Recombinant Human SAR1B protein is a Human Full Length protein, in the 1 to 198 aa range, expressed in Escherichia coli, with >95% purity and suitable for SDS-PAGE, MS.
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Key facts
- Purity
- >95% SDS-PAGE
- Expression system
- Escherichia coli
- Tags
- His tag N-Terminus
- Applications
- SDS-PAGE, MS
- Biologically active
- No
Amino acid sequence
M G S S H H H H H H S S G L V P R G S H M G S M S F I F D W I Y S G F S S V L Q F L G L Y K K T G K L V F L G L D N A G K T T L L H M L K D D R L G Q H V P T L H P T S E E L T I A G M T F T T F D L G G H V Q A R R V W K N Y L P A I N G I V F L V D C A D H E R L L E S K E E L D S L M T D E T I A N V P I L I L G N K I D R P E A I S E E R L R E M F G L Y G Q T T G K G S I S L K E L N A R P L E V F M C S V L K R Q G Y G E G F R W M A Q Y I D
Reactivity data
| Application | Reactivity | Dilution info | Notes |
|---|---|---|---|
Application SDS-PAGE | Reactivity Reacts | Dilution info - | Notes - |
Application MS | Reactivity Reacts | Dilution info - | Notes - |
Target data
Function
Small GTPase that cycles between an active GTP-bound and an inactive GDP-bound state and mainly functions in vesicle-mediated endoplasmic reticulum (ER) to Golgi transport. The active GTP-bound form inserts into the endoplasmic reticulum membrane where it recruits the remainder of the coat protein complex II/COPII (PubMed:23433038, PubMed:32358066, PubMed:33186557, PubMed:36369712). The coat protein complex II assembling and polymerizing on endoplasmic reticulum membrane is responsible for both the sorting of cargos and the deformation and budding of membranes into vesicles destined to the Golgi (PubMed:23433038, PubMed:32358066, PubMed:33186557). In contrast to SAR1A, SAR1B specifically interacts with the cargo receptor SURF4 to mediate the transport of lipid-carrying lipoproteins including APOB and APOA1 from the endoplasmic reticulum to the Golgi and thereby, indirectly regulates lipid homeostasis (PubMed:32358066, PubMed:33186557). In addition to its role in vesicle trafficking, can also function as a leucine sensor regulating TORC1 signaling and more indirectly cellular metabolism, growth and survival. In absence of leucine, interacts with the GATOR2 complex via MIOS and inhibits TORC1 signaling. The binding of leucine abrogates the interaction with GATOR2 and the inhibition of the TORC1 signaling. This function is completely independent of the GTPase activity of SAR1B (PubMed:34290409).
Alternative names
SARA2, SARB, SAR1B, Small COPII coat GTPase SAR1B, GTP-binding protein B, Secretion-associated Ras-related GTPase 1B, GTBPB
Recommended products
Recombinant Human SAR1B protein is a Human Full Length protein, in the 1 to 198 aa range, expressed in Escherichia coli, with >95% purity and suitable for SDS-PAGE, MS.
Key facts
- Purity
- >95% SDS-PAGE
- Expression system
- Escherichia coli
- Tags
- His tag N-Terminus
- Applications
- SDS-PAGE, MS
- Biologically active
- No
- Accession
- Q9Y6B6-1
- Animal free
- No
- Species
- Human
- Concentration
- Storage buffer
pH: 8
Constituents: 10% Glycerol (glycerin, glycerine), 0.88% Sodium chloride, 0.32% Tris HCl
Sequence info
Amino acid sequence
- M G S S H H H H H H S S G L V P R G S H M G S M S F I F D W I Y S G F S S V L Q F L G L Y K K T G K L V F L G L D N A G K T T L L H M L K D D R L G Q H V P T L H P T S E E L T I A G M T F T T F D L G G H V Q A R R V W K N Y L P A I N G I V F L V D C A D H E R L L E S K E E L D S L M T D E T I A N V P I L I L G N K I D R P E A I S E E R L R E M F G L Y G Q T T G K G S I S L K E L N A R P L E V F M C S V L K R Q G Y G E G F R W M A Q Y I D
- Accession
- Q9Y6B6
- Protein length
- Full Length
- Predicted molecular weight
- 24.8 kDa
- Amino acids
- 1 to 198
- Nature
- Recombinant
- Tags
- His tag N-Terminus
Specifications
- Form
- Liquid
- Additional notes
ab139612 is purified using conventional chromatography techniques.
