Solution Structure of the Calcium Binding Domain of the C-terminal Cytosolic Domain of Polycystin-2
[PKD2_HUMAN] Defects in PKD2 are the cause of polycystic kidney disease 2 (PKD2) [MIM:613095]. PKD2 is a disorder characterized by progressive formation and enlargement of cysts in both kidneys, typically leading to end-stage renal disease in adult life. Cysts also occurs in the liver and other organs. It represents approximately 15% of the cases of autosomal dominant polycystic kidney disease. PKD2 is clinically milder than PKD1 but it has a deleterious impact on overall life expectancy.        
[PKD2_HUMAN] Involved in fluid-flow mechanosensation by the primary cilium in renal epithelium (By similarity). PKD1 and PKD2 may function through a common signaling pathway that is necessary for normal tubulogenesis (By similarity). Acts as a regulator of cilium length, together with PKD1 (By similarity). The dynamic control of cilium length is essential in the regulation of mechanotransductive signaling. The cilium length response creates a negative feedback loop whereby fluid shear-mediated deflection of the primary cilium, which decreases intracellular cAMP, leads to cilium shortening and thus decreases flow-induced signaling (By similarity). Functions as a calcium permeable cation channel.
Publication Abstract from PubMed
Mutations in the PKD2 gene lead to the development of polycystic kidney disease (PKD). The PKD2 gene codes for polycystin-2, a cation channel with unknown function. The cytoplasmic, C-terminal domain interacts with a large number of proteins including mDia1, alpha-actinin, PIGEA-14, troponin, and tropomyosin. The C-terminal fragment polycystin-2 (680-796) consisting of 117 amino acids contains a putative calcium binding EF-hand. It was produced in Escherichia coli and enriched uniformly with (13)C and (15)N. The backbone and side chain resonances were assigned by multidimensional NMR methods, the obtained chemical shifts are typical for a partially folded protein. The chemical shifts obtained are in line with the existence of two paired helix-loop-helix (HLH) motifs.
NMR-assignments of a cytosolic domain of the C-terminus of polycystin-2.,Schumann FH, Hoffmeister H, Schmidt M, Bader R, Besl E, Witzgall R, Kalbitzer HR Biomol NMR Assign. 2009 Jun;3(1):141-4. Epub 2009 Apr 10. PMID:19636966
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.