PDBsum entry 3jxj

Membrane protein

PDB id: 3jxj

Contents

Protein chains

257 a.a. *

Ligands

PO4 ×2

* Residue conservation analysis

PDB id:

3jxj

Name:

Membrane protein

Title:

Crystal structure of the chicken trpv4 ankyrin repeat domain

Structure:

Vanilloid receptor-related osmotically activated channel protein. Chain: a, b. Fragment: unp residues 133-382, ankyrin repeat domain. Engineered: yes

Source:

Gallus gallus. Chicken. Organism_taxid: 9031. Gene: trpv4, vr-oac. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.80Å R-factor: 0.264 R-free: 0.298

Authors:

C.B.Phelps,S.S.Choo,R.Gaudet

Key ref:

G.Landouré et al. (2010). Mutations in TRPV4 cause Charcot-Marie-Tooth disease type 2C. Nat Genet, 42, 170-174. PubMed id: 20037586 DOI: 10.1038/ng.512

Date:

19-Sep-09 Release date: 22-Dec-09

Protein chains

A0A1D5PXA5  (TRPV4_CHICK) -  Transient receptor potential cation channel subfamily V member 4 from Gallus gallus

Seq: 852 a.a.

Struc: 257 a.a.*

* PDB and UniProt seqs differ at 6 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1038/ng.512

Nat Genet 42:170-174 (2010)

PubMed id: 20037586

Mutations in TRPV4 cause Charcot-Marie-Tooth disease type 2C.

G.Landouré, A.A.Zdebik, T.L.Martinez, B.G.Burnett, H.C.Stanescu, H.Inada, Y.Shi, A.A.Taye, L.Kong, C.H.Munns, S.S.Choo, C.B.Phelps, R.Paudel, H.Houlden, C.L.Ludlow, M.J.Caterina, R.Gaudet, R.Kleta, K.H.Fischbeck, C.J.Sumner.

ABSTRACT

Charcot-Marie-Tooth disease type 2C (CMT2C) is an autosomal dominant neuropathy characterized by limb, diaphragm and laryngeal muscle weakness. Two unrelated families with CMT2C showed significant linkage to chromosome 12q24.11. We sequenced all genes in this region and identified two heterozygous missense mutations in the TRPV4 gene, C805T and G806A, resulting in the amino acid substitutions R269C and R269H. TRPV4 is a well-known member of the TRP superfamily of cation channels. In TRPV4-transfected cells, the CMT2C mutations caused marked cellular toxicity and increased constitutive and activated channel currents. Mutations in TRPV4 were previously associated with skeletal dysplasias. Our findings indicate that TRPV4 mutations can also cause a degenerative disorder of the peripheral nerves. The CMT2C-associated mutations lie in a distinct region of the TRPV4 ankyrin repeats, suggesting that this phenotypic variability may be due to differential effects on regulatory protein-protein interactions.

Selected figure(s)

Figure 2.
(a) Quantification of TRPV4 transcript by qRT-PCR in control human lymphoblast lines (n = 4), human dorsal spinal cord (n = 3), ventral spinal cord (n = 3) and tracheal cartilage (n = 3) using primers specific for the following exon regions: exons 3–4, exons 5–6, exons 7–8, exon 5 and exon 7. Values are normalized to the first tracheal cartilage sample. Data is averaged; error bars, s.e.m. (b) DRG neurons were transfected with wild-type and mutant forms of TRPV4 (green). At 16 h, some cells expressing mutant forms of TRPV4 show evidence of early cellular toxicity with a collapsed cytoplasm. The nuclear DAPI stain is blue. Scale bar, 40 μm. (c) Quantification of propidium iodide uptake in DRG neurons expressing wild-type and mutant TRPV4 reveals a marked increase of cell toxicity in mutant expressing cells at 48 h. *P < 0.0001. (d) HEK293 cells expressing R269C and R269H mutants show an increase in the number of dead cells (red channel is EthD-1 stain) at 48 h; this increase is prevented by the TRP channel blocker ruthenium red (RR). Green channel is calcein-AM stain for live cells. Scale bar, 200 μm. (e) Quantification of cell death in HEK293 cells indicates a time-dependent increase in cell death that is blocked by the TRP channel blocker ruthenium red (RR). *P < 0.01, **P < 0.001. Data in c and e are averaged from three independent experiments; error bars, s.e.m.

Figure 4.
(a) Primary structure of the TRPV4 protein, with the positions of the CMT2C-associated (Arg269; blue arrowhead) and skeletal dysplasia–associated^6, ^7 (green arrowheads) mutations indicated below. (b) Ribbon diagram of the chicken Trpv4 ARD, with the location of the Arg269 residue (Arg255 in chicken sequence) depicted as a blue sphere and the Ile331 and Asp333 residues (Ile317 and Asp319 in chicken sequence, respectively) previously shown to be mutated in skeletal dysplasia as green spheres. (c) Surface representation of the TRPV4 ARD with Arg269 in blue and Ile331 and Asp333 in green. Residues that differ between chicken and human TRPV4 are yellow, demonstrating that the palm and finger regions are conserved.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nat Genet (2010, 42, 170-174) copyright 2010.

Figures were selected by an automated process.