A SIMPLE POLYPYRIMIDINE REPEAT ACTS AS AN ARTIFICIAL RHO-DEPENDENT TERMINATOR IN-VIVO AND IN-VITRO

In this paper, we present evidence that an efficient Rho-dependent ter minator can be created by introducing a simple (AG/TC)(n) DNA repeat i nto a transcription unit, The Rho termination activity in vivo and in vitro is dependent on the length and the orientation of the insert. Th e transcription of at least 30 bp of the (AG/TC)(n) repeat in the orie ntation encoding the (rUrC)(n) sequence on the transcript leads to Rho -dependent termination at a downstream non-terminator site, Our result s indicate that the high efficiency of this artificial Rho-dependent t erminator is due to optimal interactions between the (rUrC), RNA seque nce and Rho protein, Thus, our findings strongly suggest that an adequ ate loading site is the primary determinant for Rho termination activi ty and provide a more defined system for future investigations.