User:Michelle Meyer BC/S1

The S1-interacting RNA is found in the 5’-UTR of rpsA (encoding S1) and regulates S1 synthesis in E. coli at the translational level. The S1 protein is known to interact non-specifically with many RNAs and is required for translation of many transcripts, including its own. The RNA is narrowly distributed, occurring only in Gammaproteobacteria. The conserved GG sequences in loops L1 and L2 are known to be important for regulation and mutagenesis studies have shown that the lower portion of H2 is important for regulation. Toe-printing assays suggest that S1 protein interacts with a variable length AU-rich linker between H2 and H3 and the loop of helix H3. No experimentally verified S1-binding RNA motifs exist in other organisms, but comparative genomics identified an RNA structure preceding rpsA in many Cyanobacteria that bears no resemblance to this RNA.