Mechanism of RNA processing by the Dicer enzyme
EMSL Project ID
50628
Abstract
We aim to achieve an atomic-resolution understanding of how Dicer recognizes and processes its RNA substrates. We recently solved a 6.8 Å resolution cryo-EM structure of the Drosophila Dicer-2 (dmDcr-2) enzyme bound to a viral-like dsRNA substrate (Sinha et al., Science, 2018). This structure demonstrated a new mode of RNA binding by Dicers and rationalized a mechanism by which dmDcr-2 distinguishes between self and non-self RNAs.Our unexpected discovery has created new opportunities to more fully understand how Dicer works. Our published structure only showed half of the Dicer protein (~100 kDa) and was determined using modest instrumentation (TF20/K2). We have since improved our biochemical approach to trap the dmDcr-2:dsRNA complex in order to visualize the complete densities of the full-length protein. We also believe that the resolution could be greatly improved using data collected on a Titan Krios/K2. As described below, our institution currently lacks the means to perform cryo-EM. Rapid Access to PNNL will enable us to evaluate new grids so we can make progress towards achieving an enhanced mechanistic understanding of Dicer-RNA interactions. Successful evaluation of our new grids will provide us with the necessary preliminary data to apply for Standard Access at PNNL.
Project Details
Start Date
2018-12-17
End Date
2019-04-10
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)