| In this study , we designed experiments to test whether the co activators CREB binding protein ( CBP ) and / or p 300 interact with c Maf , Prox 1 , or Sox 1 to enhance transcription of crystallin genes . ^^^ CBP and p 300 were less effective or ineffective at co activation with Prox 1 or Sox 1 . ^^^ Co immunoprecipitation and mammalian two hybrid experiments revealed that CBP and p 300 bind to c Maf and Prox 1 but not to Sox 1 . ^^^ |