( ( ( Epidermal ( growth factor ) ) ( -LRB- ( EGF -RRB- ) ) ) ( ( ( regulates ( cell proliferation ) ) ( by ( binding ( ( ( its receptor ) , ) ( ( a ( large protein ) ) ( spanning ( ( the thickness ) ( of ( the ( cell membrane ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ Epidermal) (NN growth) (NN factor)) (PRN (-LRB- -LRB-) (NP (NNP EGF)) (-RRB- -RRB-))) (VP (VBZ regulates) (NP (NN cell) (NN proliferation)) (PP (IN by) (S (VP (VBG binding) (NP (NP (PRP$ its) (NN receptor)) (, ,) (NP (NP (DT a) (JJ large) (NN protein)) (VP (VBG spanning) (NP (NP (DT the) (NN thickness)) (PP (IN of) (NP (DT the) (NN cell) (NN membrane))))))))))) (. .)))
Epidermal growth factor (EGF) regulates cell proliferation by binding its receptor, a large protein spanning the thickness of the cell membrane.
(ROOT (S (NP (NNS Cells)) (VP (VBP secrete) (VP (VB factor) (NP (DT that) (NN bind)) (PP (TO to) (NP (NNS receptors))))) (. .)))