Abstract:Thepituitarygonadotropins(GtHs),follicle-stimulatinghormone(FSH)andluteinizinghormone(LH)regulatesteroidogenesisandorange-spottedgrouper()wasfirstdividedintosevenphases(phaseItophaseVII)accordingtothehistologicalcharacteristicsofoocytes,andthetemporalexpressionpatternsofFSHRandLHRwerefurtherdetectedinparallelwiththeexpressionprofilesofadownstreamfactor(Cyp19a)duringdifferentdevelopmentalphasesoftheovary.Quantitativereal-timePCRdeterminedtheabundanceofFSHRwasatarelativelylowlevelwithin,thenelevatedgraduallyinphaseIII,significantlyincreasedinphaseIVandphaseV,andremarkablydecreasedinphaseVI.Contrastingly,thetranscriptsofLHRremainedatalowlevelduringearlydevelopmentoftheovary(phaseItranscriptionalphaseIII,butsignificantlyincreasedinphaseIVandphaseV,andthensharplydecreasedinphaseVI.Generally,Cyp19ahadasimilarexpressionprofilewithFSHR.Insummary,ourresultssuggestthatbothFSHRandLHRareinvolvedintheregulationofovarydevelopment,butplaydistinctrolesinthedifferentdevelopmentphasesoftheovary.FSHRmaybethemajoractivatorofCyp19atranscription.ThisinvestigationcontributestoelucidatetheactionsofGtH/GtHRsignalsystemsinreproductiveregulationintheorange-spottedgrouper.
