Product Name: KEMPtide KinSub
Product Number: PE-01ADW95
Size: 200 µg      Price:29.00
1 mg      $US58.00
5 mg      126.00
Peptide Name: KEMPtide KinSub

Product Use: For assaying the phosphotransferase activity of cAMP-dependent protein kinase catalytic subunit beta (PKAb, UniProt ID P22694).

Peptide Production Method: Solid-phase peptide synthesis

Peptide Sequence: RRRRSIIFI

Peptide Modifications N Terminus: Free amino

Peptide Modifications C Terminus: Amide

Peptide Molecular Mass Calculated: 1215.5 Da

Peptide Purity Percent after Synthesis and Purification: >95

Peptide Appearance: White powder

Peptide Form: Solid

Storage Conditions: -20°C

Peptide Recommended Enzyme: PKA (PRKA)

Scientific Background: PKACa (PRKACA) is a protein-serine/threonine kinase of the AGC group and PKA family. It serves as the alpha catalytic subunit of the cAMP-dependent protein kinase holoenzyme PKA, and it phosphorylates and regulates a very large number of cytoplasmic and nuclear substrate proteins. Phosphorylates hundreds of substrates in the cytoplasm and the nucleus. These include CDC25B, ABL1, NFKB1, CLDN3, PSMC5/RPT6, PJA2, RYR2, RORA, TRPC1 and VASP. It is activated by binding of two cAMP molecules to each of the two associated regulatory subunits in the PKA holoenzyme. Binding of cAMP induces dissociation of the two active catalytic subunits. Phosphorylation of T198 increases phosphotransferase activity. Phosphorylation of S338 plays a key role in stabilizing PKACa. PKACa may be an oncoprotein (OP), although this kinase has also been implicated in inhibiting normal cell proliferation. Gain-of-function mutations in the PRKACA catalytic domain are associated with elevated catalytic activity of the kinase, and have been observed in several cancer types. In particular, a L206R subsitution mutation is observed in cancer and in Cushing's syndrome patients. The gain-of-function mutation is predicted to result in the interruption of the interaction between the catalytic and regulatory subunits of protein kinase A, resulting in a constitutively active PKA. Gain-of-function mutations in the PRKACA gene that lead to consitutive activity of the PKA holoenzyme have been proposed to play an important role in the development of several types of cancer.
References

[1] Songyang Z, Blechner S, Hoagland N, Hoekstra MF, Piwnica-Worms H, Cantley LC.; Use of an oriented peptide library to determine the optimal substrates of protein kinases; Curr Biol. 1994 Nov 1;4(11):973-82. PMID:7874496

[2] Brian J. Yeh, Robert J. Rutigliano, Anrica Deb, Dafna Bar-Sagi, Wendell A. Lim; Rewiring cellular morphology pathways with synthetic guanine nucleotide exchange factors. Nature 2007; 447, 596-600.