Perspective of the Fam20C loss- and gain-of-function studies
(A) Phosphorylation of the secreted proteins by the normal expression of Fam20C. (B) In the absence of Fam20C, the lack of phosphorylation of the secreted proteins would alter the molecular configuration, enzyme activity and half-time. (C) The elevated Fam20C expression might result in the over-phosphorylation of the secreted proteins, which could change the microenvironment; whether the overexpressed Fam20C might be leaked into the extracellular space and phosphorylate the proteins in the extracellular space is still in debated.