Maize high mobility group proteins bind to CCAAT and TATA boxes of a zein gene promoter

A 216-base pair promoter fragment of the 19-kDa zein storage protein gene pMS1, containing the CCAAT and TATA boxes, was analyzed for its in vitro interactions with purified high mobility group (HMG) proteins from maize endosperm tissue. It was found that the HMG proteins display a preferential binding of A/T-rich DNA regions like their animal counterparts, although the A/T content seems not to be the only determinant for binding specificity. Surprisingly, a specific binding of the HMG proteins occurs at the CCAAT and the TATA boxes as indicated by footprinting experiments.     

Differential gene dosage effects of Ad4BP/SF-1 on target tissue development

Ad4BP/SF-1 (NR5A1) was identified as a key regulator of the hypothalamus-pituitary-gonadal and -adrenal axes. Loss-of-function studies revealed that Ad4BP/SF-1 is essential for the development of these tissues and spleen. Here, we generated transgenic mouse with BAC recombinants carrying a dual promoter and Tet-off system. These recombinants have a potential to express lacZ and Ad4BP/SF-1 in the tissues where endogenous Ad4BP/SF-1 is expressed. However, protein level of Ad4BP/SF-1 varied among the tissues of the transgenic mice and probably thereby the target tissues are affected differentially. The BAC-transgenic mice were applied to rescue Ad4BP/SF-1 KO mouse. Interestingly, the mice successfully rescued the gonad and spleen but failed to rescue the adrenal gland. This variation might be dependent on in part the protein expression levels among the tissues and in part on differential sensitivities to the gene dosage.