terC motif RNAs likely function as cis-regulatory elements, in view of their positions upstream of protein-coding genes.

If all examples of the RNA were upstream of homologous genes, there is the possibility that the RNAs were conserved in that position simply by inheritance.

[2] A separate conserved RNA, originally known as the YybP-ykoY leader, is now known to function as a manganese-sensing riboswitch.

Genes regulated by these manganese riboswitches very frequently encode proteins similar to TerC.

In view of this association, it was proposed[1] that terC RNAs might also function as riboswitches that sense an ion similar to manganese.