucosaminyl-R = UDP + alpha-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-N-acetylglucosaminyl-R.

Cofactor

Manganese By similarity.

Subcellular location

Golgi apparatusGolgi stack membrane; Single-pass type II membrane protein. Note: Also found in numerous large vesicles throughout the cytoplasm of the soma.

Tissue specificity

Dorsal root ganglia neurons (at protein level). High levels in spleen, thymus and skeletal muscle, intermediate levels in lung, uterus, pituitary and heart, low levels in brain, and undetected in adrenal gland and liver.

Domain

The conserved DXD motif is involved in cofactor binding. The manganese ion interacts with the beta-phosphate group of UDP and may also have a role in catalysis.

Miscellaneous

This gene is not expressed in humans, and even if it were to be expressed, this enzyme appears to be inactive because of multiple mutations including an amino-acid substitution Leu-187 to Pro and Tyr-252 to Asn.

Sequence similarities

Belongs to the glycosyltransferase 6 family.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 339339Alpha-1,3-galactosyltransferase 2
PRO_0000314872

Regions

Topological domain1 – 1111Cytoplasmic Potential
Transmembrane12 – 3120Helical; Signal-anchor for type II membrane protein; Potential
Topological domain32 – 339308Lumenal Potential

Sites

Metal binding1981Manganese By similarity
Metal binding2001Manganese By similarity

Amino acid modifications

Glycosylation571N-linked (GlcNAc...) Potential
Glycosylation991N-linked (GlcNAc...) Potential

Experimental info

Mutagenesis1871L → P: Significant loss of activity.
Mutagenesis198 – 2003DVD → AVA: Catalytically inactive. Ref.1
Mutagenesis2521Y → N: Complete loss of activity.

Sequences

Sequence LengthMass (Da)Tools
A0A4Z3 [UniParc].

Last modified November 28, 2006. Version 1.
Checksum: 171A191001F0C6CF

FASTA33939,548
        10         20         30         40         50         60 
MALEGLRAKK RLLWRLFLSA FGLLGLYHYW FKIFRLFEVF IPMGICPMAI MPLLKDNFTG 

        70         80         90        100        110        120 
VLRHWARPEV LTCTSWGAPI IWDETFDPHV AEREARRQNL TIGLTVFAVG RYLEKYLEHF 

       130        140        150        160        170        180 
LVSAEQYFMV GQNVVYYVFT DRPEAVPHVA LGQGRLLRVK PVRREKRWQD VSMARMLTLH 

       190        200        210        220        230        240 
EALGGQLGRE ADYVFCLDVD QYFSGNFGPE VLADLVAQLH AWHFRWPRWM LPYERDKRSA 

       250        260        270        280        290        300 
AALSLSEGDF YYHAAVFGGS VAALLKLTAH CATGQQLDRE HGIEARWHDE SHLNKFFWLS 

       310        320        330 
KPTKLLSPEF CWAEEIGWRP EIHHPRLIWA PKEYALVRT 

« Hide

References

« Hide 'large scale' references
[1]"Expression cloning of a new member of the ABO blood group glycosyltransferases, iGb3 synthase, that directs the synthesis of isoglobo-glycosphingolipids."
Keusch J.J., Manzella S.M., Nyame K.A., Cummings R.D., Baenziger J.U.
J. Biol. Chem. 275:25308-25314(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, TISSUE SPECIFICITY, MUTAGENESIS OF 198-ASP--ASP-200.
Strain: Sprague-Dawley.
Tissue: Placenta.
[2]"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: Prostate.
[3]"Characterization of the rat alpha(1,3)galactosyltransferase: evidence for two independent genes encoding glycosyltransferases that synthesize Galalpha(1,3)Gal by two separate glycosylation pathways."
Taylor S.G., McKenzie I.F., Sandrin M.S.
Glycobiology 13:327-337(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, TISSUE SPECIFICITY.
[4]"Enzymes that synthesize the IB4 epitope are not sufficient to impart IB4 binding in dorsal root ganglia of rat."
Fullmer J.M., Riedl M., Williams F.G., Sandrin M., Elde R.
J. Comp. Neurol. 501:70-82(2007) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
[5]"Humans lack iGb3 due to the absence of functional iGb3-synthase: implications for NKT cell development and transplantation."
Christiansen D., Milland J., Mouhtouris E., Vaughan H., Pellicci D.G., McConville M.J., Godfrey D.I., Sandrin M.S.
PLoS Biol. 6:E172-E172(2008) [PubMed] [Europe PMC] [Abstract]
Cited for: SUBCELLULAR LOCATION, MUTAGENESIS OF LEU-187 AND TYR-252.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF248543 mRNA. Translation: AAF82757.1.
BC061714 mRNA. Translation: AAH61714.1.
RefSeqNP_612533.1. NM_138524.2.
UniGeneRn.37737.

3D structure databases

ProteinModelPortalA0A4Z3.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING10116.ENSRNOP00000007851.

Protein family/group databases

CAZyGT6. Glycosyltransferase Family 6.

Proteomic databases

PaxDbA0A4Z3.
PRIDEA0A4Z3.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENSRNOT00000007851; ENSRNOP00000007851; ENSRNOG00000005935.
GeneID171553.
KEGGrno:171553.

Organism-specific databases

CTD127550.
RGD727913. A3galt2.

Phylogenomic databases

eggNOGNOG277430.
GeneTreeENSGT00400000022032.
HOGENOMHOG000234339.
HOVERGENHBG003563.
InParanoidA0A4Z3.
OMAVFTERPA.
OrthoDBEOG7QG44N.
PhylomeDBA0A4Z3.
TreeFamTF330991.

Gene expression databases

GenevestigatorA0A4Z3.

Family and domain databases

InterProIPR005076. Glyco_trans_6.
[Graphical view]
PANTHERPTHR10462. PTHR10462. 1 hit.
PfamPF03414. Glyco_transf_6. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

NextBio622541.

Entry information

Entry nameA3LT2_RAT
AccessionPrimary (citable) accession number: A0A4Z3
Secondary accession number(s): A2JQW1
Entry history
Integrated into UniProtKB/Swiss-Prot: January 15, 2008
Last sequence update: November 28, 2006
Last modified: April 16, 2014
This is version 54 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families