Reviewed, UniProtKB/Swiss-Prot Q9BRB3 (PIGQ_HUMAN)

Names and origin

Protein names

Recommended name:
    Phosphatidylinositol N-acetylglucosaminyltransferase subunit Q
    EC=2.4.1.198
Alternative name(s):
    Phosphatidylinositol-glycan biosynthesis class Q protein
      Short name=PIG-Q
    N-acetylglucosamyl transferase component GPI1

Gene names

Name:	PIGQ
Synonyms:	GPI1

Organism

Homo sapiens (Human)

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	760 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Part of the complex catalyzing the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to phosphatidylinositol, the first step of GPI biosynthesis.
Catalytic activity	UDP-N-acetyl-D-glucosamine + 1-phosphatidyl-1D-myo-inositol = UDP + 6-(N-acetyl-alpha-D-glucosaminyl)-1-phosphatidyl-1D-myo-inositol.
Pathway	Glycolipid biosynthesis; glycosylphosphatidylinositol-anchor biosynthesis.
Subunit structure	Associates with PIGA, PIGC, PIGH, PIGP and DPM2. The latter is not essential for activity.
Subcellular location	Membrane; Multi-pass membrane protein Potential.
Sequence similarities	Belongs to the PIGQ family.

Ontologies

Keywords
Biological process	GPI-anchor biosynthesis
Cellular component	Membrane
Coding sequence diversity	Alternative splicing Polymorphism
Domain	Transmembrane
Molecular function	Glycosyltransferase Transferase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	carbohydrate metabolic process Ref.1 Traceable author statement. Source: ProtInc preassembly of GPI anchor in ER membrane Inferred from Experiment. Source: Reactome
Cellular component	integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	phosphatidylinositol N-acetylglucosaminyltransferase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Alternative products

This entry describes 3 isoforms produced by alternative splicing. [Align] [Select]

Isoform 1 (identifier: Q9BRB3-1)

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.

Note: No experimental confirmation available.

Isoform 2 (identifier: Q9BRB3-2)

The sequence of this isoform differs from the canonical sequence as follows:
     511-581: DKPTALQPRG...HGHSQPSALP → AGVKFRVLRH...PWRQRGDKQD
     582-760: Missing.

Isoform 3 (identifier: Q9BRB3-3)

The sequence of this isoform differs from the canonical sequence as follows:
     275-299: KANTVASVLLDVALGLMLLSWLHGR → CGPALVSAGLGACPLAPSPSPSAPR
     300-760: Missing.

Note: No experimental confirmation available.

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.6
	Chain	2 – 760	759	Phosphatidylinositol N-acetylglucosaminyltransferase subunit Q		PRO_0000215664
Regions
	Transmembrane	278 – 298	21	Potential
	Transmembrane	349 – 371	23	Potential
	Transmembrane	378 – 400	23	Potential
	Transmembrane	446 – 468	23	Potential
	Transmembrane	475 – 497	23	Potential
	Compositional bias	214 – 536	323	Leu-rich
Natural variations
	Alternative sequence	275 – 299	25	KANTV…WLHGR → CGPALVSAGLGACPLAPSPS PSAPR in isoform 3.		VSP_007279
	Alternative sequence	300 – 760	461	Missing in isoform 3.		VSP_007280
	Alternative sequence	511 – 581	71	DKPTA…PSALP → AGVKFRVLRHEAGRPLRLLM QINPLPYSRVVHTYRLPSCG CHPKHSWGALCRKLFLGELI YPWRQRGDKQD in isoform 2.		VSP_007281
	Alternative sequence	582 – 760	179	Missing in isoform 2.		VSP_007282
	Natural variant	14	1	T → A: dbSNP rs2071979. Ref.3 Ref.5		VAR_015596
	Natural variant	592	1	C → R: dbSNP rs1045277.		VAR_053579
	Natural variant	668	1	C → R: dbSNP rs710924.		VAR_053580
	Natural variant	668	1	C → Y: dbSNP rs710925.		VAR_053581

