Individual miRNAs can modulate multiple mRNA targets, and individual mRNAs can be regulated by multiple, distinct miRNAs [ 20].
As each miRNA can recognize many hundreds of targets, and multiple miRNAs may target individual mRNAs, these gene regulatory networks can become rather complex.
Individual miRNA may target multiple mRNAs, and individual mRNA may contain sequences complementary to multiple miRNA family members [ 13, 14].
These studies revealed that individual mRNAs bind multiple SR proteins, as was also described in insect cells (Björk et al., 2009).
Moreover, the small amount of miRNAs is able to regulate a large number of genes through synergism, in which multiple miRNAs work synergistically to regulate individual mRNAs [ 9- 11].
The versatility of miRNA-mediated gene regulation is evidenced by the finding that individual miRNAs can target hundreds of genes while individual mRNAs can be targeted by multiple miRNAs, allowing for enormous complexity and flexibility in their regulatory potential [28].
As individual mRNAs are often regulated by multiple miRNAs, this most likely explains the lack of de-repression with the miR-5364 ASO.
Conversely, individual mRNAs may contain sequences complementary to multiple miRNA family members [3], [4].
Previous studies indicated that an individual miRNA could affect expression of multiple genes and an individual mRNA might also be regulated by multiple miRNAs, which was mainly through miRNA targeting 3′ untranslated region (3′-UTR) of mRNA [ 38].
Coinjection of the four individual mRNAs did not cause any apparent lethality, so coexpressing multiple TALEN pairs could be an effective method for simultaneously generating mutants in several targets.
