( ( In ( fission yeast ) ) ( , ( ( for example ) ( , ( ( extracellular ( mating factors ) ) ( ( activate ( ( Ras , ) ( which ( ( signals ( through ( a ( MAPK cascade ) ) ) ) ( to ( stimulate mating ) ) ) ) ) ) . ) ) ) ) ) )
(ROOT (S (PP (IN In) (NP (NN fission) (NN yeast))) (, ,) (PP (IN for) (NP (NN example))) (, ,) (NP (NN extracellular) (NN mating) (NNS factors)) (VP (VBP activate) (NP (NP (NNP Ras)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ signals) (PP (IN through) (NP (DT a) (NNP MAPK) (NN cascade))) (S (VP (TO to) (VP (VB stimulate) (NP (NN mating)))))))))) (. .)))
In fission yeast, for example, extracellular mating factors activate Ras, which signals through a MAPK cascade to stimulate mating.
(ROOT (S (NP (JJ Enzymatic) (NNS cascades)) (VP (VBP help) (VP (VB amplify) (NP (NP (DT the) (NNS effects)) (PP (IN of) (NP (NN extracellular) (NNS signals)))))) (. .)))