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: DBF900ADCE08DA98	FASTA	760	84,082
	10 20 30 40 50 60 MVLKAFFPTC CVSTDSGLLV GRWVPEQSSA VVLAVLHFPF IPIQVKQLLA QVRQASQVGV 70 80 90 100 110 120 AVLGTWCHCR QEPEESLGRF LESLGAVFPH EPWLRLCRER GGTFWSCEAT HRQAPTAPGA 130 140 150 160 170 180 PGEDQVMLIF YDQRQVLLSQ LHLPTVLPDR QAGATTASTG GLAAVFDTVA RSEVLFRSDR 190 200 210 220 230 240 FDEGPVRLSH WQSEGVEASI LAELARRASG PICLLLASLL SLVSAVSACR VFKLWPLSFL 250 260 270 280 290 300 GSKLSTCEQL RHRLEHLTLI FSTRKAENPA QLMRKANTVA SVLLDVALGL MLLSWLHGRS 310 320 330 340 350 360 RIGHLADALV PVADHVAEEL QHLLQWLMGA PAGLKMNRAL DQVLGRFFLY HIHLWISYIH 370 380 390 400 410 420 LMSPFVEHIL WHVGLSACLG LTVALSLLSD IIALLTFHIY CFYVYGARLY CLKIHGLSSL 430 440 450 460 470 480 WRLFRGKKWN VLRQRVDSCS YDLDQLFIGT LLFTILLFLL PTTALYYLVF TLLRLLVVAV 490 500 510 520 530 540 QGLIHLLVDL INSLPLYSLG LRLCRPYRLA DKPTALQPRG AHLPPPQLWL PPQALLGRPV 550 560 570 580 590 600 PQAVPWGAHL PLEAERGQAG LRELLARLAP PHGHSQPSAL PGWHQLSWRM SCALWTLLCA 610 620 630 640 650 660 PEHGRPCYHT LGLEVIGSEQ MWGWPARLAA LHHWHCLPWD PLPTCCGHHG GEHSNPRCPE 670 680 690 700 710 720 HCPMPTLCTQ VQRVRPPQQP QVEGWSPWGL PSGSALAVGV EGPCQDEPPS PRHPLAPSAE 730 740 750 760 QHPASGGLKQ SLTPVPSGPG PSLPEPHGVY LRMFPGEVAL
	Isoform 2. Checksum: A5C055C7C144661D	FASTA	581	65,344
	10 20 30 40 50 60 MVLKAFFPTC CVSTDSGLLV GRWVPEQSSA VVLAVLHFPF IPIQVKQLLA QVRQASQVGV 70 80 90 100 110 120 AVLGTWCHCR QEPEESLGRF LESLGAVFPH EPWLRLCRER GGTFWSCEAT HRQAPTAPGA 130 140 150 160 170 180 PGEDQVMLIF YDQRQVLLSQ LHLPTVLPDR QAGATTASTG GLAAVFDTVA RSEVLFRSDR 190 200 210 220 230 240 FDEGPVRLSH WQSEGVEASI LAELARRASG PICLLLASLL SLVSAVSACR VFKLWPLSFL 250 260 270 280 290 300 GSKLSTCEQL RHRLEHLTLI FSTRKAENPA QLMRKANTVA SVLLDVALGL MLLSWLHGRS 310 320 330 340 350 360 RIGHLADALV PVADHVAEEL QHLLQWLMGA PAGLKMNRAL DQVLGRFFLY HIHLWISYIH 370 380 390 400 410 420 LMSPFVEHIL WHVGLSACLG LTVALSLLSD IIALLTFHIY CFYVYGARLY CLKIHGLSSL 430 440 450 460 470 480 WRLFRGKKWN VLRQRVDSCS YDLDQLFIGT LLFTILLFLL PTTALYYLVF TLLRLLVVAV 490 500 510 520 530 540 QGLIHLLVDL INSLPLYSLG LRLCRPYRLA AGVKFRVLRH EAGRPLRLLM QINPLPYSRV 550 560 570 580 VHTYRLPSCG CHPKHSWGAL CRKLFLGELI YPWRQRGDKQ D
	Isoform 3. Checksum: 260AA154769F6F41	FASTA	299	32,471
	10 20 30 40 50 60 MVLKAFFPTC CVSTDSGLLV GRWVPEQSSA VVLAVLHFPF IPIQVKQLLA QVRQASQVGV 70 80 90 100 110 120 AVLGTWCHCR QEPEESLGRF LESLGAVFPH EPWLRLCRER GGTFWSCEAT HRQAPTAPGA 130 140 150 160 170 180 PGEDQVMLIF YDQRQVLLSQ LHLPTVLPDR QAGATTASTG GLAAVFDTVA RSEVLFRSDR 190 200 210 220 230 240 FDEGPVRLSH WQSEGVEASI LAELARRASG PICLLLASLL SLVSAVSACR VFKLWPLSFL 250 260 270 280 290 GSKLSTCEQL RHRLEHLTLI FSTRKAENPA QLMRCGPALV SAGLGACPLA PSPSPSAPR

