Small non-coding RNAs in Sinorhizobium meliloti
Small non-coding RNAs (sRNAs) help bacteria tune gene activity to environmental changes. Sinorhizobium meliloti, a helpful Alphaproteobacterium, partners with certain legumes to form root nodules. Inside nodules, the bacteria become bacteroids that fix nitrogen for the plant. To handle soil and host conditions, these bacteria use complex gene networks that include sRNAs.
Two computer tools, eQRNA and RNAz, scanned the S. meliloti genome for new sRNA genes in intergenic regions. Experimental validation confirmed eight new sRNA genes, each with clear promoters and terminators, producing small RNA transcripts. These loci were named smr (S. meliloti RNA). Seven of the Smr RNAs are mostly found in related Alphaproteobacteria and show different expression in free-living cells versus bacteroids.
This suggests these sRNAs act as trans-acting riboregulators, helping Alphaproteobacteria interact with plant hosts during symbiosis.
This page was last edited on 2 February 2026, at 07:17 (CET).