Disordered Motifs and Domains in Cell Control - October 11-15, 2014

Disordered Motifs and Domains in Cell Control

Poster Session I

14-POS Board 14 The STIL Protein Contains Intrinsically Disordered Regions that Mediate its Protein- protein Interactions Hadar Amartely , Assaf Friedler. Institute of Chemistry, The Hebrew University, Jerusalem, Israel. STIL is a centrosomal protein that participates in centrosomal biogenesis and controls normal cell division. Its expression is crucial for the development of tissues, especially embryonic. Overexpression of STIL is correlated with formation of numerous types of cancer. Despite its importance, the mechanism of action of STIL is not clear and no structural or quantitative information is available about the protein. Here we performed structural and biophysical characterization of the central domain of STIL. We divided the protein to several fragments and developed, for the first time, protocols for expression and purification of the recombinant central domains of STIL: STIL4 200-450, STIL5 450-700 and STIL6 500-650. SEC, CD and computational disorder predictions revealed that the central domain of STIL is mostly disordered. This region mediates the interactions of STIL with the CHFR protein: Peptide array screening and fluorescence anisotropy revealed CHFR-derived peptides that bound STIL IDR with nanomolar affinity. The intrinsic disorder may provide STIL the flexibility required for its function. The structural properties of STIL combined with the large number of interactions with its different partners make STIL likely to be a scaffold protein.

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