2FPE

Conserved dimerization of the ib1 src-homology 3 domain

DOI: 10.2210/pdb2FPE/pdb

Classification: SIGNALING PROTEIN
Organism(s): Rattus norvegicus
Expression System: Escherichia coli
Mutation(s): No

Deposited: 2006-01-16 Released: 2006-02-28
Deposition Author(s): Guenat, S., Dar, I., Bonny, C., Kastrup, J.S., Gajhede, M., Kristensen, O.

Experimental Data Snapshot

Method: X-RAY DIFFRACTION
Resolution: 1.75 Å
R-Value Free: 0.235
R-Value Work: 0.204
R-Value Observed: 0.204

wwPDB Validation3D Report Full Report

This is version 1.3 of the entry. See complete history.

Literature

A unique set of SH3-SH3 interactions controls IB1 homodimerization

Kristensen, O., Guenat, S., Dar, I., Allaman-Pillet, N., Abderrahmani, A., Ferdaoussi, M., Roduit, R., Maurer, F., Beckmann, J.S., Kastrup, J.S., Gajhede, M., Bonny, C.

(2006) EMBO J 25: 785-797

PubMed: 16456539 Search on PubMedSearch on PubMed Central
DOI: 10.1038/sj.emboj.7600982
Structures With Same Primary Citation

PubMed Abstract:

Islet-brain 1 (IB1 or JIP-1) is a scaffold protein that interacts with components of the c-Jun N-terminal kinase (JNK) signal-transduction pathway. IB1 is expressed at high levels in neurons and in pancreatic beta-cells, where it controls expression of several insulin-secretory components and secretion. IB1 has been shown to homodimerize, but neither the molecular mechanisms nor the function of dimerization have yet been characterized. Here, we show that IB1 homodimerizes through a novel and unique set of Src homology 3 (SH3)-SH3 interactions. X-ray crystallography studies show that the dimer interface covers a region usually engaged in PxxP-mediated ligand recognition, even though the IB1 SH3 domain lacks this motif. The highly stable IB1 homodimer can be significantly destabilized in vitro by three individual point mutations directed against key residues involved in dimerization. Each mutation reduces IB1-dependent basal JNK activity in 293T cells. Impaired dimerization also results in a reduction in glucose transporter type 2 expression and in glucose-dependent insulin secretion in pancreatic beta-cells. Taken together, these results indicate that IB1 homodimerization through its SH3 domain has pleiotropic effects including regulation of the insulin secretion process.

Related Citations:

A cytoplasmic inhibitor of the JNK signal transduction pathway
Dickens, M., Rogers, J.S., Cavanagh, J., Raitano, A., Xia, Z., Halpern, J.R., Greenberg, M.E., Sawyers, C.L., Davis, R.J.
(1997) Science 277: 693

IB1, a JIP-1-related nuclear protein present in insulin-secreting cells
Bonny, C., Nicod, P., Waeber, G.
(1998) J Biol Chem 273: 1843

Recruitment of JNK to JIP1 and JNK-dependent JIP1 phosphorylation regulates JNK module dynamics and activation
Nihalani, D., Wong, H.N., Holzman, L.B.
(2003) J Biol Chem 278: 28694

The JIP group of mitogen-activated protein kinase scaffold proteins
Yasuda, J., Whitmarsh, A.J., Cavanagh, J., Sharma, M., Davis, R.J.
(1999) Mol Cell Biol 19: 7245

Organizational Affiliation:

Biostructural Research, Department of Medicinal Chemistry, The Danish University of Pharmaceutical Sciences, Copenhagen, Denmark. ok@dfuni.dk

Macromolecules

Find similar proteins by: Sequence | Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
C-jun-amino-terminal kinase interacting protein 1	A, B, C, D, E, F, G, H	62	Rattus norvegicus	Mutation(s): 0 Gene Names: Mapk8ip1, Ib1, Jip1, Mapk8ip
Find proteins for Q9R237 (Rattus norvegicus) Go to UniProtKB: Q9R237
Protein Feature View Full Protein Feature View for Q9R237

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram	3D Interactions
P6G Query on P6G Download CCD File	A, D, G	HEXAETHYLENE GLYCOL C₁₂ H₂₆ O₇ IIRDTKBZINWQAW-UHFFFAOYSA-N		Ligand Interaction
SO4 Query on SO4 Download CCD File	A, B, C, E, H	SULFATE ION O₄ S QAOWNCQODCNURD-UHFFFAOYSA-L		Ligand Interaction
SO2 Query on SO2 Download CCD File	F	SULFUR DIOXIDE O₂ S RAHZWNYVWXNFOC-UHFFFAOYSA-N		Ligand Interaction