Posttranslational modifications localization

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. 

Sauer A, RobinsonDG. Intracellular localization of posttranslational modifications in the synthesis of hydroxyproline-rich glycoproteins. Peptidyl hydroxylation in maize roots. Planta 1985 164 287-294. 

Kelleher, N.L., Zubarev, R.A., Bush, K., Eurie, B., Eurie, B.C., McLafferty, E.W. and Walsh, C.T. (1999) Localization of labile posttranslational modifications by electron capture dissociation the case of gamma-carboxyglutamic acid. Analytical Chemistry, 71, 4250-4253. 

Posttranslational modification in the form of palmitoylation of the cytosolic domain (see 3.7.2) has been demonstrated for the a- and P-adrenergic receptor. The palmitoylation takes place on a Cys-residue localized at the C-terminus on the membrane iimer side. The modification may possibly serve to anchor the C-terminus in the membrane. 

N. L. Kelleher, R. A. Zubarev, K. Bush, B. Furie, B. C. Furie, F. W. McLafferty, and C. T. Walsh, Localization of labile posttranslational modifications by electron capture dissociation The case of y-carboxyglutamic acid, Anal. Chem., 71 (1999) 4250 1253. 

Posttranslational modification of proteins plays an important role in many physiological processes identifying and localizing these modifications is an essential step in the quest to understand protein function. Posttranslational modifications are not limited to few and select proteins, but occur in... 

Eisenhaber F, Eisenhaber B, Kubina W, Maurer-Stroh S, Neu-berger G, et al. 2003. Prediction of lipid posttranslational modifications and localization signals from protein sequences Big n, NMT and PTS1. Nucleic Acids Res 31 3631-3634. 

Although the physiologic roles of this novel posttranslational modification need to be evaluated, serine pyrophosphorylation likely expands on the already well-defined roles of canonical protein phosphorylation in modifying protein conformation, regulating catalytic activity, determining protein localization, or altering protein-protein interactions. Experiments assessing these possibilities are currently underway. 

Stress-induced biomarkers are quantifiable entities that are altered in stress situations. Such an altered state might be an increase or a decrease in transcription or translation, leading to a change in abundance of mRNA or protein or a posttranslational modification, which may alter the protein activity or cellular localization. 

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