2015
Hepatocystin is Essential for TRPM7 Function During Early Embryogenesis
Overton JD, Komiya Y, Mezzacappa C, Nama K, Cai N, Lou L, Fedeles SV, Habas R, Runnels LW. Hepatocystin is Essential for TRPM7 Function During Early Embryogenesis. Scientific Reports 2015, 5: 18395. PMID: 26671672, PMCID: PMC4680877, DOI: 10.1038/srep18395.Peer-Reviewed Original ResearchConceptsXenopus laevis embryosEmbryonic lethalityTRPM7 functionLaevis embryosProtein kinase C substrate 80KEarly embryonic lethalityNoncatalytic beta subunitXenopus laevis embryogenesisEmbryonic day E11.5TRPM7 ion channelVertebrate gastrulationGastrulation defectsResident enzymesEarly embryogenesisPolycystin-2TRPM7 protein expressionDay E11.5KDa proteinGlucosidase IIEndoplasmic reticulumBeta subunitOverexpression of TRPM7Second alleleSomatic lossIon channelsSec63 and Xbp1 regulate IRE1α activity and polycystic disease severity
Fedeles SV, So JS, Shrikhande A, Lee SH, Gallagher AR, Barkauskas CE, Somlo S, Lee AH. Sec63 and Xbp1 regulate IRE1α activity and polycystic disease severity. Journal Of Clinical Investigation 2015, 125: 1955-1967. PMID: 25844898, PMCID: PMC4463201, DOI: 10.1172/jci78863.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsCell LineDisease Models, AnimalDNA HelicasesDNA-Binding ProteinsEndoribonucleasesFemaleGlucosidasesIntracellular Signaling Peptides and ProteinsKidneyMaleMiceMice, Inbred C57BLMice, KnockoutMice, TransgenicMolecular ChaperonesPolycystic Kidney, Autosomal DominantPolycystic Kidney, Autosomal RecessiveProtein Serine-Threonine KinasesProtein Structure, TertiaryReceptors, G-Protein-CoupledRecombinant Fusion ProteinsRegulatory Factor X Transcription FactorsRNA SplicingRNA, Small InterferingRNA-Binding ProteinsTranscription FactorsTransfectionTRPP Cation ChannelsUnfolded Protein ResponseX-Box Binding Protein 1ConceptsG protein-coupled receptor proteolysis siteCyst formationPolycystic liver diseaseGPS cleavagePolycystin-1IRE1α-XBP1 branchMurine genetic modelsPolycystic kidney phenotypeLiver diseasePolycystic diseaseCystic diseaseDisease manifestationsMurine modelDisease severityKidney phenotypeXBP1 activationUnfolded protein response pathwayDiseaseXBP1 overexpressionPC1 functionsProtein response pathwayEnforced expressionMiceXBP1Activation of XBP1
2014
Altered trafficking and stability of polycystins underlie polycystic kidney disease
Cai Y, Fedeles SV, Dong K, Anyatonwu G, Onoe T, Mitobe M, Gao JD, Okuhara D, Tian X, Gallagher AR, Tang Z, Xie X, Lalioti MD, Lee AH, Ehrlich BE, Somlo S. Altered trafficking and stability of polycystins underlie polycystic kidney disease. Journal Of Clinical Investigation 2014, 124: 5129-5144. PMID: 25365220, PMCID: PMC4348948, DOI: 10.1172/jci67273.Peer-Reviewed Original ResearchConceptsG-protein-coupled receptor proteolytic sitePolycystic kidney diseaseKidney diseaseGPS cleavageAutosomal dominant polycystic kidney diseaseMissense mutationsDominant polycystic kidney diseasePolycystin-1Polycystin-2Murine modelSevere formPathogenic missense mutationsPKD1 mutationsCOOH-terminal fragmentDiseaseMissense variantsExpression levelsFunctional assaysCell-based systemsAltered traffickingN-Glycosylation Determines the Abundance of the Transient Receptor Potential Channel TRPP2*
Hofherr A, Wagner C, Fedeles S, Somlo S, Köttgen M. N-Glycosylation Determines the Abundance of the Transient Receptor Potential Channel TRPP2*. Journal Of Biological Chemistry 2014, 289: 14854-14867. PMID: 24719335, PMCID: PMC4031537, DOI: 10.1074/jbc.m114.562264.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAsparagineBinding SitesBlotting, WesternCell LineCells, CulturedGlucosidasesGlycosylationHEK293 CellsHeLa CellsHumansIntracellular Signaling Peptides and ProteinsLysosomesMass SpectrometryMiceMice, KnockoutMicroscopy, FluorescenceMutationPolycystic Kidney, Autosomal DominantProtein Serine-Threonine KinasesProteolysisPyruvate Dehydrogenase Acetyl-Transferring KinaseConceptsGlucosidase IINon-catalytic β-subunitsProtein expressionFirst extracellular loopAutosomal dominant polycystic liver diseaseEfficient biogenesisGenetic interactionsMembrane proteinsBiochemical approachesN-glycosylationGenetic approachesTRPP2Glycosylation sitesBiological roleLysosomal degradationΒ-subunitChemical inhibitionBiogenesisExtracellular loopNonselective cation channelsIon channelsBiological importanceGlycosylationCation channelsProtein levels