We established that fact in our 1996 Hormones and Behavior review of RNA-mediated cell type differentiation at a time when microRNAs were called pre-mRNAs. See our molecular epigenetics section: http://www.hawaii.edu/PCSS/biblio/articles/1961to1999/1996-from-fertilization.html
Since then, these are some of the Nobel Laureates who have extended what is known about RNA-mediated cause and effect to what is known about all food energy-dependent pheromone-controlled biodiversity.
2004 Richard Axel (US) and Linda Buck (US) for their discoveries of “odorant receptors and the organization of the olfactory system.
2016: Yoshinori Ohsumi of Japan for his work on autophagy—a process whereby cells “eat themselves”—which when disrupted can cause Parkinson’s and diabetes.
2017: US geneticists Jeffrey Hall, Michael Rosbash and Michael Young for their discoveries on the internal biological clock that governs the wake-sleep cycles of most living things.
Nothing that happens in the life of any organism happens outside the context of the food energy-dependent biophysically constrained creation of ATP and RNA. All serious scientists know that, and their works have placed the facts about cell type differentiation into the context of feedback loops and messenger RNA cycling since 1990. See: Feedback of the Drosophila period gene product on circadian cycling of its messenger RNA levels https://www.nature.com/articles/343536a0
Each time you see a report that indicates something new about energy-dependent feedback loops has been discovered, ask what the authors are trying to do. Keep this in mind, so that you know the answer:
“Nobody wants to belong to the party of losers. One of the best strategies in such a case is evidently an interpretation of the change as a gradual accumulation of knowledge while their work has always been at the cutting edge.” — Kalevi Kull http://www.huffingtonpost.com/suzan-mazur/kalevi-kull-censorship–r_b_10797646.html