fig5

Figure 5. Schematic illustration of the functional mechanism of decoy lncRNAs. LncRNAs are shown in blue, target mRNA/molecules in black, miRNA in purple, and genes/proteins in green. (A) LncRNAs can act as molecular decoys for proteins, such as those involved in transcription, by binding the protein and stopping binding to their target molecule, e.g., chromatin. This stops any effects that are a result of the protein binding to its target. Without lncRNA presence, e.g., through knockout, there is an increase in circulating protein, so it can bind its target and produce the intended effects. (B) Here, lncRNAs act as competing endogenous RNAs to bind and sequester miRNAs, making them unable to bind to their target mRNA. Typically, miRNAs inhibit their target mRNA sequence, so this sequestering results in an increase in the expression of their target mRNA^[103]. In the absence of lncRNAs, e.g., through knockout, miRNAs are free to bind to their target mRNAs, inhibiting their expression.