FIG. 1.

The carboxyl-terminal and amino-terminal halves of CA150, containing FF repeats and WW domains, respectively, are required for repression of the α₄-integrin promoter. CA150 test constructs were overexpressed in 293T cells with an α₄-integrin promoter driving the expression of the CAT reporter gene to assay CA150-mediated repression. CA150 constructs shown on the left indicate the domains contained in each protein. CA150 WT is the wild-type 1,098-amino-acid protein. CA150(1–663) and CA150(590–1098) contain amino acids 1 to 663 and 590 to 1098, respectively. CA150 protein domain abbreviations: PP, polyproline-rich region; WW, WW domain; QA, glutamine-alanine repeats; NLS, nuclear localization signal; FF, FF repeats. The percent inhibition of CAT activity was calculated as described in Materials and Methods. The activity of each construct was assayed at least three times independently, and the error bars represent the standard deviation. The right panel is a representative Western blot, against the amino-terminal T7 epitope tag of each protein, showing the expression of each construct.