CSB Departmental Seminar: “Trans-species microRNAs from the parasitic plant Cuscuta target host mRNAs”

Professor Michael Axtell
The Pennsylvania State University

“Trans-species microRNAs from the parasitic plant Cuscuta target host mRNAs”

Abstract:

MicroRNAs are short non-coding RNAs that function to negatively regulate longer target RNAs. They are well known as important regulators of numerous gene expression modules in plants, animals, and humans. Parasitic plants are widespread in nature and can cause significant crop losses. One widespread genus of parasitic plants is Cuscuta, which has around 200 species that are collectively found world-wide. Cuscuta plants are yellow vines that lack roots and attach to the stems or petioles of host plants. We have discovered that Cuscuta has a set of more than 50 microRNAs that only accumulate at the interface between parasite and host. These microRNAs can target certain host mRNAs for degradation; thus we call them trans-species microRNAs. Targets of trans-species microRNAs are often involved in pathogen defense responses, hormone signaling, or vascular system functions. Our hypothesis is that Cuscuta trans-species microRNAs function to remodel host gene expression in order to promote Cuscuta fitness. In my talk I will describe our recent results, including a unique mode of molecular evolution for Cuscuta trans-species microRNAs, and progress towards understanding the transcriptional control of the trans-species microRNAs.

Host: Shelley Lumba: shelley.lumba@utoronto.ca