Global phosphorylation

Histone phosphorylation is a common posttranslational modification fond in histones, primarily on the N-terminal tails. Phosphorylation sites include serine and threonine residues, tyrosine phosphorylation has not been observed so far. Some phosphorylation events occur locally whereas others occur globally throughout all chromosomes during specific events like mitosis. Histone phosphorylation is catalyzed by kinases. Removal of the phosphoryl groups is catalyzed by phosphatases. 

Attempts have been made to define the phosphorylation status of protein on a global scale.71 Most approaches involve the use of phospho-specific antibodies to enrich for proteins with phos-phorylated residues. Due to the availability of excellent antibodies that react with phosphotyrosines,... 

Hellstrand That is what I am getting at. There are a lot of phase shifts in this system. One observation we have made is that under hypoxia we see a decrease in amplitude but an increase in frequency of the waves. We are trying to model a case where this would account for reduction of force simply on the basis of non-linearity of the [Ca2+] versus myosin phosphorylation versus force reactions. It seems intuitively that this could explain why there can be a reduction in force although there is no reduction in the overall level of global Ca2+. Is amplitude modulation something that people have seen ... 

H Mostafavi, S Austermann, W-G Forssmann, K Adermann. Synthesis of phospho-urodilatin by combination of global phosphorylation with the segment coupling approach. (Fmoc-Ser-OH + TBTU + H-Xaa-OR) Int J Pept Prot Res 48, 200, 1996. 

RegA Response regulator Repressor Phosphorylated by RegB-P RegA 34 59 Global regulation... 

A major development in global phosphorylation was realized through the application of highly reactive diorganyl dialkylphosphoramidites for the simple phosphite-triester phosphorylation of target sites. 76 While this phosphorylation procedure has been success-... 

The presence of tumor necrosis factor a directly leads to apoptosis via interaction with the tumor necrosis factor receptor, one of a class of receptors referred to as death receptors. NF-kB, which must enter the nucleus to initiate apoptosis, is a transcription factor sequestered in the cytoplasm by inhibitor of kB (IkB). The binding of TNFa to its receptor leads to the ubiquitin-dependent proteolysis of IkB, allowing NF-kB to enter the nucleus. The activation of apoptosis results directly from the stimulation of NF-kB, a transcription factor whose phosphorylation is controlled by vanadium compounds. In a global gene expression study, it was found that diabetes increased the formation of IkB, whereas vanadium compound treatment lowered the production of this inhibitor [101]. The activation of the TNFR also activates the caspase proteins, a class of proteases that cleave proteins after specific aspartate residues. 

Key Words Global phosphorylation phosphopeptide phosphoramidite phosphoserine phosphothreonine phosphotyrosine. 

Fig. 2. Chromatograms of the double phosphorylated peptide H-CXVAVVRT (P)PPKS(P)PSSAK-NH2 (X = -aminohexanoic acid, T(P) = phosphothreonine, and S(P) = phosphoserine) synthesized by the global phosphorylation strategy (see Subheading 3.3.) after precipitation with diethyl ether (upper panel) and after purification on a preparative Jupiter Ci8-column (lower panel). For chromatographic conditions see Fig. 1. The by-products eluting at 14.9 min and 17.7 min are most likely impurities of the amidite reagent and not formed by the peptide.

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