sentences:  The specific functions of these proteins are unknown, but this structured RNA element may be involved in their genetic regulation as a riboswitch.The "yybP-ykoY" element was later proposed to be manganese-responsive after another associated family of genes, "YebN/MntP", was shown to encode Mn2+ efflux pumps in several bacteria.Genetic data and a crystal structure confirmed that "yybp-ykoY" is a manganese riboswitch that directly binds Mn2+