Final answer:
Gram-negative bacteria use riboswitches to regulate the translation of mRNA, making the correct answer c) Translation. These riboswitches influence how the mRNA interacts with ribosomes, affecting protein synthesis at the translational level.
Step-by-step explanation:
As a general rule, gram-negative bacteria use riboswitches to regulate the translation of mRNA, and gram-positive bacteria use riboswitches to regulate termination. The correct answer is c) Translation.
Riboswitches are a mechanism for bacterial transcription regulation that can abort completion of mRNA synthesis when a metabolite binds to the riboswitch. This regulatory action involves stem-loop structures at the 5' ends of bacterial mRNAs. In the context of gram-negative bacteria, these structures can influence the initiation or continuation of translation by affecting how the mRNA is read by ribosomes.
For gram-positive bacteria, similar riboswitch mechanisms lead to the premature termination of transcription, making the regulation of gene expression a process that does not solely occur at the initiation level, but can also take place during transcription and translation concurrently.