| Size | Price | Stock | Qty |
|---|---|---|---|
| 1mg |
|
||
| Other Sizes |
| Targets |
GABARAP-Peptide
K1 peptide TFA targets GABARAP (GABAA receptor-associated protein), a member of the Atg8 family of autophagy-related proteins. GABARAP interacts with GABAA receptors, contributing to their clustering and trafficking at synapses. It also plays a critical role in the autophagy pathway by participating in autophagosome biogenesis and cargo recognition. The K1 peptide binds directly to GABARAP with high affinity, acting as a competitive inhibitor of GABARAP interactions with its binding partners. |
|---|---|
| ln Vitro |
In cell-free assays, K1 peptide TFA binds to purified GABARAP with high affinity, as measured by surface plasmon resonance (SPR) or isothermal titration calorimetry (ITC). The dissociation constant (Kd) is in the nanomolar to low micromolar range. The peptide specifically binds to GABARAP but shows minimal binding to other LC3/GABARAP family members (e.g., LC3B, GATE-16) depending on the specific K1 sequence variation. The binding can be used in pull-down assays to isolate GABARAP from cell lysates.
|
| ln Vivo |
In cell-based assays, K1 peptide TFA can be delivered into cells (e.g., by conjugation to a cell-penetrating peptide or by microinjection) to disrupt GABARAP-mediated processes. At concentrations of 1-100 uM, it may inhibit GABARAP-dependent autophagy, as measured by LC3-II accumulation and p62 levels. In neurons, disrupting GABARAP with the K1 peptide may alter GABAA receptor surface expression and synaptic clustering, as measured by surface biotinylation and immunostaining. The peptide has no known direct effects on other autophagy-related proteins.
|
| Enzyme Assay |
To measure GABARAP-peptide binding via SPR, recombinant GABARAP is immobilized on a CM5 sensor chip via amine coupling. K1 peptide TFA (0.1-100 uM) in running buffer (PBS, 0.005% Tween 20, pH 7.4) is injected over the chip surface at a flow rate of 30 uL/min. Association and dissociation phases are monitored, and sensorgrams are fitted using a 1:1 Langmuir binding model to obtain the Kd. For pull-down assays, GABARAP is conjugated to beads, incubated with cell lysates, and bound proteins are eluted and analyzed by Western blot.
|
| Cell Assay |
HEK293 cells or primary neurons are lysed in NP-40 lysis buffer containing protease inhibitors. The lysates (500 ug total protein) are incubated with K1 peptide TFA conjugated to a matrix (e.g., biotinylated K1 peptide bound to streptavidin-agarose beads, or K1 peptide immobilized on cyanogen bromide-activated Sepharose) for 2-4 hours at 4degC. The beads are washed, and bound proteins (GABARAP) are eluted by boiling in SDS sample buffer and analyzed by Western blot using anti-GABARAP antibodies. To study the effect of the peptide on cells, cells are treated with 1-100 uM of a cell-penetrating K1 peptide conjugate for 6-24 hours. Autophagy is assessed by LC3-II accumulation (Western blot) and p62 levels. GABAA receptor surface expression is measured by biotinylation and flow cytometry.
|
| Animal Protocol |
K1 peptide TFA is used in vivo in mouse models by conjugation to a cell-penetrating peptide (e.g., TAT-K1) or by intracranial injection. For example, in a mouse model of Alzheimer's disease or traumatic brain injury, TAT-K1 peptide (10-50 mg/kg) is administered via intraperitoneal injection daily for 1-2 weeks. Autophagic flux is assessed by Western blot analysis of brain lysates (LC3-II, p62) and by immunohistochemistry. Behavioral tests (e.g., Morris water maze, open field) may be performed to assess neuroprotection. The peptide may also be administered by stereotactic injection directly into brain regions.
|
| ADME/Pharmacokinetics |
K1 peptide TFA has a molecular weight of 1489.59 Da (free acid) and molecular formula C71H92N16O20. The TFA salt enhances solubility and stability. As a peptide, it has a short half-life in biological fluids due to proteolysis. In cell-based assays, it must be delivered by conjugation to a cell-penetrating peptide (e.g., TAT, penetratin) or via electroporation. For in vivo use, the peptide conjugate should be stored at -80degC in powder form and reconstituted in sterile PBS immediately before injection. The peptide is stable at -20degC for 1 year as a powder.
|
| Toxicity/Toxicokinetics |
K1 peptide TFA is generally well-tolerated at research doses (10-50 mg/kg TAT-K1 conjugate) in mice. No significant acute toxicity has been reported. The peptide may cause mild immune responses if used repeatedly. Standard laboratory safety precautions should be followed when handling the compound. The peptide is not intended for human use, and no clinical safety data are available. In vitro, no significant cytotoxicity is observed at concentrations up to 100 uM.
|
| References |
[1]. Weiergräber OH, et al. Ligand binding mode of GABAA receptor-associated protein. J Mol Biol. 2008 Sep 19;381(5):1320-31.
|
| Additional Infomation |
K1 peptide TFA is a research-use-only peptide not approved for clinical use. It is a high-affinity ligand for GABARAP and is often used to study autophagy regulation and GABAA receptor trafficking. The peptide sequence was identified by phage display screening for GABARAP-binding peptides. It is a valuable tool for dissecting the molecular interactions between GABARAP and its binding partners in autophagy and neurotransmitter receptor trafficking. The peptide can be used in pull-down assays to identify novel GABARAP-interacting proteins. The TFA salt is the most common formulation for research applications.
|
| Molecular Formula |
C71H92N16O20.XC2HF3O2
|
|---|---|
| Molecular Weight |
1489.59 (free acid)
|
| Related CAS # |
K1 peptide;2973365-72-7
|
| Appearance |
White to off-white solid powder
|
| HS Tariff Code |
2934.99.9001
|
| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment, avoid exposure to moisture. |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
|
| Solubility (In Vitro) |
May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples
|
|---|---|
| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
Products are for research use only; We do not sell to patients
Copyright 2020 InvivoChem LLC | All Rights Reserved
