SAR1B (secretion associated Ras related GTPase 1B)

Gene

• Entrez ID: 51128
• Gene name: Secretion associated Ras related GTPase 1B
• Gene symbol: SAR1B
• Synonyms: ANDD, CMRD, GTBPB, SARA2
• Chromosome: 5
• Chromosome location: 5q31.1
• Summary: The protein encoded by this gene is a small GTPase that acts as a homodimer. The encoded protein is activated by the guanine nucleotide exchange factor PREB and is involved in protein transport from the endoplasmic reticulum to the Golgi. This protein is part of the COPII coat complex. Defects in this gene are a cause of chylomicron retention disease (CMRD), also known as Anderson disease (ANDD). Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Mar 2010]

SNPs

SNP ID	Visualize variation	Clinical significance	Consequence
rs28942109	C>T	Pathogenic, likely-pathogenic	Coding sequence variant, missense variant
rs28942110	A>T	Pathogenic	Coding sequence variant, missense variant
rs121917846	C>T	Pathogenic	Coding sequence variant, missense variant
rs137853125	C>A	Pathogenic	Stop gained, coding sequence variant
rs137853126	C>A	Pathogenic	Coding sequence variant, missense variant
rs1580645070	->GTAA	Pathogenic	Frameshift variant, coding sequence variant
rs1580645999	C>G	Pathogenic	Splice acceptor variant
rs1580648526	->ATGG	Pathogenic	Frameshift variant, coding sequence variant
rs1580653772	CA>-	Pathogenic	Frameshift variant, coding sequence variant

