Q6P9A2 (GLT18_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Polypeptide N-acetylgalactosaminyltransferase 18
EC=2.4.1.41

Alternative name(s):
Polypeptide GalNAc transferase-like protein 4
Short name=GalNAc-T-like protein 4
Short name=pp-GaNTase-like protein 4
Polypeptide N-acetylgalactosaminyltransferase-like protein 4
Protein-UDP acetylgalactosaminyltransferase-like protein 4
UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase-like protein 4

Gene names

Name:	GALNT18
Synonyms:	GALNTL4

Organism

Homo sapiens (Human) [Reference proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Primates › Haplorrhini › Simiiformes › Catarrhini › Hominoidea › Hominidae › Homininae › Homo

Protein attributes

Sequence length	607 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	May catalyze the initial reaction in O-linked oligosaccharide biosynthesis, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor By similarity.
Catalytic activity	UDP-N-acetyl-alpha-D-galactosamine + polypeptide = UDP + N-acetyl-alpha-D-galactosaminyl-polypeptide.
Cofactor	Manganese By similarity. Calcium By similarity.
Pathway	Protein modification; protein glycosylation.
Subcellular location	Golgi apparatus membrane; Single-pass type II membrane protein By similarity.
Domain	There are two conserved domains in the glycosyltransferase region: the N-terminal domain (domain A, also called GT1 motif), which is probably involved in manganese coordination and substrate binding and the C-terminal domain (domain B, also called Gal/GalNAc-T motif), which is probably involved in catalytic reaction and UDP-Gal binding By similarity. The ricin B-type lectin domain binds to GalNAc and contributes to the glycopeptide specificity By similarity.
Sequence similarities	Belongs to the glycosyltransferase 2 family. GalNAc-T subfamily. Contains 1 ricin B-type lectin domain.
Sequence caution	The sequence AAD20062.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.

Ontologies

Keywords
Cellular component	Golgi apparatus Membrane
Coding sequence diversity	Alternative splicing
Domain	Signal-anchor Transmembrane Transmembrane helix
Ligand	Calcium Lectin Manganese
Molecular function	Glycosyltransferase Transferase
PTM	Disulfide bond Glycoprotein
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	protein glycosylation Inferred from electronic annotation. Source: UniProtKB-UniPathway
Cellular_component	Golgi membrane Inferred from electronic annotation. Source: UniProtKB-SubCell integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular_function	polypeptide N-acetylgalactosaminyltransferase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Alternative products

This entry describes 2 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: Q6P9A2-1)

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

Isoform 2 (identifier: Q6P9A2-2)

The sequence of this isoform differs from the canonical sequence as follows:
     79-91: EAPAKPEEAEAEP → GYRRNFSLLNVSN
     92-607: Missing.

Note: No experimental confirmation available.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 607	607	Polypeptide N-acetylgalactosaminyltransferase 18		PRO_0000059141
Regions
	Topological domain	1 – 12	12	Cytoplasmic Potential
	Transmembrane	13 – 35	23	Helical; Signal-anchor for type II membrane protein; Potential
	Topological domain	36 – 607	572	Lumenal Potential
	Domain	469 – 599	131	Ricin B-type lectin
	Region	153 – 267	115	Catalytic subdomain A
	Region	324 – 385	62	Catalytic subdomain B
Amino acid modifications
	Glycosylation	146	1	N-linked (GlcNAc...) Potential
	Glycosylation	195	1	N-linked (GlcNAc...) Potential
	Glycosylation	320	1	N-linked (GlcNAc...) Potential
	Disulfide bond	482 ↔ 498		By similarity
	Disulfide bond	530 ↔ 543		By similarity
	Disulfide bond	571 ↔ 591		By similarity
Natural variations
	Alternative sequence	79 – 91	13	EAPAK…AEAEP → GYRRNFSLLNVSN in isoform 2.		VSP_011234
	Alternative sequence	92 – 607	516	Missing in isoform 2.		VSP_011235
Experimental info
	Sequence conflict	133	1	D → G in AAH60864. Ref.2
	Sequence conflict	541	1	I → T in AAH60864. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified October 17, 2006. Version 2. Checksum: 8FFA7BCB5016FF0C	FASTA	607	69,561
	10 20 30 40 50 60 MVCTRKTKTL VSTCVILSGM TNIICLLYVG WVTNYIASVY VRGQEPAPDK KLEEDKGDTL 70 80 90 100 110 120 KIIERLDHLE NVIKQHIQEA PAKPEEAEAE PFTDSSLFAH WGQELSPEGR RVALKQFQYY 130 140 150 160 170 180 GYNAYLSDRL PLDRPLPDLR PSGCRNLSFP DSLPEVSIVF IFVNEALSVL LRSIHSAMER 190 200 210 220 230 240 TPPHLLKEII LVDDNSSNEE LKEKLTEYVD KVNSQKPGFI KVVRHSKQEG LIRSRVSGWR 250 260 270 280 290 300 AATAPVVALF DAHVEFNVGW AEPVLTRIKE NRKRIISPSF DNIKYDNFEI EEYPLAAQGF 310 320 330 340 350 360 DWELWCRYLN PPKAWWKLEN STAPIRSPAL IGCFIVDRQY FQEIGLLDEG MEVYGGENVE 370 380 390 400 410 420 LGIRVWQCGG SVEVLPCSRI AHIERAHKPY TEDLTAHVRR NALRVAEVWM DEFKSHVYMA 430 440 450 460 470 480 WNIPQEDSGI DIGDITARKA LRKQLQCKTF RWYLVSVYPE MRMYSDIIAY GVLQNSLKTD 490 500 510 520 530 540 LCLDQGPDTE NVPIMYICHG MTPQNVYYTS SQQIHVGILS PTVDDDDNRC LVDVNSRPRL 550 560 570 580 590 600 IECSYAKAKR MKLHWQFSQG GPIQNRKSKR CLELQENSDL EFGFQLVLQK CSGQHWSITN VLRSLAS
	Isoform 2 [UniParc]. Checksum: 4EBD1A8E212F25C7	FASTA	91	10,397
	10 20 30 40 50 60 MVCTRKTKTL VSTCVILSGM TNIICLLYVG WVTNYIASVY VRGQEPAPDK KLEEDKGDTL 70 80 90 KIIERLDHLE NVIKQHIQGY RRNFSLLNVS N

