Regulatie van genexpressieprocessen

Bacterial replication, transcription, and translation are physically coupled.

Replisome complexes unwind DNA for replication, while RNA polymerases simultaneously transcribe DNA into mRNAs.

Several ribosomes bind the emerging transcript, forming a polyribosome to translate a single mRNA, increasing the protein synthesis turnover.

When the replisome and RNA polymerase move toward each other on opposing DNA strands, they can collide head-on, which stalls replication and transcription, increasing DNA replication errors and supercoiling.

In co-directional collisions, the RNA polymerase and the replisome move in the same direction.

When the RNA polymerases stall the DNA replisome, the helicase activity of additional factors, like transcription-repair coupling proteins, dislodges stalled RNA polymerases.

The replisome helicase propels it forward, minimizing disruptions to replication.

Lastly, defective mRNAs stall translating ribosomes.

Bacterial tmRNA binds such trapped ribosomes and translates the short tmRNA message with a stop codon, resulting in ribosome disassembly via release factors.