Site-Directed Platinum(II) Crosslinking
We are working on developing cisplatin as a short-range, metal ion-dependent crosslinking reagent for the purpose of RNA structure determination. Cisplatin is known to form coordinate covalent bonds with guanine and adenine in both DNA and RNA. Cisplatin also binds to thiols, with 3-4 fold kinetic preference. In the DeRose Lab, we utilize nucleic acids with thiol substitutions along the phosphodiester backbone to artificially insert preferred cisplatin binding sites, and use a variety of techniques to map nearby cisplatin binding partners.
This technique has been successfully applied to the active site of the hammerhead ribozyme (Chapman and DeRose, 2010), where we found preferential targeting of  specific nucleotides near to the active site thiol substitution. These crosslinking partners agreed with the known crystal structures of the hammerhead ribozyme, and were found to be dependent on the ribozyme adopting a correctly folded structure.
Currently, we are utilizing cisplatin crossslinking to study the hepatitis delta virus (HDV) ribozyme, with the goal to better understand the structure of the HDV ribozyme active site and how a magnesium ion involved in the catalytic step is positioned.
Here are some of our current publications on this work:
Platinum-RNA Modifications Following Drug Treatment in S. cerevisiae Identified by Click Chemistry and Enzymatic Mapping
Maire F. Osborn , Jonathan D. White , Michael M. Haley , and Victoria J. DeRose ACS Chem. Biol. 2014 ASAP Link
Site-Specific Platinum(II) Cross-Linking in a Ribozyme Active Site
Chapman, Erich G.; DeRose, Victoria J. JACS 2012, 134(1), 256-262 Link
RNA-Pt Adducts Following Cisplatin Treatment of Saccharomyces cerevisiae
Hostetter, Alethia A.; Osborn, Maire F.; DeRose, Victoria J. ACS Chemical Biology 2012, 7(1), 218-225 Link
Binding of Kinetically Inert Metal Ions to RNA: the Case of Platinum(II)
Chapman, Erich G.; Hostetter, Alethia A.; Osborn, Maire F.; Miller, Amanda L.; DeRose, Victoria J. Metal Ions in Life Sciences 2011, 9(Structural and Catalytic Roles of Metal Ions in RNA), 347-377. Link
Ru binding to RNA Following Treatment with the Antimetastatic Prodrug NAMI-A in Saccharomyces Cerevisiae and In-Vitro
Hostetter, Alethia A.; Miranda, Michelle L.; DeRose, Victoria J.; McFarlane Holman, Karen L. JBIC 2011, 16(8), 1177-1185 Link
Enzymatic Processing of Platinated RNAs
Chapman, Erich G.; DeRose, Victoria J. JACS 2010, 132(6), 1946-1952. Link
Rapid Cross-Linking of an RNA Internal Loop by the Anticancer Drug Cisplatin
Hostetter, Alethia A.; Chapman, Erich G.; DeRose, Victoria J. From JACS 2009, 131(26), 9250-9257. Link