References

[1]	Mei G., Yu W., Gibbs R.A. Submitted (FEB-1999) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2). Tissue: Brain.
[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] (ISOFORM 1). Tissue: Placenta.
+	Additional computationally mapped references.

Web resources

GGDB

GlycoGene database

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF131852 mRNA. Translation: AAD20062.1. Different initiation. BC060864 mRNA. Translation: AAH60864.1. BC037341 mRNA. Translation: AAH37341.3.
IPI	IPI00168626. IPI00454596.
RefSeq	NP_940918.2. NM_198516.2.
UniGene	Hs.655152.
3D structure databases
ProteinModelPortal	Q6P9A2.
ModBase	Search...
Protein-protein interaction databases
STRING	9606.ENSP00000227756.
Protein family/group databases
CAZy	CBM13. Carbohydrate-Binding Module Family 13. GT27. Glycosyltransferase Family 27.
PTM databases
PhosphoSite	Q6P9A2.
Polymorphism databases
DMDM	116242498.
Proteomic databases
PaxDb	Q6P9A2.
PRIDE	Q6P9A2.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENST00000227756; ENSP00000227756; ENSG00000110328.
GeneID	374378.
KEGG	hsa:374378.
UCSC	uc001mjo.2. human.
Organism-specific databases
CTD	374378.
GeneCards	GC11M011292.
HGNC	HGNC:30488. GALNT18.
HPA	HPA012955.
neXtProt	NX_Q6P9A2.
PharmGKB	PA134950929.
GenAtlas	Search...
Phylogenomic databases
eggNOG	NOG123124.
HOGENOM	HOG000038228.
HOVERGEN	HBG051699.
InParanoid	Q6P9A2.
KO	K00710.
OMA	APDKKLE.
OrthoDB	EOG4M91R2.
PhylomeDB	Q6P9A2.
Enzyme and pathway databases
Reactome	REACT_17015. Metabolism of proteins.
UniPathway	UPA00378.
Gene expression databases
ArrayExpress	Q6P9A2.
Bgee	Q6P9A2.
CleanEx	HS_GALNTL4.
Genevestigator	Q6P9A2.
GermOnline	ENSG00000110328. Homo sapiens.
Family and domain databases
InterPro	IPR001173. Glyco_trans_2. IPR000772. Ricin_B_lectin. [Graphical view]
Pfam	PF00535. Glycos_transf_2. 1 hit. PF00652. Ricin_B_lectin. 1 hit. [Graphical view]
SMART	SM00458. RICIN. 1 hit. [Graphical view]
SUPFAM	SSF50370. RicinB_like. 1 hit.
PROSITE	PS50231. RICIN_B_LECTIN. 1 hit. [Graphical view]
ProtoNet	Search...
Other
ChiTaRS	GALNTL4. human.
GenomeRNAi	374378.
NextBio	100162.

Entry information

Entry name

GLT18_HUMAN

Accession

Primary (citable) accession number: Q6P9A2
Secondary accession number(s): O95903, Q8NDY9

Entry history

Integrated into UniProtKB/Swiss-Prot:	August 16, 2004
Last sequence update:	October 17, 2006
Last modified:	May 1, 2013
This is version 91 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.