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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