Ngaba ujongene noxinezeleko lobomi bokuqala?
Iimpuku ezikhuliswe phantsi kweemeko zoxinzelelo zinokuziqhelanisa nazo njengabantu abadala-kwaye inokudlulisela lo mkhwa kwiintsana zazo.
NguKate Yandell | NgoNovemba 18, 2014
Izifundo ezininzi zibonisa ukuba uxinzelelo olufunyanwa kwizilwanyana ezincinci kakhulu okanye ebantwini lunokuba nefuthe elibi kwimpilo yengqondo nengqondo enokudluliselwa kamva kubantwana ngokusebenzisa ukuguqulwa kwe-epigenetic. Kodwa uxinzelelo lobomi obusebancinci kwiigundane linokuba neempembelelo ezilungileyo ezinokuthi zidluliselwe kwizidulana, ngophando olushicilelwe namhlanje (ngo-Novemba 18) e Nature Communications. Amantshontsho eempuku zamadoda ezixinzelelweyo zazinokuziphatha ngokuguquguqukayo, njengoko kubonisiwe kukwazi kwawo ukugqiba imisebenzi efuna ukulinda okanye ukulungisa indlela yokuziphatha ixesha elide. Kwaye aba bantwana batshintshe uhlengahlengiso kwi-hippocampi yabo kwi-histones enxulumene ne-mineralocorticoid receptor gene, ebandakanyekayo ekuphenduleni koxinzelelo.
“Abantu babonakalise amatyeli amaninzi ukuba iimpembelelo ezimbi zoxinzelelo zinokudluliselwa kwisizukulwana esilandelayo,” utshilo UDeena WalkerI-postosocence ye-neuroscience kwisikolo iMount Sinai School of Medicine kwisiXeko saseNew York engabandakanyekanga kuphando. “Kuy umdla. . . ngoku sibona ezinye zeziphumo eziluncedo zoxinzelelo zidluliswa, ngokunjalo. ”
"Ifuthe loxinzelelo lunokuba lubi ngokubanzi, kodwa [lisenokubonelela ngamacala aqinisekileyo," utshilo ofundayo Isabelle Mansuy, Unjingalwazi we-neuroepigenetics kwiYunivesithi yaseZürich kunye neSwitzerland Federal Institute of Technology.
UMansuy noogxa bakhe baphantsi kweempuku ezisandul'ukuzalwa kuqhawulo-mtshato olungalawulekiyo kudityaniswa noxinzelelo lwe-maternal (i-MSUS) kwiiveki ezimbini. I-MSUS ibandakanya ukuthatha oomama bentsana ngexesha elingalindelekanga kwaye ibeke oomama babo kwiimeko zoxinzelelo, ezifana nokubekwa kwiibhubhu ezixineneyo okanye kwiindebe zamanzi abandayo. Iqela "lizama ukuphinda-phinda iimeko ezixakekileyo ngexesha lobomi bebancinci kubandakanya ukungakhathalelwa, ukungaqiniseki, kunye nokukhathalelwa okungathembekanga, utshilo uMansuy.
Abaphandi emva koko benza ukuba iimpuku zigqibe imisebenzi ebifuna ukuba balandele ngokukhawuleza imithetho etshintsha ngokukhawuleza ukufumana amanzi nokutya. Umzekelo, kwinto enye, iigundane zafumana umvuzo ukuba zingqengqisa iimpumlo zazo emngxunyeni ngexesha elifanelekileyo emva kokulibaziseka, zityelwe kukukhanya. Xa ulibaziseko lwalulifutshane, ulawulo kunye neempuku ze-MSUS zenza ngokufanayo, kodwa ngokulibaziseka ixesha elide, iimpuku ezazicinezelwe kwangoko ebomini. Xa abaphandi bayihlafunayo inkunzi ye-MSUS yamadoda asetyhini-uhlobo lwendalo, loo nto yaphumela kuvavanyo lwempumlo.
Abaphandi bakwenziwe ezinye iimvavanyo ngabantwana ababhinqileyo kuphela kwaye ngaphandle kootata, kuba le misebenzi yayifuna iimpuku zezindlu kwiikheji zeqela ezinokuthi ziphazamise iihemerarchies zamadoda. Kunye kuvavanyo, iigundane zaqala ukufumana isiselo ukuba ziyahlula-hlula ngokutyelela iikona ezimbini zekheyiya enye kwenye. Emva kwexesha, izilwanyana zafumana umvuzo kuphela xa ziye zashenxiswa kabini phakathi kwezinye iimbombo zekheji. Iintombi zeempuku ze-MSUS zigqibezele ngempumelelo imisebenzi rhoqo kunokulawula izilwanyana.
