pBlue TOPO™ TA Expression Kit - FAQs

Does the BGH poly A region in your vectors have a splice donor and splice acceptor (and therefore an intron)? What is the general function of the BGH polyA region?

There is no intron in the BGH polyA sequence. The BGH polyA signal (bases 1028-1252 in pcDNA3.1 vector) is the sequence that allows for polyadenylation of the RNA transcript. It is described in the following reference: The 3'-flanking sequence of the bovine growth hormone gene contains novel elements required for efficient and accurate polyadenylation. J Biol Chem.1992 Aug 15;267(23):16330-4

The reference states that the 3' untranslated region leading up to the poly adenylation core sequence (AATAAA) contains unique disperse non-consensus elements (consensus elements are poly U and GU-rich tracts) that serve to increase the efficiency of polyadenylation to a high degree, and that a 9-base sequence downstream of the core sequence facilitates efficient cleavage of the RNA strand. This leads to more stable and higher-abundance transcripts.