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Improved detection of quantitative differences using a combination of spectral counting and MS/MS total ion current.

ABSTRACT: Label-free quantitative strategies are commonly used in shotgun proteomics to detect differences in protein abundance between biological sample groups. Here, we have employed a combination of two such approaches, spectral counting (SpC) and average MS/MS total ion current (MS(2) TIC), for the analysis of rat kidney mitochondria in response to metabolic acidosis. In total, 49 proteins were observed to be significantly altered in response to metabolic acidosis (p-value < 0.05). Of these, 32 proteins were uniquely observed as significantly different by SpC, 14 by MS(2) TIC, and only 3 by both approaches. Western blot analysis was performed on a subset of these proteins to validate the observed abundance differences. This study illustrates the utility and ease of combining these two label-free quantitative approaches to increase the number of detected protein abundance differences in the shotgun analysis of complex biological samples.

SUBMITTER: Freund DM

PROVIDER: S-EPMC3834011 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Improved detection of quantitative differences using a combination of spectral counting and MS/MS total ion current.

Freund Dana M DM Prenni Jessica E JE

Journal of proteome research 20130312 4

Label-free quantitative strategies are commonly used in shotgun proteomics to detect differences in protein abundance between biological sample groups. Here, we have employed a combination of two such approaches, spectral counting (SpC) and average MS/MS total ion current (MS(2) TIC), for the analysis of rat kidney mitochondria in response to metabolic acidosis. In total, 49 proteins were observed to be significantly altered in response to metabolic acidosis (p-value < 0.05). Of these, 32 protei ...[more]

PMID: 23445521

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