Millipore Sigma Vibrant Logo
Attention: We have moved. Merck Millipore products are no longer available for purchase on MerckMillipore.com.Learn More

HTS119M ChemiSCREEN™ Membrane Preparation Recombinant Human GABAB1b/GABAB2 Receptor

HTS119M
200 units  
Purchase on Sigma-Aldrich

Overview

Replacement Information

Key Spec Table

SpeciesHost CellsProtein Target
Human Chem-1GABAB1b
Description
Catalogue NumberHTS119M
Trade Name
  • ChemiScreen
  • Chemicon
DescriptionChemiSCREEN™ Membrane Preparation Recombinant Human GABAB1b/GABAB2 Receptor
OverviewFull-length human GABBR1b and GPR51 cDNAs encoding GABAB1b/GABAB2
Background InformationThe neurotransmitter γ-aminobutyric acid (GABA) exerts its effects through an ion channel, GABAA, and a GPCR, GABAB. Functional GABAB is a heterodimer composed of the GABAB1 and GABAB2 subunits, which share 35% sequence identity and belong to the class 3 family of GPCRs. The GABAB1 subunit, which exists as splice variants GABAB1a and GABAB1b, binds directly to GABA and is required for agonist activation. The GABAB2 and GABAB1 subunits associate by formation of a coiled coil by their C-terminal tails; this association masks an ER retention sequence in GABAB1 to permit export from the ER and trafficking to the cell surface. In addition to its chaperone function, GABAB2 is the component that couples to Gi to reduce intracellular cAMP. Agonists of GABAB, such as baclofen, are used clinically for treatment of muscle spasticity, migraine headache and musculoskeletal pain (Bowery et al., 2002). Chemicon's GABAB1b membrane preparations are crude membrane preparations made from our proprietary stable recombinant cell lines to ensure high-level of GPCR surface expression; thus, they are ideal HTS tools for screening of antagonists of GABAB1b receptor interactions with its ligand. The membrane preparations exhibit a Kd of 1.15nM for [3H]-CGP 54626A. With 5.0 ug/well GABAB1b Membrane Prep and 7.5nM [3H]-CGP 54626A, a greater than 5-fold signal-to-background ratio was obtained.
References
Product Information
FormatMembranes
PresentationLiquid in packaging buffer: 50 mM Tris pH 7.4, 10% glycerol and 1% BSA with no preservatives.
Packaging method: Membranes protein was adjusted to the indicated concentration in packaging buffer, rapidly frozen, and stored at -80°C.
Quality LevelMQ100
Applications
ApplicationHuman GABAB1b GPCR membrane preparation for Radioligand binding Assays & GTPγS binding.
Key Applications
  • Radioligand binding assay
  • GTPγS binding
Application NotesRadioligand binding assay and GTPγS binding
Biological Information
Entrez Gene Number
Entrez Gene SummaryGamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the mammalian central nervous system. GABA exerts its effects through ionotropic [GABA(A/C)] receptors, to produce fast synaptic inhibition, and metabotropic [GABA(B)] receptors, to produce slow, prolonged inhibitory signals. The GABA(B) receptor consists of a heterodimer of two related 7-transmembrane receptors, GABA(B) receptor 1 and GABA(B) receptor 2. The GABA(B) receptor 1 gene is mapped to chromosome 6p21.3 within the HLA class I region close to the HLA-F gene. Susceptibility loci for multiple sclerosis, epilepsy, and schizophrenia have also been mapped in this region. Alternative splicing of this gene generates 4 transcript variants.
Gene Symbol
  • GABBR1
  • dJ271M21.1.1
  • GABBR1-3
  • GABAB(1e)
  • hGB1a
  • GABABR1
  • dJ271M21.1.2
  • Gb1
  • GABA-B-R1
  • GPRC3A
GPCR ClassC
Host CellsChem-1
Protein TargetGABAB1b
Target Sub-FamilyGABAB
UniProt Number
UniProt SummaryFUNCTION: SwissProt: Q9UBS5 # Isoform 1E function may be to regulate the availability of functional GABA-B-R1A/GABA-B-R2 heterodimers by competing for GABA-B-R2 dimerization. This could explain the observation that certain small molecule ligands exhibit differential affinity for central versus peripheral sites.
COFACTOR: Calcium. Required for high affinity binding to GABA.
SIZE: 961 amino acids; 108320 Da
SUBUNIT: Heterodimer of GABA-B-R1 and GABA-B-R2. Neither of which is effective on its own and homodimeric assembly does not seem to happen. Isoform 1E (without C-terminal intracellular domain) is unable to dimerize via a coiled-coil interaction with GABA-B-R2. Interacts with the leucine zipper of the C-terminal bZIP domain of ATF4 via its C-terminal region.
SUBCELLULAR LOCATION: Cell membrane; Multi-pass membrane protein. Note=Colocalizes with ATF4 in hippocampal neuron dendritic membranes (By similarity). Moreover coexpression of GABA-B-R1 and GABA-B-R2 appears to be a prerequisite for maturation and transport of GABA-B-R1 to the plasma membrane. & Isoform 1E: Secreted (Probable).
TISSUE SPECIFICITY: Highly expressed in brain and weakly in heart, small intestine and uterus. Mostly expressed in granular cell and molecular layer for isoform 1A and in Purkinje cells form isoform 1B. Isoform 1E is predominantly expressed in peripheral tissues as kidney, lung, trachea, colon, small intestine, stomach, bone marrow, thymus and mammary gland.
DOMAIN: SwissProt: Q9UBS5 Alpha-helical parts of the C-terminal intracellular region mediate heterodimeric interaction with GABA-B receptor 2. The linker region between the transmembrane domain 3 (TM3) and the transmembrane domain 4 (TM4) probably play a role in the specificity for G-protein coupling.
SIMILARITY: Belongs to the G-protein coupled receptor 3 family. GABA-B receptor subfamily. & Contains 2 Sushi (CCP/SCR) domains.
Incubation ConditionsMembranes are mixed with radioactive ligand and unlabeled competitor (see Figures 1 and 2 for concentrations tested) in binding buffer in a nonbinding 96-well plate, and incubated for 1-2 h. Prior to filtration, an FC 96-well harvest plate (Millipore cat. # MAHF C1H) is coated with 0.33% polyethyleneimine for 30 min, then washed with 50mM Tris, pH 7.4. Binding reaction is transferred to the filter plate, and washed 3 times (1 mL per well per wash) with Wash Buffer. The plate is dried and counted.

