FIG. 3.

Both TAF9 and TAF9b are expressed at the mRNA and protein levels in several human cell lines. (A) RNA was prepared from the indicated human cell lines, and RT-PCR analysis was carried out with common 5′ primers specific to TAF9 and TAF9b mRNA and with different 3′ primers specific for each transcript. In addition, primers amplifying the GAPDH (glyceraldehyde-3-phosphate dehydrogenase) transcript were used to normalize the amount of RNA used. Tib60 is a mouse cell line and thus should be considered a negative specificity control in this experiment. PCR products were analyzed on a 1.5% agarose gel. (B) Whole-cell extracts were prepared from the indicated cell lines, and then protein samples were analyzed by Western blot with the indicated antibodies. Protein levels were normalized using an anti-β-actin monoclonal antibody.