Discovery and Testing of Ricin Therapeutics
Abstract
Ricin is an extremely potent A-B toxin that is transported from the cell surface to the cytosol where it inactivates ribosomes leading to cell death. Ricin access to the cytosol is dependent on its transport from the cell surface to the ER lumen. An elegant human cell system that specifically examines ricin A chain dislocation across the ER bilayer has been established. Using enzymatic attenuated ricin A chain molecules (RTAE177D and RTA!), ricin A chains undergo a rapid transport across the ER membrane and into cytosol where it is eventually degraded by the proteasome. The transport of the ricin A chain occurred via a membrane associated intermediate and likely utilizes some components of ER quality control. These assays demonstrate that ricin A chain is an unstable molecule whose instability will be utilized in a high-thoughput screen to identify chemicals that block ricin transport, thus stabilizing the ricin molecule. A green fluorescent protein ricin chimeras that allow for more efficient screening have been generated and optimized to create a very roust high-throughput screen. These cells expressing the fluorescent ricin molecule will be utilized to discover novel inhibitors that block ricin intoxication.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2011
- Accession Number
- ADA547965
Entities
People
- Domenico Tortorella
Organizations
- Icahn School of Medicine at Mount Sinai