Rho binds to a sequence within the transcript upstream of the site of termination. This sequence is called a rut site (an acronym for rho utilization).

TLS Online TPP Program

#Id: 766

#Unit 3. Fundamental Processes

Two bases in the non-template strand of the –10 element (A11 and T7) flip out from their base-stacking interactions and instead insert into pockets within the sigma protein where they make more favorable interactions for OPC

TLS Online TPP Program

#Id: 767

#Unit 3. Fundamental Processes

Abortive transcription is when RNA Polymerase makes short transcripts, typically shorter than 10 nucleotides (nt), while still bound at the promoter.

TLS Online TPP Program

#Id: 768

#Unit 3. Fundamental Processes

In abortive transcription, an RNA chain forms without movement of the enzyme down the template by scrunching DNA

 

TLS Online TPP Program

#Id: 769

#Unit 3. Fundamental Processes

After release of the abortive product, the enzyme again begins synthesizing RNA at position +1 called as Initiation

TLS Online TPP Program

#Id: 770

#Unit 3. Fundamental Processes

Once an enzyme makes a transcript longer than 10 nucleotides, it is said to have escaped the promoter. At this point, it has formed a stable ternary complex, containing enzyme, DNA, and RNA. This is the transition to the elongation phase.

TLS Online TPP Program

#Id: 771

#Unit 3. Fundamental Processes

During RNA transcript formation, DNA makes its 90° turn at the active site.