| Interaction between the human nuclear cap binding protein complex and hnRNP F . hnRNP F was identified in a screen for proteins that interact with human CBP 80 and CBP 20 , the components of the nuclear cap binding complex ( CBC ) . ^^^ In vitro interaction studies showed that hnRNP F can bind to both CBP 20 and CBP 80 individually . hnRNP F and CBC bind independently to RNA , but hnRNP F binds preferentially to CBC RNA complexes rather than to naked RNA . ^^^ The hnRNP H protein , which is 78 % identical to hnRNP F and also interacts with both CBP 80 and CBP 20 in vitro , does not discriminate between naked RNA and CBC RNA complexes , showing that this effect is specific . ^^^ |