Working with the let-7 gene, the authors led by Ruvkun showed that microRNA encoded by the let-7 gene was highly conserved, and present throughout the animal kingdom, proving that gene regulation by microRNA is universal among unicellular organisms on Earth. This paper, published seven years after the initial discovery (No. 14301) provided the evidence to convince skeptics of the existence of microRNA.

Order of authorship in the original publication: Pasquinelli, Reinhart, Slack, Ruvkun.

(Thanks to Juan Weiss for this reference and its interpretation.)