Absolute quantitation of post-translational modifications.

Ruchi Chaube

doi:10.3389/fchem.2014.00058

Abstract

Absolute quantitation of post-translational modifications.

Highlights

The cell’s fate is largely governed by the dynamics of cellular events, brought about by the interplay of various proteins, in which post-translational modifications (PTMs) play a key role
For the metabolic labeling of proteins, the cell cultures are grown in the presence of naturally abundant amino acids, and amino acids labeled with heavy isotopes (13C, 15N and/or deuterium), this method is known as stable isotope labeling with amino acids in cell culture (SILAC)
In the post-metabolic labeling approach, such as isotope-coded affinity tag (ICAT) (Sethuraman et al, 2004), isobaric tag for relative and absolute quantitation (Gan et al, 2007) and tandem mass tag (TMT) (Thompson et al, 2003), the peptide fragments generated by proteolytic digestion of proteins are chemically derivatized at an amino acid side chain; cysteines thiols (ICAT) or primary amines and quantitation of peptides between the samples is done by comparing the ion intensities of the tags in the MS/MS spectrum

Summary

Introduction

The cell’s fate is largely governed by the dynamics of cellular events, brought about by the interplay of various proteins, in which post-translational modifications (PTMs) play a key role. Differential labeling of samples with stable isotopes or in the label-free approach the peak intensity of a peptide ion or identification frequency of the peptides of a particular protein is used for measurement.

Results

Conclusion