Phosphorylation sites, protein

FIGURE 25.4 Models of the acetyl-CoA carboxylase polypeptide, with phosphorylation sites indicated, along with the protein kinases responsible. Phosphorylation at Ser " is primarily responsible for decreasing the affinity for citrate. 

Protein Kinase C. Figure 1 Domain structure of PKC family members showing regulatory modules (pseudosubstrate sequence and C1, C2, and PB1 domains) and the kinase core. Shown below are the structures of the C1 domain of PKC 5 with bound phorbol (purple), the C2 domain of PKC (3 with bound Ca2+ (pink spheres), and the recently solved structure of the kinase domain by Grant and coworkers [1] of PKC pil with phosphorylation sites indicated in pink. Figure adapted from Newton (2003). 

When 14-3-3s were first identified as phosphorylation dependent binding proteins (note that a selection of non-phosphorylated targets are known), target protein phosphorylation sites were mapped and it was immediately apparent that 14-3-3s bound preferentially to specific phosphorylation motifs. The advent of oriented... 

TRAM is subject to control through phosphorylation by protein kinase C-e. It is phosphorylated on serine 16 which is located close to the myristoylation site which is TRAM cannot signal without this phosphorylation or if the myristoylation site has been mutated. 

HSFl phosphorylation must be sensitive to nonheat inducers of HSF-DNA binding activity because HSFl phosphorylation can be achieved at 37 °C by other inducers of the HS response. HSF 1 contains polypeptide sequences that could serve as substrates for well characterized protein kinases, but few of these are known to be heat inducible. One family of protein kinases, the S6 protein kinases, have already been shown to exhibit heat inducible activity however, their peak level of activity during HS occurs well after the maximal induction of HSF phosphorylation (Jurivich et al., 1991). Thus, other protein kinases are likely to be directly linked to the phosphorylation of HSF. Some of the putative protein phosphorylation sites on HSF include motifs for protein kinase C, casein kinase, and enterokinase. There are tyrosine sequences that match substrates for known tyrosine kinases, but whether these residues are accessible to phosphorylation is not established. 

Fig. 4.1 Topological organization of the vanilloid receptor TRP VI. Highlighted are the molecular determinants of TRPVl regulation, such as recognition (binding) domains for capsaicin and acids, and phosphorylation sites for protein kinases. Numbers designate the key amino acid residues deduced from the rTRPVl primary sequence. Adapted from Ferrer-Montaniel, A. et al. (2004) Fur. J. Biochem. 271, 1820—1826.

Pickham, K. M., Meyer, A. N., Li, J and Donoghue, D. J. (1992). Requirement of mosx protein kinase for meiotic maturation of Xenopus oocytes induced by a cdc2 mutant lacking regulatory phosphorylation sites. Mol. Cell. Biol. 12 3192-3203. 

Neubauer, G., and Mann, M. (1999). Mapping of phosphorylation sites of gel-isolated proteins by nanoelectrospray tandem mass spectrometry potentials and hmitations. Anal. Chem. 71, 235-242. 

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