Rabbit Anti-Crk II, phosphorylated (Tyr221)
CrkII, a cellular homologue of v-Crk, belongs to a family of adaptor proteins with an SH2-SH3-SH3 domain structure that transmits signals from tyrosine kinases (1). The primary function of Crk is to recruit cytoplasmic proteins in the vicinity of tyrosine kinases through SH2-phospho-tyrosine interaction. Thus, the output from Crk depends on the SH3-binding proteins, which include the C3G and Sos guanine nucleotide exchange proteins, Abl tyrosine kinase, DOCK180 and some STE20-related kinases. The variety of Crk-binding proteins indicates the pleiotropic function of Crk (2). The two CrkII SH3 domains are separated by a 54 amino acid linker region, which is highly conserved in Xenopus, chicken and mamalian CrkII proteins (3). Tyrosine 221 in this region is phosphorylated by the Abl tyrosine kinase (4), IGF-I receptor (5) and EGF receptor (6). Once Tyr221 is phosphorylated, CrkII undergoes a change in intramolecular folding and SH2-pTyr interaction, which causes rapid dissociation of CrkII from the tyrosine kinase complex (3).
Applications
Suitable for use in ELISA and Western Blot. Other applications not tested.
Recommended Dilution
Western Blot: 1:1000 Note: for Western Blots incubate membrane with diluted antibody in 5% BSA, 1X TBS, and 0.1% Tween-20 at 4ºC with gentle shaking overnight. Optimal dilutions to be determined by the researcher.
Storage and Stability
May be stored at 4°C for short-term only. For long-term storage, store at -20°C. Aliquots are stable for at least 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
Immunogen
Synthetic phosphopeptide corresponding to residues surrounding Tyr221 of human CrkII. Species sequence homology: mouse and rat 100%.
Form
Supplied as a liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, 0.1mg/ml BSA, 50% glycerol.
Purity
Purified by Protein A and peptide affinity chromatography.
Specificity
Detects endogenous levels of CrkII only when phosphorylated at tyrosine 221 at 42kD. Crossreactivity: Tyr207 phosphorylated CrkL. Does not crossract wth other tyrosine-phosphorylated proteins. Species Crossreactivity: Human and hamster.
