Top-Down Proteomics and the Challenges of True Proteoform Characterization.

Po, Allen ORCID: 0000-0001-5915-3747 and Eyers, Claire E ORCID: 0000-0002-3223-5926 (2023) Top-Down Proteomics and the Challenges of True Proteoform Characterization. Journal of proteome research, 22 (12). pp. 3663-3675.

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Official URL: http://dx.doi.org/10.1021/acs.jproteome.3c00416

Abstract

Top-down proteomics (TDP) aims to identify and profile intact protein forms (proteoforms) extracted from biological samples. True proteoform characterization requires that both the base protein sequence be defined and any mass shifts identified, ideally localizing their positions within the protein sequence. Being able to fully elucidate proteoform profiles lends insight into characterizing proteoform-unique roles, and is a crucial aspect of defining protein structure-function relationships and the specific roles of different (combinations of) protein modifications. However, defining and pinpointing protein post-translational modifications (PTMs) on intact proteins remains a challenge. Characterization of (heavily) modified proteins (>∼30 kDa) remains problematic, especially when they exist in a population of similarly modified, or kindred, proteoforms. This issue is compounded as the number of modifications increases, and thus the number of theoretical combinations. Here, we present our perspective on the challenges of analyzing kindred proteoform populations, focusing on annotation of protein modifications on an "average" protein. Furthermore, we discuss the technical requirements to obtain high quality fragmentation spectral data to robustly define site-specific PTMs, and the fact that this is tempered by the time requirements necessary to separate proteoforms in advance of mass spectrometry analysis.

Item Type:	Article
Uncontrolled Keywords:	Proteins, Proteome, Proteomics, Protein Processing, Post-Translational, Amino Acid Sequence, Tandem Mass Spectrometry
Divisions:	Faculty of Health and Life Sciences Faculty of Health and Life Sciences > Institute of Systems, Molecular and Integrative Biology
Depositing User:	Symplectic Admin
Date Deposited:	22 Nov 2023 15:29
Last Modified:	06 Jan 2024 01:25
DOI:	10.1021/acs.jproteome.3c00416
Open Access URL:	https://doi.org/10.1021/acs.jproteome.3c00416
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3176957