| Structural highlights
Function
[TRPV5_RABIT] Constitutively active calcium selective cation channel thought to be involved in Ca(2+) reabsorption in kidney and intestine (PubMed:12574114). Required for normal Ca(2+) reabsorption in the kidney distal convoluted tubules (By similarity). The channel is activated by low internal calcium level and the current exhibits an inward rectification (By similarity). A Ca(2+)-dependent feedback regulation includes fast channel inactivation and slow current decay (By similarity). Heteromeric assembly with TRPV6 seems to modify channel properties. TRPV5-TRPV6 heteromultimeric concatemers exhibit voltage-dependent gating (PubMed:12574114).[UniProtKB:P69744][UniProtKB:Q9NQA5][1] [2] [3] [CALM_BOVIN] Calmodulin mediates the control of a large number of enzymes, ion channels and other proteins by Ca(2+). Among the enzymes to be stimulated by the calmodulin-Ca(2+) complex are a number of protein kinases and phosphatases. Together with CEP110 and centrin, is involved in a genetic pathway that regulates the centrosome cycle and progression through cytokinesis (By similarity).
Publication Abstract from PubMed
TRPV5 (transient receptor potential vanilloid 5) is a unique calcium-selective TRP channel essential for calcium homeostasis. Unlike other TRPV channels, TRPV5 and its close homolog, TRPV6, do not exhibit thermosensitivity or ligand-dependent activation but are constitutively open at physiological membrane potentials and modulated by calmodulin (CaM) in a calcium-dependent manner. Here we report high-resolution electron cryomicroscopy structures of truncated and full-length TRPV5 in lipid nanodiscs, as well as of a TRPV5 W583A mutant and TRPV5 in complex with CaM. These structures highlight the mechanism of calcium regulation and reveal a flexible stoichiometry of CaM binding to TRPV5.
Structural insight into TRPV5 channel function and modulation.,Dang S, van Goor MK, Asarnow D, Wang Y, Julius D, Cheng Y, van der Wijst J Proc Natl Acad Sci U S A. 2019 Apr 11. pii: 1820323116. doi:, 10.1073/pnas.1820323116. PMID:30975749[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Hoenderop JG, van der Kemp AW, Hartog A, van de Graaf SF, van Os CH, Willems PH, Bindels RJ. Molecular identification of the apical Ca2+ channel in 1, 25-dihydroxyvitamin D3-responsive epithelia. J Biol Chem. 1999 Mar 26;274(13):8375-8. PMID:10085067
- ↑ Nilius B, Vennekens R, Prenen J, Hoenderop JG, Droogmans G, Bindels RJ. The single pore residue Asp542 determines Ca2+ permeation and Mg2+ block of the epithelial Ca2+ channel. J Biol Chem. 2001 Jan 12;276(2):1020-5. PMID:11035011 doi:http://dx.doi.org/10.1074/jbc.M006184200
- ↑ Hoenderop JG, Voets T, Hoefs S, Weidema F, Prenen J, Nilius B, Bindels RJ. Homo- and heterotetrameric architecture of the epithelial Ca2+ channels TRPV5 and TRPV6. EMBO J. 2003 Feb 17;22(4):776-85. PMID:12574114 doi:http://dx.doi.org/10.1093/emboj/cdg080
- ↑ Dang S, van Goor MK, Asarnow D, Wang Y, Julius D, Cheng Y, van der Wijst J. Structural insight into TRPV5 channel function and modulation. Proc Natl Acad Sci U S A. 2019 Apr 11. pii: 1820323116. doi:, 10.1073/pnas.1820323116. PMID:30975749 doi:http://dx.doi.org/10.1073/pnas.1820323116
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