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Human and mouse Gpi1p homologues restore glycosylphosphatidylinositol membrane anchor biosynthesis in yeast mutants." Tiede A., Schubert J., Nischan C., Jensen I., Westfall B., Taron C.H., Orlean P., Schmidt R.E. Biochem. J. 334:609-616(1998) [PubMed: 9729469] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
[2]	"The first step of glycosylphosphatidylinositol biosynthesis is mediated by a complex of PIG-A, PIG-H, PIG-C and GPI1." Watanabe R., Inoue N., Westfall B., Taron C.H., Orlean P., Takeda J., Kinoshita T. EMBO J. 17:877-885(1998) [PubMed: 9463366] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2).
[3]	"Sequence, structure and pathology of the fully annotated terminal 2 Mb of the short arm of human chromosome 16." Daniels R.J., Peden J.F., Lloyd C., Horsley S.W., Clark K., Tufarelli C., Kearney L., Buckle V.J., Doggett N.A., Flint J., Higgs D.R. Hum. Mol. Genet. 10:339-352(2001) [PubMed: 11157797] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA], VARIANT ALA-14.
[4]	"The sequence and analysis of duplication-rich human chromosome 16." Martin J., Han C., Gordon L.A., Terry A., Prabhakar S., She X., Xie G., Hellsten U., Chan Y.M., Altherr M., Couronne O., Aerts A., Bajorek E., Black S., Blumer H., Branscomb E., Brown N.C., Bruno W.J. , Buckingham J.M., Callen D.F., Campbell C.S., Campbell M.L., Campbell E.W., Caoile C., Challacombe J.F., Chasteen L.A., Chertkov O., Chi H.C., Christensen M., Clark L.M., Cohn J.D., Denys M., Detter J.C., Dickson M., Dimitrijevic-Bussod M., Escobar J., Fawcett J.J., Flowers D., Fotopulos D., Glavina T., Gomez M., Gonzales E., Goodstein D., Goodwin L.A., Grady D.L., Grigoriev I., Groza M., Hammon N., Hawkins T., Haydu L., Hildebrand C.E., Huang W., Israni S., Jett J., Jewett P.B., Kadner K., Kimball H., Kobayashi A., Krawczyk M.-C., Leyba T., Longmire J.L., Lopez F., Lou Y., Lowry S., Ludeman T., Manohar C.F., Mark G.A., McMurray K.L., Meincke L.J., Morgan J., Moyzis R.K., Mundt M.O., Munk A.C., Nandkeshwar R.D., Pitluck S., Pollard M., Predki P., Parson-Quintana B., Ramirez L., Rash S., Retterer J., Ricke D.O., Robinson D.L., Rodriguez A., Salamov A., Saunders E.H., Scott D., Shough T., Stallings R.L., Stalvey M., Sutherland R.D., Tapia R., Tesmer J.G., Thayer N., Thompson L.S., Tice H., Torney D.C., Tran-Gyamfi M., Tsai M., Ulanovsky L.E., Ustaszewska A., Vo N., White P.S., Williams A.L., Wills P.L., Wu J.-R., Wu K., Yang J., DeJong P., Bruce D., Doggett N.A., Deaven L., Schmutz J., Grimwood J., Richardson P., Rokhsar D.S., Eichler E.E., Gilna P., Lucas S.M., Myers R.M., Rubin E.M., Pennacchio L.A. Nature 432:988-994(2004) [PubMed: 15616553] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[5]	"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: 15489334] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORMS 1 AND 3), VARIANT ALA-14. Tissue: Melanoma and Retinoblastoma.
[6]	"Initial enzyme for glycosylphosphatidylinositol biosynthesis requires PIG-P and is regulated by DPM2." Watanabe R., Murakami Y., Marmor M.D., Inoue N., Maeda Y., Hino J., Kangawa K., Julius M., Kinoshita T. EMBO J. 19:4402-4411(2000) [PubMed: 10944123] [Abstract] Cited for: PROTEIN SEQUENCE OF 2-6.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AF030177 mRNA. Translation: AAC32661.1. AB003723 mRNA. Translation: BAA24948.1. AE006464 Genomic DNA. Translation: AAK61235.1. Z98883 Genomic DNA. Translation: CAB56148.2. Z98883 Genomic DNA. Translation: CAM26442.1. BC006377 mRNA. Translation: AAH06377.1. BC010094 mRNA. No translation available.
IPI	IPI00009447. IPI00062113. IPI00163323.
RefSeq	NP_004195.2. NP_683721.1.
UniGene	Hs.709562
3D structure databases
ModBase	Search...
Proteomic databases
PRIDE	Q9BRB3.
Genome annotation databases
Ensembl	ENSG00000007541. Homo sapiens. [Contig view]
GeneID	9091.
KEGG	hsa:9091.
Organism-specific databases
GeneCards	GC16P000560.
H-InvDB	HIX0012652.
HGNC	HGNC:14135. PIGQ.
MIM	605754. gene.
PharmGKB	PA33299.
GenAtlas	Search...
Phylogenomic databases
HOGENOM	Q9BRB3.
HOVERGEN	Q9BRB3.
OMA	Q9BRB3. LVPVADH.
Enzyme and pathway databases
BRENDA	2.4.1.198. 247.
Reactome	REACT_1069. Post-translational protein modification.
Gene expression databases
ArrayExpress	Q9BRB3.
Bgee	Q9BRB3.
CleanEx	HS_PIGQ.
GermOnline	ENSG00000007541. Homo sapiens.
Family and domain databases
InterPro	IPR007720. GlcNAc_Gpi1. [Graphical view]
Pfam	PF05024. Gpi1. 1 hit. [Graphical view]
ProtoNet	Search...
Other Resources
NextBio	34061.
SOURCE	Search...

Entry information

Entry name

PIGQ_HUMAN

Accession

Primary (citable) accession number: Q9BRB3
Secondary accession number(s): A2IDE1 , O14927, Q96G00, Q96S22, Q9UJH4

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 23, 2003
Last sequence update:	January 23, 2007
Last modified:	June 16, 2009
This is version 67 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)