Abstract:

MOTIVATION: Evolutionary expansion of gene regulatory circuits seems to boost morphological complexity. However, the expansion patterns and the quantification relationships have not yet been identified. In this study, we focus on the regulatory circuits at the post-transcriptional level, investigating whether and how this principle may apply.

RESULTS: By analysing the structure of mRNA transcripts in multiple metazoan species, we observed a striking exponential correlation between the length of 3' untranslated regions (3'UTR) and morphological complexity as measured by the number of cell types in each organism. Cellular diversity was similarly associated with the accumulation of microRNA genes and their putative targets. We propose that the lengthening of 3'UTRs together with a commensurate exponential expansion in post-transcriptional regulatory circuits can contribute to the emergence of new cell types during animal evolution.

Notes:

ESI Highly Cited Paper

Notably, increasing organismal complexity correlates with lengthening of the 3' UTR (Chen et al. 2012), emphasizing the importance of this region.

—Turner et al, Nature Immuno (2014)

Other recent findings also support the view that UTRs may play a previously underappreciated role in establishing specific functions of tissues and organs: Throughout the evolution of animals, UTR length has increased along with morphological complexity (Chen et al. 2012).

—Reyes et al, Proc Natl Acad Sci USA (2013)

Chen et al. (2012) ... has reported on the exponential correlation of miRNA gene number and 3'-UTR length—but not 5'-UTR or coding sequence length—with morphological complexity in animals.

—Carroll et al, J Mol Cell Biol (2013)