Does the metastasis-associated protein S100A4 exist in several charged variants suggesting the presence of posttranslational modifications?
Endogenously expressed S100A4 were shown to exist in several charge variants, which indicates the presence of posttranslational modifications altering the net charge of the protein. The different variants were present in all subcellular compartments and tissues/cell lines examined, suggesting that the described charge variants is a universal phenomenon, and cannot explain the localization of S100A4 in different subcellular compartments. However, the identity of the specific posttranslational modification and its potential contribution to the many reported biological events induced by S100A4, are subject to further studies.
This study suggests a synergistic relationship between depression, cortisol and metabolic syndrome. Hypercortisolemic depression may constitute a specific risk group for the metabolic syndrome.