Practice question

Anti-Shine-Dalgarno sequence resides at 3' terminal region of 16S rRNA in 30S small subunit, conserved nucleotides 1534 to 1540 with sequence CCUCCU complementary to Shine-Dalgarno AGGAGG in mRNA. Located in a single-stranded tail of 16S, it becomes accessible for base-pairing upstream of start codon, anchoring mRNA with optimal spacing five to nine nucleotides from AUG for initiator tRNA engagement. Mutations altering complementarity impair translation of canonical mRNAs, while engineered systems exploit altered anti-SD for orthogonal translation regulating gene expression synthetically.