Identification
These small RNA were identified computationally by searching the genome of E. coli for intergenic regions of high sequence identity (sequence conservation) with the genomes of closely related bacteria (several salmonella species and Klebsiella pneumoniae). This data was combined with microarray expression analysis and potential novel ncRNAs identified. The expression of novel ncRNA of interest was confirmed by northern blotting.
In this large scale screen these ncRNAs were simply referred to as candidates 43, 55 and 61. These 3 ncRNA appear to be highly homologous and are derived from a repeat region of the genome. Each of the ncRNA contains a short stretch homologous to boxC, a repeat element of unknown function present in 50 copies or more within the genome of E. coli.
Read more about this topic: Sib RNA