Identification of Protein Markers

Inverse 15N-metabolic labeling/ mass spectrometry for comparative proteomics and rapid identification of protein markers/targets. Rapid Commun. Mass Spectrom. 16, 1389-1397. 

Figure 3. Example of a possible mass spectrometry-based method for the identification of protein markers used to differentiate between species when the genome sequence of one is unknown.

One important issue in medical proteomics is that of individual variations in protein expression and structure (Anderson and Anderson 2002). The protein noise that is generated by individual polymorphic variations can be significant and make the identification of specific marker proteins difficult. 

As an example of the application of these new approaches, we will examine the yeast two-hybrid system for the identification of protein-protein interactions within a cell. This system consists of a yeast genetic assay in which the physical association of two proteins is measured by the reconstitution of a functional transcriptional activator to drive a reporter gene such as P-galactosidase or an auxotrophic marker for selection ° (Figure 5.2). In general. 

Willard-Gallo, K.E., Elouck, D.W., and Loken, M.R., 1988, Analysis of human lymphocyte protein expression. I. Identification of subpopulation markers by two-dimensional polyacrylamide gel electrophoresis. Eur. J. Immunol. 18 1453-1461. 

Identification of mutation altered proteins Protein function control through post-translational modification Medicine Identification of disease markers... 

The immunoassay is another widely used technique that has been applied to a diverse set of proteomic applications, including the identification and quantization of protein markers for diagnosis of diseases where laboratory facilities are not readily available. Immunoassays can be... 

The importance of the need for full identification of potential protein markers is controversial. Most papers on SELDI-TOE-MS for cancer diagnosis have been omitting the identification of potential markers beyond the determination of their approximate molecular mass. In the opinion of some investigators, one does not need individual identified markers as long as consistent protein profiles can be obtained [20]. In other words, the diagnosis of a disease should he considered as a prediction and should not be concerned about etiology. 

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