GMFB is part of the GMF subfamily of the larger actin-binding protein ADF family. GMFB is phosphorylated after phorbol ester stimulation， and is crucial for the nervous system. GMFB causes brain cell differentiation， stimulates neural regeneration and inhibits tumor cell proliferation. GMFB overexpression in astrocytes results in the increase of BDNF production. GMFB expression is increased by exercise， thus BDNF is important for exercise-induction of BDNF.
