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bioRxiv · 10.1101/2021.11.24.469687

Number of detected proteins as the function of the sensitivity of proteomic technology in human liver cells

Abstract

The main goal of the Russian part of C-HPP is to detect and functionally annotate missing proteins (PE2-PE4) encoded by human chromosome 18. However, identifying such proteins in a complex biological mixture using mass spectrometry (MS)-based methods is difficult due to the insufficient sensitivity of proteomic analysis methods. In this study, we determined the proteomic technology sensitivity using a standard set of UPS1 proteins as an example. The results revealed that 100% of proteins in a mixture could only be identified at a concentration of at least 10-9 M. The decrease in concentration leads to protein losses associated with technology sensitivity, and no UPS1 protein is detected at a concentration of 10-13 M. Therefore, two-dimensional fractionation of samples was applied to improve sensitivity. The human liver tissue was examined by selected reaction monitoring and shotgun methods of MS analysis using one-dimensional and two-dimensional fractionation to identify the proteins encoded by human chromosome 18. A total of 134 proteins were identified. The overlap between proteomic and transcriptomic data in human liver tissue was ~50%. This weak convergence is due to the low sensitivity of proteomic technology compared to transcriptomic approaches. Data is available via ProteomeXchange with identifier PXD026997.

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BibTeXRIS

Vavilov, N. E., Ilgisonis, E. V., Lisitsa, A. V., Ponomarenko, E. A., Farafonova, T. E., Tikhonova, O. V., Zgoda, V. G., Archakov, A. I.. 2021-11-25. Number of detected proteins as the function of the sensitivity of proteomic technology in human liver cells. https://doi.org/10.1101/2021.11.24.469687

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