Q9BUR5 (APOO_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Apolipoprotein O

Alternative name(s):
Protein FAM121B

Gene names

Name:	APOO
Synonyms:	FAM121B
ORF Names:	My025, UNQ1866/PRO4302

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	198 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	Promotes cholesterol efflux from macrophage cells. Detected in HDL, LDL and VLDL. Secreted by a microsomal triglyceride transfer protein (MTTP)-dependent mechanism, probably as a VLDL-associated protein that is subsequently transferred to HDL. May be involved in myocardium-protective mechanisms against lipid accumulation. Ref.6
Subcellular location	Membrane; Single-pass membrane protein Potential. Secreted Ref.6.
Tissue specificity	Expressed in all tissues examined. Up-regulated in diabetic heart. Ref.6
Post-translational modification	O-glycosylation; glycosaminoglycan of chondroitin-sulfate type.
Sequence similarities	Belongs to the apolipoprotein O family.

Ontologies

Keywords
Biological process	Lipid transport Transport
Cellular component	HDL LDL Membrane Secreted VLDL
Coding sequence diversity	Alternative splicing
Domain	Signal Transmembrane Transmembrane helix
PTM	Glycoprotein Proteoglycan
Technical term	Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	lipid transport Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	extracellular space Inferred from sequence or structural similarity PubMed 22261194. Source: BHF-UCL high-density lipoprotein particle Inferred from electronic annotation. Source: UniProtKB-KW integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW low-density lipoprotein particle Inferred from electronic annotation. Source: UniProtKB-KW very-low-density lipoprotein particle Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Alternative products

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

Isoform 1 (identifier: Q9BUR5-1)

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: Q9BUR5-2)

The sequence of this isoform differs from the canonical sequence as follows:
     80-109: ETYSQTKPKMQSLVQWGLDSYDYLQNAPPG → TAMTISKMHLLD

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 25	25	Potential
	Chain	26 – 198	173	Apolipoprotein O		PRO_0000254646
Regions
	Transmembrane	108 – 128	21	Helical; Potential
Amino acid modifications
	Glycosylation	162	1	O-linked (Xyl...) (chondroitin sulfate) Potential
Natural variations
	Alternative sequence	80 – 109	30	ETYSQ…NAPPG → TAMTISKMHLLD in isoform 2.		VSP_023333

Sequences

	Sequence		Length	Mass (Da)
	Isoform 1 [UniParc]. Last modified June 1, 2001. Version 1. Checksum: BEC99607F54E98E2	FASTA	198	22,285
	10 20 30 40 50 60 MFKVIQRSVG PASLSLLTFK VYAAPKKDSP PKNSVKVDEL SLYSVPEGQS KYVEEARSQL 70 80 90 100 110 120 EESISQLRHY CEPYTTWCQE TYSQTKPKMQ SLVQWGLDSY DYLQNAPPGF FPRLGVIGFA 130 140 150 160 170 180 GLIGLLLARG SKIKKLVYPP GFMGLAASLY YPQQAIVFAQ VSGERLYDWG LRGYIVIEDL 190 WKENFQKPGN VKNSPGTK
	Isoform 2 [UniParc]. Checksum: 0612F903AB6390E1	FASTA	180	20,199
	10 20 30 40 50 60 MFKVIQRSVG PASLSLLTFK VYAAPKKDSP PKNSVKVDEL SLYSVPEGQS KYVEEARSQL 70 80 90 100 110 120 EESISQLRHY CEPYTTWCQT AMTISKMHLL DFFPRLGVIG FAGLIGLLLA RGSKIKKLVY 130 140 150 160 170 180 PPGFMGLAAS LYYPQQAIVF AQVSGERLYD WGLRGYIVIE DLWKENFQKP GNVKNSPGTK

