cis-acting as rnas are transcribed from the opposite strand of the target gene at the target gene locus. they often show high degree or complete complementarity with the target gene. if the cis-acting asrna regulates gene expression by targeting mrna, it can only target individual mrna. upon interactions with the targeting mrnas, cis-acting asrnas can either block ribosome binding or recruit rnaase to degrade the targeting mrnas rendered photorealistic in 4k