“Ndicinga ukuba [i-MSUS] inika ithuba kwiimeko ezinzima,” utshilo uMansuy. Kungenxa yokuba [iimpuku] zibekwe phantsi kweemeko ezoyikisayo. . . Benza izicwangciso zokuba bhetele xa ubomi babo busongelwa. ”
Emva koko abaphandi baqala ukugqiba ukuba bezifumana njani kwaye zigqitha njani kule mikhwa yokuziphatha. Benze isigqibo sokuvavanya ukubonakaliswa kwe-mineralocorticoid receptor, edlala iindima ekuphenduleni koxinzelelo, ukuxhalaba, kunye nokuziphatha okujolise kwinjongo. Bafumanise ukuba ayichazwanga kakhulu kwi hippocampi yeempuku zeMSUS kunye namantshontsho abo. Ngelixa amanqanaba e-methylation e-DNA phakathi kolawulo kunye neempuku ezigxininisiweyo kwi-mineralocorticoid receptor zazifana, i-acetylation kwaye ezinye iintlobo ze-methylation ze-histones eziseduze zancitshiswa kwinzala yeempuku ze-MSUS.
Xa abaphandi bajova iigundane ngee-enzymes ezithintela i-acetylation kunye ne-methylation, intetho ye-mineralocorticoid receptor yacinezelwa. Ngokukwanjalo, xa bajova iimpuku ngezi enzymes okanye bevala i-mineralocorticoid receptor, iimpuku zibonisa utshintsho olufanayo lokuziphatha kwezibonwa kwiimpuku ze-MSUS. Iqela "lenze umsebenzi omnandi ngokwenene besebenzisa i-pharmacological inhibitors ukwenza uhlobo lokuphindaphinda into abayibonileyo noxinzelelo," utshilo u-Walker.
Ayikacaci ncam ukuba iimpuku zamadoda ezixinzelelweyo zidlulisela njani kwindlela eziziphatha ngayo kumantshontsho. Abaphandi bafumanise ukuba isidoda sootata abaxinzelelweyo baphakanyise i-methylation ye-DNA kwisikhuthazi se-mineralocorticoid receptor.
kodwa USara Kimmins, ugqirha wezazalo ofundayo epigenetics kwiYunivesithi yaseMcGill eMontreal, akafumananga ukuba iziphumo ze-DNA methylation zinentsingiselo. “Imethylation yakho iphakathi kwempazamo yakho,” utshilo. Ngaphezu koko, wathi amanqanaba e-methylation asezantsi kangangokuba ayengenakulindeleka ukuba ibe nefuthe lebhayoloji.
UMansuy uthi uninzi lwezinye iinguqu ze-epigenetic zinokuba negalelo ekudluliseleni umkhwa. Umzekelo, umsebenzi wangaphambili kwilebhu yakhe ubonakalisile ukuba utshintsho kwi-RNA yobuninzi be-RNA kwi-sperm can Dlulisa iimpembelelo zentlungu kwizizukulwana ngezizukulwana.
Ukutshintshwa kwe-epigenetic kwi-sperm yokubaleka njani ukuphinda i-epigenetic reprogramming eza emva kokuba isichumisi seqanda ingaziwa. Into eqhelekileyo yoxinzelelo lwabazali eneziphumo kwisizukulwane esilandelayo siyinyani, utshilo uKimmins. Umbuzo ngukuthi: Kwenzeka njani?
UMansuy wathi ilebhu yakhe iyaqhubeka nokusebenza ekuqondeni ukuba iziphumo ze-MSUS zidluliselwa njani kwizizukulwana ezizayo. Okwangoku, isifundo esikhoyo sicebisa ukuba abaphandi baqwalasele ukungahoyi isilivere. "Kwakumangalisa ukubona ukuba indlela yokuziphatha eguquguqukayo ibonwa kwimisebenzi eyahlukeneyo, ukuba yaqwalaselwa kumadoda nabasetyhini, kwaye yadluliselwa kwizizukulwana," utshilo uMansuy.
K. Gapp et al., "Ubomi bexesha loxinzelelo kootata baphucuka ekuziphatheni ngokulula kwindlela yokuziphatha kwabo," Unxibelelwano lweNdalo, I-Doi: 10.1038 / ncomms6466, 2014.
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