Definition of Protein Networks using RNA Display
Principal Investigator: Jack W. Szostak
The individual steps in signal transduction pathways involve
protein interactions with target molecules that may be other proteins,
small molecules or DNA. Identifying all of the proteins that take part
in a given class of interactions, on a genome-wide scale, remains an extremely
challenging task. We propose to apply mRNA display (1,
2) technology to this problem, with the goal of developing
databases of protein-ligand interactions that will add value to the existing
and growing sequence databases. In mRNA display, proteins or peptides
are covalently linked to their own mRNA; enrichment of a protein or peptide
on the basis of an interaction such as binding to a target protein or
ligand allows ready identification of the enriched protein on the basis
of its attached mRNA, e.g. by sequencing or DNA microarray readout. The
technology is well-suited to genomic screening for functional interactions,
because complex mRNA-display libraries representing all proteins and protein
domains can easily be generated. We propose to initially apply this approach
to a class of signaling interactions that are important to the tissue
and disease states that are the subject of this proposal - PDZ-domain::peptide
interactions. These and subsequent experiments aimed at other classes
of interactions will generate large networks of protein::protein interactions,
and may lead to the identification of previously unknown signaling molecules
that play important roles in mediating disease states.
- To create a cellular protein-RNA fusion library from
pooled mRNA from normal human and mouse tissues
- To use isolated domains from proteins transducing stress
and inflammation pathway signals to identify interaction partners of
- To automate the detection of interactions between signal
transduction proteins and their target proteins.
- Roberts, R. W., and J. W. Szostak.
1997. RNA-peptide fusions for the in vitro selection of peptides and
proteins. Proc Natl Acad Sci U S A 94:12297-302.
- Liu R, B. J., Szostak JW, Roberts
RW. 2000. Optimized synthesis of RNA-protein fusions for in vitro protein
selection. Methods in Enzymol. in press.
To learn more abou the Definition of Protein Networks using RNA
Display project, visit the
Lab Web Site.