Riceblack-streakeddwarfvirus(RBSDV)isarecognizedmemberofthegenusFijivirus,familyReoviridae.Itsgenomehastendouble-strandedRNA(dsRNA)segments(S1-S10),inwhichthefifthgenomesegment(S5)containstwoopenreadingframes(ORFs)withapartiallyoverlappingregion.ThesecondORFofRBSDVS5encodesaviralnonstructuralproteinnamedp5bwithunknownfunction.Torevealthefunctionofp5b,itsgenewasligatedintothebaitplasmidpGBKT7andanexpressionlibrarycontainingricecDNAswasconstructedusingplasmidpGADT7foryeasttwo-hybridassay.Thebaitproteinp5bwasdetectedinyeastbywesternblot,andtheresultofanauto-activationtestshowedthatp5bcouldnotautonomouslyactivatetheexpressionofreportergenesinyeast.Thenthebaitproteinp5bwasusedforscreeningthecDNAexpressionlibrariesofrice.Genefragmentsofsomepivotalenzymesinvolvedinphotosynthesis,respirationandotherimportantmetabolicprocesses,wereidentifiedtointeractwithp5binyeast,suggestingthattheseinteractionsmayplayrolesinsymptomdevelopmentininfectedplants.
