What occurs when an RNA binding protein blocks access to the SD sequence?

When an RNA binding protein blocks access to the Shine-Dalgarno (SD) sequence, translation is inhibited. The Shine-Dalgarno sequence is a crucial part of the mRNA in prokaryotic organisms that helps initiate translation by pairing with the 16S rRNA of the ribosome. If an RNA binding protein binds to the mRNA and obstructs the SD sequence, the ribosome is unable to attach properly to the mRNA, thus preventing the initiation of translation.

This inhibition is significant because it directly affects the synthesis of proteins from that mRNA. The binding of such proteins can serve as a regulatory mechanism, ensuring that translation occurs only under certain conditions when the mRNA is accessible. Therefore, the blocking of the SD sequence by an RNA binding protein leads to a decrease in protein production, confirming that translation is inhibited.