( ( The scientists ) ( also ( ( examined ( ( four ( other markers ) ) ( involved ( in ( cell ( cycle regulation ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (DT The) (NNS scientists)) (ADVP (RB also)) (VP (VBD examined) (NP (NP (CD four) (JJ other) (NNS markers)) (VP (VBN involved) (PP (IN in) (NP (NN cell) (NN cycle) (NN regulation)))))) (. .)))
The scientists also examined four other markers involved in cell cycle regulation.
(ROOT (S (NP (NNS Cells)) (VP (VBP have) (NP (CD four) (NNS cycles))) (. .)))