Catalog # IX1035


phospho-IκBα (Tyr-42)

Blocking Peptide

Application Dilution
Blocking1:1000
ELISA50 ng/well

Size 50 μg

$55

The NF-κB/Rel transcription factors are present in the cytosol in an inactive state complexed with the inhibitory IκB proteins. Activation of IκBα occurs through both serine and tyrosine phosphorylation events. Activation through phosphorylation at Ser-32 and Ser-36 is followed by proteasome-mediated degradation, resulting in the release and nuclear translocation of active NF-κB. This pathway of IκBα regulation occurs in response to various NF-κB-activating agents, such as TNFα, interleukins, LPS, and irradiation. An alternative pathway for IκBα regulation occurs through tyrosine phosphorylation of Tyr-42 and Tyr-305. Tyr-42 is phosphorylated in response to oxidative stress and growth factors. This phosphorylation can lead to degradation of IκBα and NF-κB-activation. In contrast, Tyr-305 phosphorylation by c-Abl has been implicated in IκBα nuclear translocation and inhibition of NF-κB-activation. Thus, tyrosine phosphorylation of IκBα may be an important regulatory mechanism in NF-κB signaling.

 

References

Waris et al. (2003) J Biol Chem 278(42):40778.
Bui, N.T. et al. (2001) J Cell Biol 152(4):753.
Finco, T.S. et al. (1994) Proc. Natl. Acad. Sci. USA 91:11884.

Phospho-IκBα (Tyr-42) synthetic peptide corresponds to amino acid residues around tyrosine 42 of human IκBα. This peptide sequence has low homology to other IκB proteins, but does have some homology to unrelated proteins that may have a conserved tyrosine phosphorylation motif.

*For more information, see UniProt Accession P25963
Blocking Peptide is supplied in 50µl phosphate-buffered saline and 0.05% sodium azide.

The products are are safely shipped at ambient temperature for both domestic and international shipments. Each product is guaranteed to match the specifications as indicated on the corresponding technical data sheet. Please store at -20C upon arrival for long term storage.

The peptide is specifically recognized by IκBα (Tyr-42) phospho-specific antibody (IP1031) in ELISA, and has been shown to block the reactivity of IP1031 during Western blot. In addition, the peptide is recommended for use in blocking IP1031 reactivity in immunocytochemistry.

*All molecular weights (MW) are confirmed by comparison to Bio-Rad Rainbow Markers and to western blot mobilities of known proteins with similar MW.

Western blot analysis of A431 cells treated with pervanadate (1 mM) for 30 min. Blots were probed with anti-IκBα (lane 1), anti-IκBα (Tyr-42) (IP1031; lanes 2-5), or anti-IκBα (Tyr-305) (IP1041; lanes 6-9). In some lanes, the antibodies were used in the absence (lane 2 & 6) or presence of IκBα (Tyr-42) (lane 3 & 8) or IκBα (Tyr-305) (lane 4 & 7) blocking peptides, or BSA conjugated to phospho-tyrosine (lane 5 & 9).



This kit contains:

KIT SUMMARY