|Reactivity||Human Mouse Rat|
|Storage buffer||10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA, 50% glycerol and less than 0.02% sodium azide.|
|Storage||Store at –20°C.|
1. Aspirate media from cultures and Wash the cells with 1X PBS. 2. Lyse cells by adding 1X SDS sample buffer and transfer the extract to a microcentrifuge tube. Keep onice. 3. Sonicate for 10–15 sec to complete cell lysis and shear DNA. 4. Heat a 20 µl sample to 95–100°C for 5 min, then cool on ice. 5. Centrifuge for 5 min (with Microcentrifuge). 6. Load appropriate volumes of samples onto SDS-PAGE gel (loading quantity of protein sample depends on the concentration of extracted proteins). NOTE: At the same time, please load the pre-stained molecular weight markers to determine molecular weights and verify electrotransfer. 7. Electrotransfer to nitrocellulose/PVDF membrane.
Membrane Blocking and Antibody Incubations
1. (Optional) After transfer, wash the transferred membrane with TBS for 5 min at room temperature. 2. Incubate the membrane in the blocking buffer for 1 hr at room temperature. 3. Wash three times for 5 min each with TBST.
b. Antibodies Incubation
1. Incubate membrane and primary antibody (at the appropriate dilution and diluent recommended) in a primary antibody dilution buffer with gentle agitation overnight at 4°C. 2. Wash three times for 5 min each with TBST. 3. Incubate membrane with an appropriate second antibodydissolved in the blocking buffer with gentle agitation for 1 hr at room temperature. 4. Wash three times for 5 min each with TBST. 5. Proceed with detection.
Detection of Proteins
1. After antibodies incubation, Wash membrane three times for 5 minutes in TBST. 2. PrepareECL Reagent (or other chromogenic agents/substrate according to your second antibody). Mix well. 3. Incubate substrate with membrane for 1 minute, remove excess solution (membrane remains wet), wrap in plastic and expose to X-ray film.
NOTE: Do not allow slides to dry at any time during this procedure.
1. Deparaffinize/hydrate sections:
1. Incubate sections in three washes of xylene for 5 min each.
2. Wash sections two times in dH2O for 5 min each.
For Citrate: Heat slides in a microwave submersed in 1X citrate unmasking solution until boiling is initiated; continue with 10 min at a sub-boiling temperature (95°-98°C). Cool slides on bench top for 30 min.
1. Wash sections in dH2O three times for 5 min each.
|Specificity||Phospho-LAT (Y191) Rabbit Recombinant mAb detects endogenous level of total Phospho-LAT (Y191).|
|Background||The adapter molecule LAT (Linker for activation of T cells) is a nucleating site for multiprotein signaling complexes that are vital for the function and differentiation of T cells. LAT is expressed in T cells and in a limited number of other immune cell types (mast cells, natural killer cells, megakaryocytes, platelets, and immature B cells). LAT facilitates the recruitment of many signaling proteins to the plasma membrane where it links receptors, tyrosine kinases and their substrates and other effector molecules together, functioning as a critical activator of T cells. Structurally, LAT is a type III transmembrane protein. LAT is rapidly phosphorylated on tyrosine residues upon TCR engagement. LAT Y171 and Y191 contribute to PLC-γ1 binding and that all four distal LAT tyrosines (132, 171, 191, and 226) were required for optimal PLC-γ1 phosphorylation and downstream calcium influx. Grb2 family members bind Y171, Y191, and Y226 of phosphorylated LAT and recruit a number of signaling proteins to the LAT complex.|