Ukufundwa kwe-DNA yesibani senhlanzi sasendulo esingenamhlathi kwavumela ososayensi bezakhi zofuzo baseRussia ukuthola impendulo yombuzo wokuthi okhokho bethu babuthola kanjani ubuchopho obuyinkimbinkimbi nogebhezi olwaludingeka kulo.
Ukutholakala kofuzo olukhethekile, ukuvela kwalo okwanikeza okhokho bethu ugebhezi nobuchopho, kuchazwa kumagazini iScientific Reports. Ngokusho kuka-Andrei Zaraisky, obemele i-Institute of Bioorganic Chemistry yeRussia Academy of Sciences, isakhi sofuzo i-Anf / Hesx1 sitholakale ku-lamprey, okuyisona esidalwa esinomgogodla esidala kunazo zonke. Ngokusobala, kwaba ukuvela kwalesi sakhi sofuzo okwaba yinguquko lapho okwenzeka khona ukuvela kobuchopho kuma-vertebrate.
Esinye sezici ezibaluleke kakhulu esihlukanisa izilwane ezinomgogodla wesimanjemanje ezingenamgogodla ukuba khona kobuchopho obuyinkimbinkimbi, obuthuthukisiwe. Ngakho-ke, ukuvikela isicubu sezinzwa esibucayi emonakalweni ongaba khona, kwakheke umgodla wokuvikela onzima. Kepha ukuthi leli gobolondo livele kanjani, nokuthi yini eyavela phambilini - i-cranium noma ubuchopho - namanje akwaziwa futhi kuhlala kuyimpikiswano.
Ngethemba lokuthola impendulo yalo mbuzo, ososayensi babonile ukwakheka, ukusebenza nokutholakala kwezakhi zofuzo zama-myxins namalambu, okuyizinhlanzi zakudala kakhulu. Ngokusho kososayensi, lezi zinhlanzi ezingenamhlathi zifana kakhulu nama-vertebrate okuqala ahlala olwandle oluyisisekelo loMhlaba cishe eminyakeni eyizigidi ezingama-400-450 edlule.
Ngokutadisha umsebenzi wezakhi zofuzo emibungwini yesibani, uZaraisky nozakwabo bakwazi ukukhanyisa ngokwengxenye ukuvela kwamagciwane omgogodla, njengoba, njengoba kwaziwa, kufaka abantu. Abaphenyi manje sebenquma ukuthi iziphi izakhi zofuzo eziku-DNA yama-vertebrate futhi ezingezona ezingenamgogodla.
Ngokusho kososayensi bezakhi zofuzo baseRussia, emuva ngonyaka we-1992, bakwazile ukuthola isakhi sofuzo (Xanf) esithakazelisayo ku-DNA yemibungu yamaxoxo, enquma ukukhula kwengaphambili lombungu, kufaka phakathi ubuso nobuchopho. Ngemuva kwalokho kwaphakanyiswa ukuthi yileli geni elingabeka ukukhula kobuchopho nogebhezi nama-vertebrate. Kodwa lo mbono awuzange uthole ukusekelwa, ngoba lesi sakhi sasingekho kuma-myxins nasezibani - ama-vertebrate akudala kakhulu.
Kepha ngokuhamba kwesikhathi lolu hlobo lwatholakala ku-DNA yenhlanzi eshiwo ngenhla, yize isishintshe kancane. Kuthathe imizamo emikhulu ukukwazi ukukhipha uHanf ongaziwa emibungwini futhi kufakazele ukuthi isebenza njenge-analog yayo kwi-DNA yabantu, amaxoxo nezinye izilwane ezinomgogodla.
Kuze kube manje, ososayensi bakhulisa imibungu yezibani ze-Arctic. Ngemuva kwalokho, balinda kwaze kwaba umzuzu lapho ikhanda labo liqala ukukhula khona, base bekhipha kuwo inqwaba yama-molecule e-RNA. La ma-molecule akhiqizwa ngamaseli lapho "efunda" izakhi zofuzo. Ngemuva kwalokho le nqubo yahlehliswa futhi ososayensi baqoqa imicu emifushane ye-DNA. Eqinisweni, angamakhophi ezakhi zofuzo asebenza kakhulu emibungwini yesibani.
Kuvele kwaba lula kakhulu ukuhlaziya ukulandelana okunjalo kwe-DNA. Ukufunda lokhu kulandelana kunikeze ososayensi ithuba lokuthola izinhlobo ezinhlanu ezinokwenzeka zofuzo lweXanf, ngayinye yazo enemiyalo eyingqayizivele yokuhlanganiswa kwamaprotheni. Lezi zinguqulo ezinhlanu azifani neze nalezo ezitholakala emzimbeni wamasele kuma-90 akude.
Umsebenzi walesi sakhi sezibani wafana cishe nentela yayo ku-DNA yama-vertebrate athuthukile. Kepha bekunomehluko owodwa: lesi sakhi sifakiwe emsebenzini kamuva kakhulu. Ngenxa yalokhu, izingebhezi nobuchopho bezibani bancane.
Ngasikhathi sinye, ukufana kwesakhiwo sofuzo lwe-lamprey Xanf kanye ne "frog" i-Anf / Hesx1 kukhombisa ukuthi lesakhi sofuzo, esivele cishe eminyakeni eyizigidi ezingama-550 edlule, sinquma ukuba khona kwama-vertebrate. Kungenzeka, kwaba nguye owayengomunye izinjini main kwemvelo kwamagciwane ngomzimba futhi ikakhulukazi abantu.