miRNA

miRTarBase ID	miRNA	Experiments	Reference
MIRT038111	hsa-miR-423-5p	CLASH	23622248
MIRT048276	hsa-miR-196a-5p	CLASH	23622248
MIRT048276	hsa-miR-196a-5p	PAR-CLIP	22012620
MIRT095081	hsa-miR-3529-3p	PAR-CLIP	22012620
MIRT095083	hsa-miR-7844-5p	PAR-CLIP	22012620
MIRT214454	hsa-miR-1277-5p	PAR-CLIP	22012620
MIRT256436	hsa-miR-34b-3p	HITS-CLIP	22927820
MIRT439708	hsa-miR-154-5p	HITS-CLIP	24374217
MIRT439709	hsa-miR-382-5p	HITS-CLIP	24374217
MIRT468797	hsa-miR-7150	PAR-CLIP	23592263
MIRT468798	hsa-miR-4736	PAR-CLIP	23592263
MIRT468799	hsa-miR-4763-3p	PAR-CLIP	23592263
MIRT468800	hsa-miR-1207-5p	PAR-CLIP	23592263
MIRT468801	hsa-miR-3665	PAR-CLIP	23592263
MIRT468802	hsa-miR-125a-3p	PAR-CLIP	23592263
MIRT468803	hsa-miR-4773	PAR-CLIP	23592263
MIRT468804	hsa-miR-4803	PAR-CLIP	23592263
MIRT534472	hsa-miR-4671-3p	PAR-CLIP	22012620
MIRT534473	hsa-miR-4473	PAR-CLIP	22012620
MIRT534474	hsa-miR-656-3p	PAR-CLIP	22012620
MIRT534475	hsa-miR-519e-3p	PAR-CLIP	22012620
MIRT534476	hsa-miR-515-3p	PAR-CLIP	22012620
MIRT534477	hsa-miR-33b-3p	PAR-CLIP	22012620
MIRT534478	hsa-miR-371a-3p	PAR-CLIP	22012620
MIRT534479	hsa-miR-371b-3p	PAR-CLIP	22012620
MIRT534480	hsa-miR-3180-5p	PAR-CLIP	22012620
MIRT534481	hsa-miR-302c-5p	PAR-CLIP	22012620
MIRT534482	hsa-miR-525-5p	PAR-CLIP	22012620
MIRT534483	hsa-miR-520a-5p	PAR-CLIP	22012620
MIRT534484	hsa-miR-3143	PAR-CLIP	22012620
MIRT534485	hsa-miR-27b-5p	PAR-CLIP	22012620
MIRT534486	hsa-miR-1272	PAR-CLIP	22012620
MIRT534487	hsa-miR-556-5p	PAR-CLIP	22012620
MIRT534488	hsa-miR-208b-5p	PAR-CLIP	22012620
MIRT534489	hsa-miR-208a-5p	PAR-CLIP	22012620
MIRT534490	hsa-miR-8054	PAR-CLIP	22012620
MIRT534491	hsa-miR-548k	PAR-CLIP	22012620
MIRT534492	hsa-miR-548av-5p	PAR-CLIP	22012620
MIRT534493	hsa-miR-4282	PAR-CLIP	22012620
MIRT534494	hsa-miR-548n	PAR-CLIP	22012620
MIRT534495	hsa-miR-548x-3p	PAR-CLIP	22012620
MIRT534496	hsa-miR-548j-3p	PAR-CLIP	22012620
MIRT534497	hsa-miR-548aq-3p	PAR-CLIP	22012620
MIRT534498	hsa-miR-548am-3p	PAR-CLIP	22012620
MIRT534499	hsa-miR-548aj-3p	PAR-CLIP	22012620
MIRT534500	hsa-miR-548ah-3p	PAR-CLIP	22012620
MIRT534501	hsa-miR-548ae-3p	PAR-CLIP	22012620
MIRT534502	hsa-miR-607	PAR-CLIP	22012620
MIRT534503	hsa-miR-2053	PAR-CLIP	22012620
MIRT534504	hsa-miR-3977	PAR-CLIP	22012620
MIRT534505	hsa-miR-6516-3p	PAR-CLIP	22012620
MIRT534506	hsa-miR-3671	PAR-CLIP	22012620
MIRT534507	hsa-miR-7853-5p	PAR-CLIP	22012620
MIRT534508	hsa-miR-105-5p	PAR-CLIP	22012620
MIRT534509	hsa-miR-520c-3p	PAR-CLIP	22012620
MIRT534510	hsa-miR-302e	PAR-CLIP	22012620
MIRT534511	hsa-miR-302a-3p	PAR-CLIP	22012620
MIRT534512	hsa-miR-302c-3p	PAR-CLIP	22012620
MIRT534513	hsa-miR-302d-3p	PAR-CLIP	22012620
MIRT534514	hsa-miR-372-3p	PAR-CLIP	22012620
MIRT534515	hsa-miR-373-3p	PAR-CLIP	22012620
MIRT534516	hsa-miR-302b-3p	PAR-CLIP	22012620
MIRT534517	hsa-miR-520a-3p	PAR-CLIP	22012620
MIRT534518	hsa-miR-520b	PAR-CLIP	22012620
MIRT534519	hsa-miR-520e	PAR-CLIP	22012620
MIRT534520	hsa-miR-520d-3p	PAR-CLIP	22012620
MIRT534521	hsa-miR-520f-3p	PAR-CLIP	22012620
MIRT699850	hsa-miR-4684-5p	HITS-CLIP	23313552
MIRT699851	hsa-miR-6818-3p	HITS-CLIP	23313552
MIRT699852	hsa-miR-593-3p	HITS-CLIP	23313552
MIRT699853	hsa-miR-6895-3p	HITS-CLIP	23313552
MIRT699854	hsa-miR-5699-3p	HITS-CLIP	23313552
MIRT699855	hsa-miR-4421	HITS-CLIP	23313552
MIRT699856	hsa-miR-4637	HITS-CLIP	23313552
MIRT699857	hsa-miR-6732-3p	HITS-CLIP	23313552
MIRT706185	hsa-miR-455-3p	HITS-CLIP	22927820
MIRT706186	hsa-miR-7847-3p	HITS-CLIP	22927820
MIRT706187	hsa-miR-6880-5p	HITS-CLIP	22927820
MIRT706188	hsa-miR-6851-5p	HITS-CLIP	22927820
MIRT706189	hsa-miR-3689d	HITS-CLIP	22927820
MIRT706190	hsa-miR-6134	HITS-CLIP	22927820
MIRT706191	hsa-miR-6500-3p	HITS-CLIP	22927820
MIRT706192	hsa-miR-3614-5p	HITS-CLIP	22927820

