Temporal and spatial interaction patterns of bZIP proteins in living C. elegans

Purdue University, West Lafayette IN

Investigators

Abstract

Protein-protein interactions play a pivotal role in regulating and executing all cellular processes. Although studies of a genome-wide interaction network can provide clues to predict how each protein might function in cells through protein-protein interactions, it remains a challenge to prove whether the identified interactions are biologically relevant and how the interactions are temporally and spatially regulated in vivo. The major objective of this project is to use a novel bimolecular fluorescence complementation (BiFC) approach to investigate how protein-protein interactions are temporally and spatially regulated throughout development in the living nematode worm, C. elegans. The principle of the assay is to fuse one half of a yellow fluorescent protein (YFP) to each of two proteins and co-express them in living worms. Any interaction between the two fusion proteins brings two halves of non-fluorescent fragments in proximity and reconstitutes an intact YFP, allowing direct visualization of their interactions throughout development. Specifically, the first objective is to use Ce-FOS-1 and Ce-JUN-1, two homologs of mammalian and Drosophila Fos and Jun transcription factors which function as a heterodimer, as a model system to establish an assay for the visualization of their temporal and spatial interactions in living worms. The second objective is to identify other interaction partners of Ce-FOS-1 and examine the temporal and spatial interaction patterns of Ce-FOS-1 with other bZIP proteins (basic region leucine zipper family transcription factors). The third objective is to use RNAi and other genetic approaches to determine the loss-of-function phenotypes of these interactions and correlate the phenotypes to the temporal and spatial interaction patterns. Ultimately, the temporal and spatial interaction patterns of all bZIP proteins will be analyzed. The proven system will allow the study of temporal and spatial interactions of other families of proteins in worms and in other organisms as well. This project will involve the training of undergraduate and graduate students, and the established system will allow biology students to directly visualize how interactions of bZIP proteins regulate specific developmental events.