% % Ruwan%Perera. European Society of Cardiology Att. Susan Del Gaiso 2035, Route des Colles Les Templiers BP Sophia Antipolis France

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1 Ruwan K. Perera Universitätsmedizin Göttingen Göttingen Herzzentrum Abteilung Kardiologie und Pneumologie European Society of Cardiology Att. Susan Del Gaiso 2035 Route des Colles Les Templiers BP Sophia Antipolis France Herzzentrum Göttingen Abteilung Kardiologie und Pneumologie Ruwan K. Perera Göttingen Briefpost Robert-Koch-Straße Göttingen Adresse 0551 / Telefon 0551 / Fax ruwan.perera@med.uni-goettingen.de Aktenzeichen 18. Juni 2014 Datum DearmembersoftheESCCouncil ThankyouverymuchforawardingmewiththeFirst&Contact&Initiative&Grantwhichenabledmeto makeanextraordinaryscientificexperienceattheuniversityofcaliforniasanfranciscoucsf.my hostpimdmarcocontiandhiscoeworkerspossessexceptionalknowledgeinthefieldof phosphodiesterasebiochemistryandthelaboratoriesarewellequipped.iamthankfulto ProfessorContiandhiscoEworkersespeciallyDr.DelphineMikafortheirincrediblygreat hospitalityandtheirwillingnesstoletmeparticipateintheirdayetoedaylabroutine. DuringmytimeattheUCSFIfurthermorewasabletoattendseveralseminarstoachievean impressionofthehighprofilescientificcommunityclusteredatthebayarea. TheFirst&Contact&Initiative&Grantallowedmetotapthishighlystimulatingscientificenvironment toenrichmyownknowledgeestablishnewcontactsforfuturecollaborationsbutimportantlyto improvesomeofmymethodsthatwereinitiallyestablishedinthecontilabs. TograntmethismultipurposeopportunityIexpressmyhonestgratitudetotheESCCouncil members. Sincerelyyours RuwanPerera

2 Report'on'the'Outcome' Background: 3 5 1cyclic adenosine monophosphate (camp) is a highly versatile ubiquitous second messenger.intheheartbeta1adrenergicreceptor(β1ar)mediatedcampsignalingrequires complex yet rigorous control mechanisms in order to elicit beneficial prompt increases in cardiac output at the same time preventing cardiac dysfunction evoked by excessive stimulation. Over the last 30 years of groundbreaking research the paradigm of camp compartmentationaccordingtowhichcampshallbeconfinedinsubcellularmicrodomains has increasingly gained acceptance. Unlike cell organelles camp microdomains are not confinedbyphysicalbarriers.uncontrolleddiffusionoflocalcamppoolsisratherprevented through directed and localized degradation by camp1hydrolyzing enzymes phosphodiesterases(pdes). Therefore camp microdomains may change more dynamically thanrigidcellularstructuresinresponsetocardiacstressanddisease. Out of the five camp1hydrolyzing PDE families being expressed in rodent cardiomyocytes (PDE ) PDE4 encoded in three individual genes (pde4a' (b' and' (d) by far contributesmostisoformsandsplicevariantstototalcamphydrolyticactivity.importantly thesegenesarehighlyconservedalsoinhumanmyocardiumunderscoringtheimportance ofpde4fornormalβ1ar1campsignalregulation.cardiacpde4activityhasrepeatedlybeen reportedtopreventstress1inducedarrhythmiasinbothrodentandhumanmyocardium 113. Especially PDE4B and PDE4D have been linked to multiple functionally relevant camp microdomains.forinstancepde4bisimplicatedinregulationofthel1typecalciumchannel (LTCC) current and feedback regulation of β 1 1ARs 24 whereas PDE4D isoforms might functionally associate with cellular calcium release and re1uptake units 15. Moreover differentpde4disozymeshavebeenshowntoregulateβ 1 1andβ 2 1ARcAMPsignalstobuild up distinct receptor subtype1specific camp microdomains 67. Only recently b1ar blockers such as metoprolol have been shown to disrupt these β1ar/pde4 microdomains causing inadvertently sustained camp signaling by uncontrolled diffusion 8. In this regard the high abundance of differentially localized PDE41regulated camp microdomains makes PDE4 isoforms interesting candidates for alternative perhaps even isoform1specific therapeutic approaches.