Gene ontology (GO)

GO ID	Ontology	Definition	Evidence	Reference
GO:0002474	Process	Antigen processing and presentation of peptide antigen via MHC class I	TAS
GO:0003400	Process	Regulation of COPII vesicle coating	IBA	21873635
GO:0003924	Function	GTPase activity	IBA	21873635
GO:0003924	Function	GTPase activity	TAS
GO:0005515	Function	Protein binding	IPI	32296183
GO:0005525	Function	GTP binding	IEA
GO:0005789	Component	Endoplasmic reticulum membrane	TAS
GO:0005829	Component	Cytosol	TAS
GO:0006886	Process	Intracellular protein transport	IBA	21873635
GO:0006888	Process	Endoplasmic reticulum to Golgi vesicle-mediated transport	IBA	21873635
GO:0006888	Process	Endoplasmic reticulum to Golgi vesicle-mediated transport	TAS
GO:0012507	Component	ER to Golgi transport vesicle membrane	TAS
GO:0016050	Process	Vesicle organization	IBA	21873635
GO:0019886	Process	Antigen processing and presentation of exogenous peptide antigen via MHC class II	TAS
GO:0030127	Component	COPII vesicle coat	IBA	21873635
GO:0032580	Component	Golgi cisterna membrane	IEA
GO:0046872	Function	Metal ion binding	IEA
GO:0048208	Process	COPII vesicle coating	TAS
GO:0061024	Process	Membrane organization	IBA	21873635
GO:0070863	Process	Positive regulation of protein exit from endoplasmic reticulum	IBA	21873635
GO:0070971	Component	Endoplasmic reticulum exit site	IBA	21873635

Other IDs

• MIM: 607690
• HGNC: 10535
• e!Ensembl: ENSG00000152700

Protein

• UniProt ID: Q9Y6B6
• Protein name: GTP-binding protein SAR1b (GTP-binding protein B) (GTBPB)
• Protein function: Involved in transport from the endoplasmic reticulum to the Golgi apparatus. Activated by the guanine nucleotide exchange factor PREB. Involved in the selection of the protein cargo and the assembly of the COPII coat complex.
• Family and domains:

  Pfam

  Accession	ID	Position in sequence	Description	Type
  PF00025	Arf	12 → 197	ADP-ribosylation factor family	Domain

• Sequence:

  MSFIFDWIYSGFSSVLQFLGLYKKTGKLVFLGLDNAGKTTLLHMLKDDRLGQHVPTLHPT
  SEELTIAGMTFTTFDLGGHVQARRVWKNYLPAINGIVFLVDCADHERLLESKEELDSLMT
  DETIANVPILILGNKIDRPEAISEERLREMFGLYGQTTGKGSISLKELNARPLEVFMCSV
  LKRQGYGEGFRWMAQYID

• Sequence length: 198

Pathways

KEGG:

Protein processing in endoplasmic reticulum
Legionellosis

Reactome:

COPII-mediated vesicle transport
MHC class II antigen presentation
Cargo concentration in the ER
Chylomicron assembly
Antigen Presentation: Folding, assembly and peptide loading of class I MHC

Associated diseases

Disease name	Disease term	References
	Abetalipoproteinemia
	Chylomicron retention disease	12692552, 18786134, 19285442, 17945526, 27604308, 21235735, 19274794, 17309654
	Fatty Liver
	Steatohepatitis
	Hypercholesterolemia
	Hypoalbuminemia
	Hypocholesterolemia
	Hypotriglyceridemia
	Malnutrition
	Intellectual Disability
	Retinal Diseases