Binding buffer: 1X Hanks' Balanced Salt Solution (HBSS): GIBCO Cat. No. 14175
Radioligand: [3H]-CGP 54626A (American Radiolabeled Chemicals Inc., ART 517)
Wash Buffer: 1X Hanks' Balanced Salt Solution (HBSS): GIBCO Cat. No. 14175

One package contains enough membranes for at least 200 assays (units), where an unit is the amount of membrane that will yield greater than 5-fold signal:background with 3H-labeled CGP 54626A at 7.5nM.
Physicochemical Information
Dimensions
Materials Information
Toxicological Information
Safety Information according to GHS
Safety Information
Table 1. Signal:background and specific binding values obtained in a competition binding assay with 5ug/well of GABAB1b Receptor membrane prep.
Product Usage Statements
5 µg/well
Signal:Background 6.4
Specific Binding (cpm) 2879

SPECIFICATIONS: 1 unit = 5.0 µg membrane preparation
Bmax: 8.49 pmol/mg
Kd: 1.15 nM Usage Statement
  • Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.
Storage and Shipping Information
Storage ConditionsMaintain frozen at -70°C for up to 2 years. Do not freeze and thaw.
Packaging Information
Material Size200 units
Transport Information
Supplemental Information
Specifications
Global Trade Item Number
Catalogue Number GTIN
HTS119M 04053252270512

Documentation

ChemiSCREEN™ Membrane Preparation Recombinant Human GABAB1b/GABAB2 Receptor MSDS

Title

Safety Data Sheet (SDS) 

ChemiSCREEN™ Membrane Preparation Recombinant Human GABAB1b/GABAB2 Receptor Certificates of Analysis

TitleLot Number
CHEMISCREENTM MEMBRANE PREPARATION RECOMBINANT HUMAN GABAB1b/GABAB2 RECEPTOR - 2150335 2150335

References

Reference overviewPub Med ID
International Union of Pharmacology. XXXIII. Mammalian gamma-aminobutyric acid(B) receptors: structure and function
Bowery, N G, et al
Pharmacol Rev, 54:247-64 (2002)  2002

12037141 12037141

Related Products & Applications

Product Families

Related Products By: Brand Facete

Categories

Life Science Research > Drug Discovery and Development > GPCR Cell Lines & Assays > GPCR Membrane Preparations
Life Science Research > Proteins and Enzymes > GPCR Membrane Preparations