Rho factor

• UniProt: P0AG30

Of ρ - factor ( rho factor ) is a protein that may terminate in prokaryotes RNA transcription. It acts as an ATP-dependent helicase, which moves along the direction of newly synthesized RNA 3 'end of the RNA, and finally detaches from the DNA, thus completing the RNA synthesis.

In E. coli is a Rho ~ 275 kD hexamer consists of six identical subunits, each of which is an RNA -binding and ATP -binding domain comprises. The subunits are arranged around a cavity in the center through which passes the RNA strand. The protein binds to an approximately 70 -nucleotide-long region of the newly synthesized single-stranded RNA, which is rich in cytosine and poor in guanine. From there, the enzyme moves with consumption of ATP for transcription bubble in which the RNA is synthesized by the RNA polymerase. Here, it acts as a helicase, which separates the RNA strand of the DNA and the polymerase.

The binding site, also rut - rho utilization site called, is located above the transcription end. Have been identified, without having to provide a different consensus sequence binding sites. There may be a more specific termination sequence at which the polymerase is slower so that it can be obtained from the Rho factor; However, the kinetics are complex and not yet fully analyzed.