Preparation of polyclonal antibody specific for BRD7 and detection of its expression pattern in the human fetus.

BRD7 is a novel bromodomain gene. It plays critical role in cell growth, cell cycle progression, and signal-dependent gene expression. Overexpression of the BRD7 gene in nasopharyngeal carcinoma cells is effective to inhibit cell growth and cell cycle progression from G1 to S phase. However, little is known about its bio-functions because of the unavailability of a specific BRD7 antibody. In this study, for the first time, we generated a highly specific BRD7 antibody. It is able to specifically recognize recombinant GST-BRD7N protein with a molecular mass of 65 kDa and recognize BRD7-Myc and endogenously expressed BRD7 protein with an approximate molecular mass of 75 kDa, which corresponds well with the calculated molecular mass of the BRD7 protein. More importantly, with these antisera, we analyzed BRD7 distribution in the human fetus by Western blot and immunohistochemistry assays. Obvious nuclear expression of BRD7 protein presents in human cerebellum, pancreas, intestines, liver, and kidney. Cardiomyocyte shows high cytoplasm expression of the BRD7 protein. Weak nuclear expression of the BRD7 protein is found in human cerebrum, lung, and stomach. These data may help to further study the cellular role of the BRD7 gene. In particular, the prepared BRD7 antibody will be helpful for studying the bio-functions of endogenously expressed BRD7 protein.