FIG. 1.

Maf and Sox proteins synergistically stimulate γF- but not αA-crystallin promoter activity. (A) Maf activation of αA-crystallin promoter activity is not stimulated by Sox proteins. The indicated amounts (in micrograms) of plasmids encoding the proteins indicated below the bars were transfected into mouse αTN4 lens epithelial cells together with a CAT reporter gene controlled by the αA crystallin promoter. The reporter gene activities were measured, and the efficiencies of transcription activation were calculated relative to cells transfected with the αA-crystallin reporter gene alone. The data in this and subsequent panels represent averages and standard deviations for at least three independent experiments, each with triplicate samples, performed on different days. (B) Maf and Sox proteins synergistically activate the γF-crystallin promoter. The efficiencies of transcription activation by the proteins indicated below the bars were measured at the γF-crystallin promoter as described for panel A. (C) Sequence of the region of the γF-crystallin promoter that contains Sox and Maf recognition elements. The Sox recognition element is double underlined, and two potential Maf recognition elements are overlined and underlined, respectively. The dashed line indicates the nonconsensus core of the Maf recognition sequences.