2m3o
From Proteopedia
Structure and dynamics of a human Nedd4 WW domain-ENaC complex
Structural highlights
Disease[SCNNA_HUMAN] Idiopathic bronchiectasis;Generalized pseudohypoaldosteronism type 1. The disease is caused by mutations affecting the gene represented in this entry. The degree of channel function impairment differentially affects the renin-aldosterone system and urinary Na/K ratios, resulting in distinct genotype-phenotype relationships in PHA1 patients. Loss-of-function mutations are associated with a severe clinical course and age-dependent hyperactivation of the renin-aldosterone system. This feature is not observed in patients with missense mutations that reduce but do not eliminate channel function. Markedly reduced channel activity results in impaired linear growth and delayed puberty (PubMed:18634878). The disease is caused by mutations affecting the gene represented in this entry. Function[NEDD4_HUMAN] E3 ubiquitin-protein ligase which accepts ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates. Involved in the pathway leading to the degradation of VEGFR-2/KDFR, independently of its ubiquitin-ligase activity. Monoubiquitinates IGF1R at multiple sites, thus leading to receptor internalization and degradation in lysosomes. Ubiquitinates FGFR1, leading to receptor internalization and degradation in lysosomes. According to PubMed:18562292 the direct link between NEDD4 and PTEN regulation through polyubiquitination described in PubMed:17218260 is questionable. Involved in ubiquitination of ERBB4 intracellular domain E4ICD. Involved in the budding of many viruses. Part of a signaling complex composed of NEDD4, RAP2A and TNIK which regulates neuronal dendrite extension and arborization during development. Ubiquitinates TNK2 and regulates EGF-induced degradation of EGFR and TNF2.[1] [2] [3] [4] [5] [SCNNA_HUMAN] Sodium permeable non-voltage-sensitive ion channel inhibited by the diuretic amiloride. Mediates the electrodiffusion of the luminal sodium (and water, which follows osmotically) through the apical membrane of epithelial cells. Controls the reabsorption of sodium in kidney, colon, lung and sweat glands. Also plays a role in taste perception. Publication Abstract from PubMedNedd4-1 (neuronal precursor cell expressed developmentally downregulated gene 4-1) is an E3 ubiquitin ligase that interacts with and negatively regulates the epithelial Na(+) channel (ENaC). The WW domains of Nedd4-1 bind to the ENaC subunits via recognition of PY motifs. Human Nedd4-1 (hNedd4-1) contains four WW domains with the third domain (WW3*) showing the strongest affinity to the PY motif. To understand the mechanism underlying this binding affinity, we have carried out NMR structural and dynamics analyses of the hNedd4-1 WW3* domain in complex with a peptide comprising the C-terminal tail of the human ENaC alpha-subunit. The structure reveals that the peptide interacts in a similar manner to other WW domain-ENaC peptide structures. Crucial interactions that likely provide binding affinity are the broad XP groove facilitating additional contacts between the WW3* domain and the peptide, compared to similar complexes, and the large surface area buried (83A(2)) between R430 (WW3*) and L647' (alphaENaC). This corroborates the model-free analysis of the (15)N backbone relaxation data, which showed that R430 is the most rigid residue in the domain (S(2)=0.90+/-0.01). Carr-Purcell-Meiboom-Gill relaxation dispersion analysis identified two different conformational exchange processes on the mus-ms time-scale. One of these processes involves residues located at the peptide binding interface, suggesting conformational exchange may play a role in peptide recognition. Thus, both structural and dynamic features of the complex appear to define the high binding affinity. The results should aid interpretation of biochemical data and modeling interfaces between Nedd4-1 and other interacting proteins. Structure and dynamics of human Nedd4-1 WW3 in complex with the alphaENaC PY motif.,Bobby R, Medini K, Neudecker P, Lee TV, Brimble MA, McDonald FJ, Lott JS, Dingley AJ Biochim Biophys Acta. 2013 Aug;1834(8):1632-41. doi:, 10.1016/j.bbapap.2013.04.031. Epub 2013 May 8. PMID:23665454[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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