General info
- Function
Small GTPase that cycles between an active GTP-bound and an inactive GDP-bound state and mainly functions in vesicle-mediated endoplasmic reticulum (ER) to Golgi transport. The active GTP-bound form inserts into the endoplasmic reticulum membrane where it recruits the remainder of the coat protein complex II/COPII (PubMed:23433038, PubMed:32358066, PubMed:33186557, PubMed:36369712). The coat protein complex II assembling and polymerizing on endoplasmic reticulum membrane is responsible for both the sorting of cargos and the deformation and budding of membranes into vesicles destined to the Golgi (PubMed:23433038, PubMed:32358066, PubMed:33186557). In contrast to SAR1A, SAR1B specifically interacts with the cargo receptor SURF4 to mediate the transport of lipid-carrying lipoproteins including APOB and APOA1 from the endoplasmic reticulum to the Golgi and thereby, indirectly regulates lipid homeostasis (PubMed:32358066, PubMed:33186557). In addition to its role in vesicle trafficking, can also function as a leucine sensor regulating TORC1 signaling and more indirectly cellular metabolism, growth and survival. In absence of leucine, interacts with the GATOR2 complex via MIOS and inhibits TORC1 signaling. The binding of leucine abrogates the interaction with GATOR2 and the inhibition of the TORC1 signaling. This function is completely independent of the GTPase activity of SAR1B (PubMed:34290409).
- Sequence similarities
Belongs to the small GTPase superfamily. SAR1 family.
Storage
- Shipped at conditions
- Blue Ice
- Appropriate short-term storage conditions
- -20°C
- Appropriate long-term storage conditions
- -20°C
- Aliquoting information
- Upon delivery aliquot
- Storage information
- Avoid freeze / thaw cycle
Supplementary info
- This supplementary information is collated from multiple sources and compiled automatically.
- Activity summary
SAR1B also known as Secretion-Associated RAS Related GTPase 1B is a small GTPase protein with a molecular mass of approximately 22 kDa. This protein plays an important role in intracellular trafficking specifically in the transport of proteins from the endoplasmic reticulum to the Golgi apparatus. SAR1B is expressed in various tissues with a higher presence in liver and small intestine cells where it participates in the regulation of lipoprotein assembly and secretion.
- Biological function summary
SAR1B is essential for the formation of the coat protein complex II (COPII) facilitating the export of proteins in vesicles from the endoplasmic reticulum. As part of this COPII complex SAR1B assists in the scission of transport vesicles allowing their movement towards the Golgi apparatus. The interaction with other proteins such as SEC23 and SEC24 enhances the specificity of protein selection for transport which is necessary for proper cellular function.
- Pathways
Several important interactions include SAR1B's role in the lipid metabolism and secretion pathways. It collaborates within these pathways to ensure the efficient transport of lipids and proteins necessary for maintaining lipid homeostasis. SAR1B works in coordination with other proteins such as SEC24 and SEC23 underlining its importance in these pathways that are critical for metabolic regulation.
- Associated diseases and disorders
Mutations in SAR1B have been linked with chylomicron retention disease also known as Anderson's disease. This condition is characterized by defective chylomicron secretion leading to symptoms such as fat malabsorption and low blood cholesterol levels. The disease highlights SAR1B's involvement with proteins ensuring proper lipid transport like APOB and MTTP emphasizing its contribution to lipid processing and systemic lipid balance.
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SDS-PAGE - Recombinant Human SAR1B protein (ab139612)
15% SDS-PAGE analysis of ab139612 (3μg).
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