3 Hostinstitution: IusedtheFirst'Contact'Initiative'GranttovisitMDMarcoConti(UniversityofCaliforniaSan Francisco UCSF) who is a world1known expert in the field of cyclic nucleotide phosphodiesterases. His knowledge and that of his co1workers regarding cellular and subcellularcompartmentalizedcampregulationbyphosphodiesterases(pdes)especiallyin cardiomyocytesandtheunderlyingbiochemistryisexceptional.furthermorethecontilabs possess precious PDE subfamily1specific knockout mouse models as well as PDE isoform1 specificantibodiesforimmunoblotting(oftenenoughbeingthesingleonesthatconveyhigh degreesofspecificity).usingsuchoutstandingtoolsoverthepastyearshisgrouppublished numerousstudiesthatsetgroundsforabetterunderstandingofhowcertainpdefamilies regulate especially cardiomyocyte function and how disease1associated changes in PDE expressionandactivityinfactcontributetocardiomyopathyandheartfailure Purposeandoutcome: My visit to the Conti Labs aimed at setting up a future collaboration between both of our laboratories and as a preparation therefore to deepen my knowledge especially about the biochemistryunderlyingpderegulation.importantlyhisgrouphasdevelopedfurtherthe21 steppdeactivityassayinventedbythompson&appleman 13 makingitreadilyapplicableon myocardial tissue and cells. As I recently established this method in our own laboratories analogouslytothatpublishedbyrichteretal. 11 itwashighlybeneficialtolearnhowthis assay is actually performed by the first author himself. Furthermore I could do some effective trouble1shooting by addressing methodological issues we experienced when executingthistechnique. An important asset to our future cooperation is the Conti Labs experience in co1 immunoprecipitation (co1ip) of functionally active subcellular camp signal complexes containingcertainpdeisoforms 6 toassesshowfunctionallyrelevantcardiomyocytecamp microdomainsarebuildupindetailandregulatedbycertainpdeisoforms.learninghowthe highlytalentedpostdocsinthecontilabsperformimmunoprecipitation(ip)andco1ipigot familiar with the pitfalls of IPing and co1iping functionally active PDE subfamilies and isoformstosubsequentlymeasuretheiractivities.

4 AsoneofourownstrengthsliesinFörsterResonanceEnergyTransfer(FRET)basedlive1cell imaging of camp dynamics I myself could contribute by improving the acquisition of the FRET setup in the Conti Lab. Since we mostly analyze camp dynamics in freshly isolated A" C B" D Figure'1.'Adult'cardiomyocyte' i s o l a 4 o n' b y' m o d i fi e d' Langendorff' perfusion.' Hearts' of'mice'aged'8012'weeks'were' q u i c k l y ' e x c i s e d ' a n d' immediately' subjected' to' retrograde' perfusion' on' a' modified' Langendorff' setup' (A).' Upon' perfusion' with' digesgon' enzymes' hearts' become' translucent' and' loose' their' rigidity' a' hint' for' proper' digesgon' of' the' cardiac' connecgve' Gssue' (B).' The' digested' heart' was' quickly' removed' from' the' perfusion' a p p a r a t u s' u n d' c a r e f u l l y' homogenized.' One' drop' of' h o m o g e n a t e' w a s' b r i e fl y' analyzed' by' microscopy' to' asses'the'inigal'cell'quality'(c).' C e l l s ' w e r e' s t e p 0 w i s e' accustomed' to' increasing' concentragons' of' Ca 2+' to' achieve' a' final' concentragon' of'1mm.'therearer'cell'quality' w a s' a g a i n' a n a l y z e d' b y' microscopy'(d).'' ' cardiomyocytes of transgenic mouse models expressing FRET1based cyclic nucleotide biosensors1415 furthermore I established the isolation of adult mouse cardiomyocytes in the Conti Labs. Initially intended as a preparation for our future joint projects the cell isolation setup is already well appreciated by the Conti Labsco1workers. To gain access to facilities for functional readouts such as Ca2+ imaging ion current and contractilitymeasurementsduringmystayinsanfranciscoicontactedphdyiangk.xiang atucdavis(ucd)andvisitedtheirlaboratoriestoevaluateapossiblecollaborationwithhim and PhD Donald M. Bers head of the Pharmacology Department UCD. The meeting was very fruitful and gave perspectives to a joint project between UCSF UCD and HRCG. Howeverdetailsstillneedtobediscussed. InsummarymyvisittoSanFranciscoandDavisenabledbytheFirst'Contact'Initiative'Grant oftheescwasagreatsuccessthatsetgroundsforahighlyvividmulti1sitecollaborationin ordertoinvestigatemolecularcardiacpathologybybenefitingfromworld1leadingexpertise at each location including PDE regulation and biochemistry (UCSF) electrophysiology and Ca2+ imaging (UCD) FRET imaging of cyclic nucleotide dynamics and experimental cardiac diseasemodels(hrcg).

