Cardiomyocytesrequireprecisegeneregulationprogramstopreventpathophysiology.Upregulationofcardiac remodelinggenesresultsincardiomyocytehypertrophyanddecreasedheartfunction.Whilemuchisknown aboutthetranscriptionfactorsthatdrivecardiomyocytespecificgeneexpression,wehavealimited understandingofhowhistoneposttranslationalmodificationsregulatecardiomyocytedevelopmentand maintenance.PolycombRepressiveComplex2(PRC2)isahistonemodifyingcomplexthatsilencesgene expressionbytri-methylatinglysine27onhistoneH3.Conditionalknockoutstudiesshowtheabsenceof PRC2,duringmouseheartdevelopment,resultsinupregulationofcardiomyocytespecifictranscriptionfactors andcardiachypertrophy.However,thereisalackofmechanisticunderstandingregardinghowPRC2 regulatescardiomyocytespecificgenes.EmergingevidencedemonstratesthathumanPRC2isrecruitedto chromatinthroughaninteractionwithasetofaccessoryproteinsknownasAEBP2andPCLproteins.This proposalwillutilizePRC2separation-of-functionmutationstotestthehypothesisthattheinteractionbetween PRC2andtheseaccessoryproteinsisnecessaryforregulatingcardiomyocytespecificgenesandfor preventingcardiomyocytehypertrophy.High-throughputsequencingandimmunocytochemistryapproaches willbeusedtodeterminewhetherAEBP2orPCLproteinsis/areresponsibleformaintainingthetranscriptional profileandphenotypeofcardiomyocytesinaPRC2dependentmanner.Furthermore,live-cellsingle-molecule imagingwillbeusedtodefinehowAEBP2andPCLproteinsaffectthechromatin-bindingdynamicsofPRC2 throughoutcardiomyocytedifferentiation.Theexperimentsinthisproposalrepresentacriticalsteptoward uncoveringthemechanismofPRC2mediatedgene-silencingincardiomyocytes,amechanismthatiscentral tonormalheartdevelopmentandfunction. TrainingPlanSummary:TheproposedresearchwillbecompletedintheUniversityofColoradoBoulder BiochemistryDepartment,locatedinthemultidisciplinaryBioFrontiersBiotechnologybuilding.Theapplicant willdrawfromlocalexpertiseinthefieldsofcardiomyocytebiology,computationalbiology,chromatinbiology, andtranscriptionalregulationtodevelopintoanindependentphysician-scientistthatiswellversedin mechanismsofgeneregulation.Theapplicant?strainingplanincludestakingcoursework,receivingindividual mentorship,attendingconferences,givingoralpresentations,andpreparing/submittingmanuscripts.

Public Health Relevance

ThisproposalwillstudyhowPolycombRepressiveComplex2regulatescardiomyocytespecificgene expression.Findingsgeneratedfromtheproposedaimswillexpandourunderstandingofamechanismthat governsproperheartdevelopment,function,andcouldprovidepathwaysforfuturecardiomyopathytherapies.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30HL147499-02
Application #
9932123
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Meadows, Tawanna
Project Start
2019-05-15
Project End
2023-05-14
Budget Start
2020-05-15
Budget End
2021-05-14
Support Year
2
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Colorado at Boulder
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
007431505
City
Boulder
State
CO
Country
United States
Zip Code
80303