Quantitative Comparisons of Protein Abundances

MCrt -7 huMiaii hrcasl cancer cells in lalwl l m ilium 

Protein name Accession number Isotope ratio MXres/control Densitometry MXres/control 

Alpha tropomyosin P09493 0.10 0.02 Not detected in MXres cells 

It should be noted that these measurements report the relative abrmdance of each protein in the ceU extracts. Isotope ratios and comparative densitometry do not distinguish changes in expression, regulation, or degradation. Follow-up experiments are required to make these distinctions. 

Changes in Plasma Membrane and Nudear Proteins in MCF-7 Cells Resistant to Mitoxantrone 

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