Modifier	Substrate	Residue	Sequence	Mechanism/Effect	PMID	Interaction ID
GSK3B	FBXL21P	Thr33	FYSSLNQtHTHTVLL	phosphorylation up-regulates activity	32937135	SIGNOR-264851

Enzyme	Effect	Phosphosite	Effect	Target	PMID	Interaction ID
GSK3B	phosphorylation up-regulates →	FBXL21P PThr33	phosphorylation up-regulates →	FBXL21P	32937135	SIGNOR-264851

Regulator	Mechanism/Effect	Target	SIGNOR-ID
GSK3B	phosphorylation → up-regulates activity	FBXL21P	SIGNOR-264851