Terminal Amine Isotopic Labeling of Substrates (TAILS)

TAILS is a novel multiplex quantitative proteomics platform for the determination of N-terminomes and the system-wide identification of protease substrates and cleavage sites in complex biological samples. In this method, all natural and cleaved N-termini and lysines in a proteome (exposed or not exposed to a protease) are blocked by differential isotopic labeling. Pooled samples are trypsinized and then, to reduce sample complexity, incubated with an aldehyde-derivatized amine-reactive polymer that removes all unlabeled peptides. TAILS therefore focuses on the proteomic analysis of N-termini of all proteins, which together form the N-terminome. Protease-generated neo-N-termini are only present in the protease-exposed but not in the control sample and are characterized by a high ratio in relative quantification of corresponding isotopic labels. Thereby, the use of isobaric tags for relative and absolute quantitation (iTRAQ) allows the analysis of up to eight samples in a single experiment.

Resources

CLIPPER software
CLIPPER v1.0
Tutorial sample data (including mzXML)

UPDATES:
01/10/2013 New installer for TPP v4.6 OCCUPY rev 1 click here

TAILS Annotator software
TAILS Annotator 1.0

References

Original Paper:

Kleifeld O, Doucet A, auf dem Keller U, Prudova A, Schilling O, Kainthan RK, Starr AE, Foster LJ, Kizhakkedathu JN, Overall CM (2010) Isotopic labeling of terminal amines in complex samples identifies protein N-termini and protease cleavage products. Nat Biotechnology 28(3), 681-8

Prudova A, auf dem Keller U, Butler GS, Overall CM (2010) Multiplex N-terminome analysis of MMP-2 and MMP-9 substrate degradomes by iTRAQ-TAILS quantitative proteomics. Mol Cell Proteomics 9(5), 894-911

auf dem Keller U, Prudova A, Gioia M, Butler GS, Overall CM (2010) A statistics-based platform for quantitative N-terminome analysis and identification of protease cleavage products. Mol Cell Proteomics 9(5), 912-927

Step by Step Protocol:

Kleifeld O, Doucet A, Prudova A, auf dem Keller U, Gioia M, Kizhakkedathu JN, Overall CM (2011) Identifying and quantifying proteolytic events and the natural N terminome by terminal amine isotopic labeling of substrates. Nature Protocols 6(10), 1578-611

CLIPPER paper:

auf dem Keller U and Overall CM (2012) CLIPPER-An add-on to the Trans-Proteomic Pipeline for the automated analysis of TAILS N-terminomics data. Biol Chem 393(12), 1477-1483