The Science of Existence (135-3-1) microRNA


microRNA (miRNA) are a diverse class of short noncoding regulatory RNA molecules that inhibit expression by binding to microRNA response elements (MREs), thereby decreasing the stability of messenger RNA (mRNA) or limiting the efficacy of protein translation.

microRNAs work in middle management: regulating protein manufacture. They help a cell maintain balance by not making unnecessary proteins and help prevent build-up of potentially harmful proteins.

An evolutionarily ancient avenue of genetic regulation, microRNA pathways are well conserved in eukaryotes.

The repertoires of plant and animal microRNAs evolved independently, with different ways of working. Animal microRNAs are specific in the binding, while plant microRNAs may bind at both coding and noncoding regions.

microRNA offers combinatorial regulation. A microRNA may have different mRNA targets, and any given site subject to regulation may be targeted by multiple microRNAs.

Modest alterations by microRNAs can have a butterfly effect, including changing the appearance of an organism.

microRNA activity is essential to learning. Associative memories which impart survival skills can be epigenetically passed on to offspring. microRNA is the likely physical mechanism for inheriting primal memories.

(A physical molecule cannot encapsulate a meaningful memory, but its hd energy gyre can. Many mental attributes, such as memory and stress, have physical counterparts. Here is an instance.)

microRNA plays a role in numerous diseases, including cancer. Some protect against cancer, while others promote it.

Other RNAs may compete in binding to microRNAs. By this, MREs mediate relevant communication, allowing different types of RNA to converse and build regulatory networks which act epigenetically.