Christian Zwieb, PhD, Professor/Research
I study translational ribonucleoprotein particles (RNPs). Methods for determining RNP structure and function include comparative sequence analyses (see rnp.uthscsa.edu ), cloning and purification of the constituents, reconstitution of recombinant RNPs, site-directed mutagenesis, crosslinking, molecular modeling, as well as collaborative biophysical methods such as X-ray crystallography, NMR, and cryo-EM.
SRP: Proteins SRP68 and SRP72 bind to each other and to the SRP RNA. We want to understand these interactions and their implications for SRP assembly, structure, and function. The SRP54 protein and the SRP RNA are in close proximity to the signal peptide, but how recognition occurs on the molecular level is unknown. Our goal is to trap the transiently-bound signal peptide and determine the structure of the complex. These studies are carried out in collaboration with Dr. Andy Hinck, University of Texas, Health Science Center San Antonio, Texas, U.S.A.
tmRNP: We use comparative sequence analyses to determine the structures of all tmRNAs across the phylogenetic spectrum in order to understand which regions are imporant and which may be species specific. (2) The tmRNA binds to SmpB and ribosomal protein S1 and changes its shape when bound to the ribosome. Our goal is to determine the structural differences between the varied functional stages of the E. coli tmRNP. (3) Certain tmRNP regions are redundant and others are essential for function. We determine the relative importance of each region in vitro and in vivo. These studies are carried out in collaboration with Dr. Jacek Wower, University of Auburn, Auburn, Alabama, U.S.A., as the Principal Investigator.
RNP databases: We develop tools to identify RNA genes and to generate and visualize RNA and protein alignments. Our focus is on SRPDB and tmRDB but we aim to expand into other RNPs. This work is carried out in collaboration with investigators in Denmark and Sweden. (See Nucleic Acids Res. (2006) 34:D163-D168)
RNA Sensors & Drug Delivery: We exploit the potential of RNA to sense a wide variety of targets. Long RNA chains designed to form RNA networks with hydrogel-like properties are synthesized and combined to achieve a multitude of detection and drug delivery needs.
Complete Publication Listing