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  • importx posted an update 4 years, 5 months ago

    1. What is the difference between iTRAQ and other proteomics technologies? How do we choose?Two-dimensional electrophoresis is the earliest and most classic proteomic technology. It is suitable for most samples, but it is not good for strong acid or strong basic protein, and protein with too large or too small molecular weight. In addition, because each sample needs to run alone, It is difficult to avoid the influence of operational errors on the results, which may lead to inaccurate quantification; however, the service price of two-dimensional electrophoresis is relatively cheap and can be used for preliminary screening of sample differences;DIGE has been improved on the basis of two-dimensional electrophoresis, and fluorescent markers and internal standards have been introduced to make the quantification more accurate. However, this technique is also based on the isoelectric point and molecular weight of the protein, so the strong acid or strong basic protein, and the molecular weight Protein separations that are too large or too small are not good.iTRAQ, TMT, label-free and SILAC all use liquid chromatography-mass spectrometry to find differential proteins. Among them, the principle and detection method of iTRAQ serviceand TMT are basically the same, except that different markers are used; TMT has 10 kinds of markers, which can analyze up to 10 different samples, but because the mass of the markers is very similar, Therefore, ultra-high resolution mass spectrometry (Thermo’s QE mass spectrometer) must be used to satisfy the detection, which will inevitably lead to more signal interference, which may affect the accuracy of quantification; label-free is a non-labeled proteomics technology. Because there is no label, its quantification needs to depend on the stability of the operation and the mass spectrometer. The number of proteins identified by this technology will be less than that of iTRAQ technology, and the accuracy of quantification is poor. The advantage is that the service cost is low; SILAC is based on A proteomic approach to stable isotope-labeled cell culture techniques using different isotopic media to culture different groups of cells for in vivo labeling with higher quantitation accuracy than other proteomics techniques; A suitable isotopic medium is essentially used only in mammalian cell lines that can be passaged.From the aspects of quantitative accuracy and applicability, iTRAQ technology has become the most widely used proteomics technology in recent years.