Biosciences Research Seminar - Small RNA evolution: insights from Cnidaria

Small non-coding RNAs such as microRNAs (miRNAs), small interfering RNAs and piwi-interacting RNAs regulate the levels of endogenous, viral and transposable element RNA in plants (excluding piRNAs) and animals. To obtain deeper insights into the evolution of small RNA biogenesis, one must look into a wider repertoire of extant species such as non-bilaterian animals that represent lineages that diverged more than 600 million years ago (MYA) from the rest of the Metazoa. These include the phyla Porifera (sponges), Ctenophora (comb jellies), Placozoa (Trichoplax) and Cnidaria (sea anemones, corals, hydroids and jellyfish). During my postdoctoral research at the laboratory of Assoc. Prof. Yehu Moran (The Hebrew University of Jerusalem), we explored the evolution of small RNA biogenesis in sea anemone Nematostella vectensis, a cnidarian model. This research resulted in unprecedented outcomes: 1) Developmental role of miRNAs in Nematostella was demonstrated through interfering with Drosha and Dicer components of miRNA biogenesis; this is the first evidence of the involvement of miRNAs in the development of a non-bilaterian animal. 2) Characterizing the small RNA effector components (Argonautes) revealed their putative state in the cnidarian-bilaterian ancestor. 3) Further, the high complementarity between miRNA and its mRNA targets as well as miRNA 3′ methylation by HEN1 in Nematostella, suggest that the common ancestor of plants and animals may have possessed these features. In overall, our research provided an insight into the evolution of small RNAs in Metazoans.

Brief CV:

I have always been fascinated about understanding the molecular mechanisms underlying the evolution of animals. I joined Prof Kevin Nicholas lab at the Deakin University, Australia to study the evolution of mammals and the role of maternal factors in regulating fetal development. I received my PhD in 2015 for the research on understanding the lung developmental of altricial marsupial pouch young. The study also identified significances of maternal micro-RNAs that potentially stimulate developmental processes. After my doctoral studies, I joined Assoc. Prof. Yehu Moran’s lab (July 2015), and I expanded my research interest in studying the evolution of small RNA biogenesis in Nematostella vectensis. This study resulted in exciting findings related to the evolution of small RNAs in Metazoans. In 2018, I was awarded the Anne Warner Fellowship at the Marine Biological Association in Plymouth. I wish to understand the evolution of early animal life forms at the molecular and genomic levels and its impact on current animal diversity. Currently, I am studying the function of the apical sensory organ in Cnidaria. As a part of my long term quest, I continue exploring the evolution of small RNAs biogenesis in phyla Porifera (sponges), Ctenophora (comb jellies) and Placozoa (Trichoplax).