5 Appendix: 1. LehnartS.E.'et'al.Phosphodiesterase4Ddeficiencyintheryanodine1receptor complexpromotesheartfailureandarrhythmias.cell (2005). 2. LeroyJ.'et'al.Phosphodiesterase4BinthecardiacL1typeCa(2)(+)channelcomplex regulatesca(2)(+)currentandprotectsagainstventriculararrhythmiasinmice.the' Journal'of'clinical'investigation (2011). 3. MolinaC.E.'et'al.Cyclicadenosinemonophosphatephosphodiesterasetype4 protectsagainstatrialarrhythmias.journal'of'the'american'college'of'cardiology (2012). 4. MikaD.RichterW.WestenbroekR.E.CatterallW.A.&ContiM.PDE4Bmediates localfeedbackregulationofbeta11adrenergiccampsignalinginasarcolemmal compartmentofcardiacmyocytes.journal'of'cell'science (2014). 5. BecaS.'et'al.Phosphodiesterase4DregulatesbaselinesarcoplasmicreticulumCa2+ releaseandcardiaccontractilityindependentlyofl1typeca2+current.circulation' research (2011). 6. RichterW.'et'al.Signalingfrombeta11andbeta21adrenergicreceptorsisdefinedby differentialinteractionswithpde4.the'embo'journal (2008). 7. XiangY.'et'al.Phosphodiesterase4Disrequiredforbeta2adrenoceptorsubtype1 specificsignalingincardiacmyocytes.proceedings'of'the'national'academy'of' Sciences'of'the'United'States'of'America (2005). 8. RichterW.MikaD.BlanchardE.DayP.&ContiM.beta11adrenergicreceptor antagonistssignalviapde4translocation.embo'reports (2013). 9. Abi1GergesA.'et'al.DecreasedexpressionandactivityofcAMPphosphodiesterases incardiachypertrophyanditsimpactonbeta1adrenergiccampsignals.circulation' research (2009).

6 10. GhigoA.'et'al.Phosphoinositide31kinasegammaprotectsagainstcatecholamine1 inducedventriculararrhythmiathroughproteinkinasea1mediatedregulationof distinctphosphodiesterases.circulation (2012). 11. RichterW.&ContiM.Theoligomerizationstatedeterminesregulatoryproperties andinhibitorsensitivityoftype4camp1specificphosphodiesterases.the'journal'of' biological'chemistry (2004). 12. SetteC.&ContiM.PhosphorylationandactivationofacAMP1specific phosphodiesterasebythecamp1dependentproteinkinase.involvementofserine54 intheenzymeactivation.the'journal'of'biological'chemistry (1996). 13. ThompsonW.J.&ApplemanM.M.Multiplecyclicnucleotidephosphodiesterase activitiesfromratbrain.biochemistry (1971). 14. CalebiroD.'et'al.PersistentcAMP1signalstriggeredbyinternalizedG1protein1 coupledreceptors.plos'biol7e (2009). 15. GotzK.'et'al.TransgenicMiceforRealTimeVisualizationofcGMPinIntactAdult Cardiomyocytes.Circulation'research(2014).