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	Mao Y.M., Xie Y., Zheng Z.H. Submitted (APR-1998) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2). Tissue: Fetal brain.
[2]	"The secreted protein discovery initiative (SPDI), a large-scale effort to identify novel human secreted and transmembrane proteins: a bioinformatics assessment." Clark H.F., Gurney A.L., Abaya E., Baker K., Baldwin D.T., Brush J., Chen J., Chow B., Chui C., Crowley C., Currell B., Deuel B., Dowd P., Eaton D., Foster J.S., Grimaldi C., Gu Q., Hass P.E. , Heldens S., Huang A., Kim H.S., Klimowski L., Jin Y., Johnson S., Lee J., Lewis L., Liao D., Mark M.R., Robbie E., Sanchez C., Schoenfeld J., Seshagiri S., Simmons L., Singh J., Smith V., Stinson J., Vagts A., Vandlen R.L., Watanabe C., Wieand D., Woods K., Xie M.-H., Yansura D.G., Yi S., Yu G., Yuan J., Zhang M., Zhang Z., Goddard A.D., Wood W.I., Godowski P.J., Gray A.M. Genome Res. 13:2265-2270(2003) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
[3]	"Complete sequencing and characterization of 21,243 full-length human cDNAs." Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S. , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S. Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). Tissue: Brain.
[4]	Mural R.J., Istrail S., Sutton G.G., Florea L., Halpern A.L., Mobarry C.M., Lippert R., Walenz B., Shatkay H., Dew I., Miller J.R., Flanigan M.J., Edwards N.J., Bolanos R., Fasulo D., Halldorsson B.V., Hannenhalli S., Turner R. , Yooseph S., Lu F., Nusskern D.R., Shue B.C., Zheng X.H., Zhong F., Delcher A.L., Huson D.H., Kravitz S.A., Mouchard L., Reinert K., Remington K.A., Clark A.G., Waterman M.S., Eichler E.E., Adams M.D., Hunkapiller M.W., Myers E.W., Venter J.C. Submitted (JUL-2005) to the EMBL/GenBank/DDBJ databases 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] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1). Tissue: Lung, Skin and Urinary bladder.
[6]	"ApoO, a novel apolipoprotein, is an original glycoprotein up-regulated by diabetes in human heart." Lamant M., Smih F., Harmancey R., Philip-Couderc P., Pathak A., Roncalli J., Galinier M., Collet X., Massabuau P., Senard J.-M., Rouet P. J. Biol. Chem. 281:36289-36302(2006) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, COVALENT LINKAGE WITH CHONDROITIN SULFATE.
[7]	"Initial characterization of the human central proteome." Burkard T.R., Planyavsky M., Kaupe I., Breitwieser F.P., Buerckstuemmer T., Bennett K.L., Superti-Furga G., Colinge J. BMC Syst. Biol. 5:17-17(2011) [PubMed] [Europe PMC] [Abstract] Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AF061264 mRNA. Translation: AAG43139.1. AY359114 mRNA. Translation: AAQ89472.1. AK311865 mRNA. Translation: BAG34806.1. CH471074 Genomic DNA. Translation: EAW99002.1. BC002333 mRNA. Translation: AAH02333.1. BC010102 mRNA. Translation: AAH10102.1. BC016814 mRNA. Translation: AAH16814.1.
IPI	IPI00042580. IPI00797546.
RefSeq	NP_077027.1. NM_024122.4.
UniGene	Hs.495851.
3D structure databases
ProteinModelPortal	Q9BUR5.
ModBase	Search...
Protein-protein interaction databases
STRING	9606.ENSP00000368528.
PTM databases
PhosphoSite	Q9BUR5.
Polymorphism databases
DMDM	74733244.
Proteomic databases
PaxDb	Q9BUR5.
PeptideAtlas	Q9BUR5.
PRIDE	Q9BUR5.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
Ensembl	ENST00000379226; ENSP00000368528; ENSG00000184831.
GeneID	79135.
KEGG	hsa:79135.
UCSC	uc004dax.3. human.
Organism-specific databases
CTD	79135.
GeneCards	GC0XM023851.
HGNC	HGNC:28727. APOO.
HPA	HPA003187.
MIM	300753. gene.
neXtProt	NX_Q9BUR5.
PharmGKB	PA162376709.
GenAtlas	Search...
Phylogenomic databases
eggNOG	NOG250883.
HOGENOM	HOG000034011.
HOVERGEN	HBG059567.
InParanoid	Q9BUR5.
OMA	LRHHCEP.
OrthoDB	EOG479F84.
PhylomeDB	Q9BUR5.
Gene expression databases
ArrayExpress	Q9BUR5.
Bgee	Q9BUR5.
CleanEx	HS_APOO.
Genevestigator	Q9BUR5.
GermOnline	ENSG00000184831. Homo sapiens.
Family and domain databases
InterPro	IPR019166. Apolipoprotein_O. [Graphical view]
Pfam	PF09769. ApoO. 1 hit. [Graphical view]
ProtoNet	Search...
Other
GenomeRNAi	79135.
NextBio	68006.
SOURCE	Search...

Entry information

Entry name

APOO_HUMAN

Accession

Primary (citable) accession number: Q9BUR5
Secondary accession number(s): B2R4K9, Q9H3J9

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 31, 2006
Last sequence update:	June 1, 2001
Last modified:	April 3, 2013
This is version 79 of the entry and version 1 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.