- Two ways to represent protein data are used in literature,
namely, correction by non-phosphorylated protein levels and
by a proper loading control (i.e.,β-actin). The latter might be
problematical if total protein levels are not displayed. Never-
theless, it is important to keep in mind that independent of the
origin in the phosphorylation status (increased/decreased
upstream kinase/phosphatase activity or increased/decreased
non-phosphorylated levels), the activity of the enzyme
(increased/decreased) is what matters.
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