Abstract:
Regulation of gene expression is the fundamental aspect of biological phenomena such as responses to environmental conditions, development of multicellular
organisms, cellular differentiation, morphology and disease. Gene regulatory patterns are extraordinarily diverse, yet the regulation of each gene is very precise
both temporally as well as spatially. Gene regulation is also remarkably flexible
to accommodate rapid changes in response to new conditions and evolutionary
demands.
Molecular mechanisms underlying regulation of cellular functions were established over 50 years ago, where the central dogma of molecular biology was defined
as follows. The genetic information that is stored as DNA is transcribed into a
transient messenger RNA and it is decoded on ribosomes with the help of adapter
tRNAs to produce a functional protein. Thus, RNA was not believed to play more
than an accessory role and proteins were regarded as the ultimate functional entity of the cell. However this model is now challenged to a large extent due to
the presence of huge repertoire of RNAs that do not code for proteins and display remarkable properties more than what is known for mRNA, tRNAs or rRNAs [1].
