( ( Many ( basic-zipper ( transcription factors ) ) ) ( ( are ( heterodimers ( of ( ( ( two ( different ( polypeptide chains ) ) ) , ) ( each ( containing ( one ( basic-zipper region ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (JJ Many) (JJ basic-zipper) (NN transcription) (NNS factors)) (VP (VBP are) (NP (NP (NNS heterodimers)) (PP (IN of) (NP (NP (CD two) (JJ different) (NN polypeptide) (NNS chains)) (, ,) (NP (NP (DT each)) (VP (VBG containing) (NP (CD one) (JJ basic-zipper) (NN region)))))))) (. .)))
Many basic-zipper transcription factors are heterodimers of two different polypeptide chains, each containing one basic-zipper region.
(ROOT (S (NP (NNP Insulin)) (VP (VBZ is) (VP (VBN made) (PRT (RP up)) (PP (IN of) (NP (CD two) (JJ polypeptide) (NNS chains))))) (. .)))