Integrative structural studies on dsRNA binding proteins

Supervisors: Atlanta Cook

Project description:

Nuclear factor 90 (NF90) and it’s binding partner NF45 form a dsRNA binding protein complex that is essential to vertebrate development and that plays a role in many aspects of RNA metabolism. This includes functions in miRNA and circRNA biogenesis and as a host factor for several viruses with RNA genomes. Understanding how NF90/NF45 recognises physiological RNAs is poorly understood and until recently few physiological partners had been validated. Recently it has been found that NF90/NF45 regulates mir7 expression by binding to precursors of mir7. Furthermore, NF90/NF45 has been found to bind specific signature sequences of pre-circRNAs and promotes formation of this class of long non-coding RNA. 

The Cook laboratory previously characterised the structured domains of NF90 and NF45 and have recently reconstituted larger complexes with pre-mir7 and circRNA sequences in vitro. This PhD project will use an integrative structural biology approach to model these structures. The student will use small angle solution scattering approaches to get molecular envelopes of the different complexes. These data will be combined with protein cross-linking and mass spectrometry approaches (in collaboration with Juri Rappsilber’s laboratory) to develop pseudo-atomic models of the RNA-bound complexes. These data will give mechanistic insights into RNA recognition in the context of medically relevant RNA metabolic pathways.