Follicle-Stimulating Hormone Induces a Gap Junction-Dependent Dynamic Change in [cAMP] and Protein Kinase A in Mammalian Oocytes
[摘要] Thesecondmessengercyclicadenosine5′monophosphate(cAMP)hasbeenimplicatedincontrollingmeioticmaturation.Todate,therehavebeennodirectmeasurementsofcAMPinlivingmammalianoocytes.Here,wehaveusedthefluorescentlylabelledcAMP-dependentproteinkinaseA(PKA),FlCRhR,tomonitorcAMPinmouseoocytes.Incumulus-enclosedoocytes,follicle-stimulatinghormone(FSH)stimulatedanincreaseintheoocyte[cAMP]thatwaspreventedbyusingthegapjunctioninhibitor,carbenoxolone.TheFSH-inducedincreaseinoocyte[cAMP]wassuppressedinatime-dependentmannerbypriorexposuretoATP,whileepidermalgrowthfactorhadnoeffectonbasalorstimulatedlevelsofcAMP.Finally,usingconfocalmicroscopy,weshowthattheregulatoryandcatalyticsubunitsofthemicroinjectedPKAaredistributedinapunctatemannerwithastrongeraccumulationintheperinuclearregion.Onanincreasein[cAMP],inresponsetophosphodiesteraseinhibitionorFSH,thecatalyticsubunitdiffusedthroughoutthecytoplasmandgerminalvesicle,whiletheregulatorysubunitremainedanchored.TheseexperimentsshowthatincreasesincAMPinovariansomaticcellsarecommunicatedviagapjunctionstotheoocyte,whereitcanleadtoaredistributionofthecatalyticsubunitofPKA.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] cAMP;FlCRhR;PKA;ATP;AKAP;oocyte;gap junction;ovary;mouse [时效性]
