4XH9: CRYSTAL STRUCTURE OF HUMAN RHOA IN COMPLEX WITH DH/PH FRAGMENT OF THE GUANINE NUCLEOTIDE EXCHANGE FACTOR NET1

Citation:
Abstract
The GTPase RhoA is a major player in many different regulatory pathways. RhoA catalyzes GTP hydrolysis, and its catalysis is accelerated when RhoA forms heterodimers with proteins of the guanine nucleotide exchange factor (GEF) family. Neuroepithelial cell transforming gene 1 (Net1) is a RhoA-interacting GEF implicated in cancer, but the structural features supporting the RhoA/Net1 interaction are unknown. Taking advantage of a simple production and purification process, here we solved the structure of a RhoA/Net1 heterodimer with X-ray crystallography at 2-A resolution. Using a panel of several techniques, including molecular dynamics simulations, we characterized the RhoA/Net1 interface. Moreover, deploying an extremely simple peptide-based scanning approach, we found that short peptides (penta- to nonapeptides) derived from the protein/protein interaction region of RhoA could disrupt the RhoA/Net1 interaction and thereby diminish the rate of nucleotide exchange. The most inhibitory peptide, EVKHF, spanning residues 102-106 in the RhoA sequence, displayed an IC50 of approximately 100 mum without further modifications. The peptides identified here could be useful in further investigations of the RhoA/Net1 interaction region. We propose that our structural and functional insights might inform chemical approaches for transforming the pentapeptide into an optimized pseudopeptide that antagonizes Net1-mediated RhoA activation with therapeutic anticancer potential.
PDB ID: 4XH9Download
MMDB ID: 126172
PDB Deposition Date: 2015/1/5
Updated in MMDB: 2018/06
Experimental Method:
x-ray diffraction
Resolution: 2  Å
Source Organism:
Similar Structures:
Biological Unit for 4XH9: dimeric; determined by author and by software (PISA)
Molecular Components in 4XH9
Label Count Molecule
Proteins (2 molecules)
1
Neuroepithelial Cell-transforming Gene 1 Protein(Gene symbol: NET1)
Molecule annotation
1
Transforming Protein Rhoa(Gene symbol: RHOA)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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