Xiaoxi Meng ndi Zhikai Liang atapereka lingaliro koyamba zaka zingapo zapitazo, James Schnable anali kukayikira. Kunena zochepa.
"'Chabwino, mutha kuyesa, koma sindikuganiza kuti zigwira ntchito," pulofesa wothandizana nawo wazaulimi ndi ulimi wamaluwa adakumbukira zomwe ananena kwa Meng ndi Liang, omwe anali ofufuza za postdoctoral mu labu ya Schnable ku Yunivesite ya Nebraska-Lincoln.
Analakwitsa ndipo, poganizira zam'mbuyo, sanali wosangalala kukhala. Komabe panthawiyo, Schnable anali ndi chifukwa chabwino chokweza nsidze. Lingaliro la awiriwa - loti ma DNA a mbewu zosamva kuzizira zomwe zimagwera ku chisanu atha kuthandizira kulosera momwe mbewu zakutchire, zolimba kwambiri zimalekerera kuzizira - zinkawoneka ngati zolimba. Kunena zochepa. Komabe, chinali chiwopsezo chochepa, chopereka mphotho yayikulu. Chifukwa ngati Meng ndi Liang angazigwiritse ntchito, zitha kungothamangitsa zoyesayesa zopanga mbewu zosamva kuzizira pang'ono kapena mochulukirapo ngati anzawo omwe samva kuzizira.
Mbewu zina zofunika kwambiri padziko lapansi zinali zowetedwa m'madera otentha - chimanga kum'mwera kwa Mexico, manyuchi kum'mawa kwa Africa - zomwe sizimayika chikakamizo chofuna kusintha chitetezo ku kuzizira kapena kuzizira. Mbewuzo zikabzalidwa kumadera ouma kwambiri, kukhudzika kwawo ndi kuzizira kumalepheretsa kubzala msanga komanso mochedwa momwe zingakololedwe. Nyengo zazifupi zimafanana ndi nthawi yochepa ya photosynthesis, zomwe zimapangitsa kuti pakhale zokolola zazing'ono komanso chakudya chochepa kwa anthu padziko lonse lapansi omwe akuyembekezeka kuyandikira anthu 10 biliyoni pofika 2050.
Kuzizira
Mitundu ya zomera zomwe zimamera kale kumalo ozizira, panthawiyi, zinasintha njira zopirira kuzizira. Atha kukonzanso ma nembanemba awo am'manja kuti asunge madzi pa kutentha kocheperako, kuletsa nembanemba kuti zisaundane ndi kusweka. Amatha kuwonjezera shuga kuzinthu zamadzi zomwe zili mkati ndi mozungulira nembanembazo, ndikuchepetsa kuzizira kwake mofanana ndi momwe mchere umachitira mumsewu. Amatha kupanganso mapuloteni omwe amaphimba tinthu tating'ono tomwe timakhala tokhala ndi ayezi asanakule n'kukhala ma cell.
Chitetezo chonsechi chimachokera pamlingo wa majini, ngakhale osati mu DNA yokha. Zomera zikayamba kuzizira, zimatha kuyankha mwa kuzimitsa kapena kuyatsa majini ena - kuletsa kapena kulola kuti zolemba zawo zama genetic zilembedwe ndikuchitidwa. Choncho, podziwa kuti ndi chibadwa cha zomera ziti zimene sizipirira kuzizira, zomwe zimazimitsa ndi kumapitirizabe chifukwa cha kuzizira kozizira kwambiri, kungathandize ofufuza kumvetsa maziko a mipanda yawoyo, ndipo pamapeto pake, amakonza zodzitetezera ngati zimenezi kuti zikhale mbewu zosamva kuzizira.
Koma Schnable ankadziwanso, monga anachitira Meng ndi Liang, kuti ngakhale jini yofanana nthawi zambiri imayankha mosiyana ndi kuzizira kwa mitundu yonse ya zomera, ngakhale yogwirizana kwambiri. Zomwe zikutanthauza, mokhumudwitsa, kuti kumvetsetsa momwe jini limayankhira kuzizira mumtundu wina kumapangitsa kuti asayansi a zomera adziwe chilichonse chotsimikizira za khalidwe la jini mu mtundu wina. Kusadziŵika kumeneku, kwalepheretsa kuyesetsa kuphunzira malamulo okhudza zomwe zidzatseke kapena kuyambitsa majini.
"Tikadali oyipa kwenikweni pakumvetsetsa chifukwa chomwe majini amazimitsira," adatero Schnable.
Mbewu za chimanga
Popanda bukhu la malamulo, ofufuzawo adatembenukira ku kuphunzira kwamakina, mtundu wanzeru zopanga zomwe zimatha kulemba zake. Anapanga makamaka mtundu woyang'aniridwa - mtundu womwe ungathe, ukaperekedwa ndi zithunzi zokwanira zolembedwa, kunena, amphaka ndi osakhala amphaka, pamapeto pake amaphunzira kusiyanitsa choyambirira ndi chomaliza. Gululi poyamba lidawonetsa mtundu wawo wokhala ndi mulu wokulirapo wa majini otsatizana a chimanga, komanso kuchuluka kwa machitidwe a majiniwo pomwe mbewuyo idazizira kwambiri. Chitsanzocho chinadyetsedwanso "chilichonse chomwe tingaganizire" pa jini iliyonse ya chimanga, Schnable adati, kuphatikizapo kutalika kwake, kukhazikika kwake ndi kusiyana kulikonse pakati pake ndi mitundu ina ya chimanga yomwe imapezeka mu zomera zina za chimanga.
Pambuyo pake, ochita kafukufuku adayesa chitsanzo chawo pobisa chidziwitso chimodzi m'gulu la majiniwo: kaya adayankha kuyambika kwa kutentha kwachisanu, kapena ngati sanayankhe. Posanthula mawonekedwe a majini omwe adawuzidwa kuti anali omvera kapena osayankha, chitsanzocho chinazindikira kuti kuphatikiza kwa zinthuzo kunali kofunikira kwa chilichonse - kenako ndikuyika bwino ambiri mwamitundu yotsala, yachinsinsi-bokosi m'magulu awo olondola.
Chinali chiyambi cholonjeza, mosakayika. Koma chiyeso chenichenicho chinatsalira: Kodi chitsanzocho chingatengere maphunziro chimene chinalandira m’mitundu ina ndi kugwiritsira ntchito mtundu wina?
Yankho lake linali inde wotsimikizika. Ataphunzitsidwa ndi deta ya DNA kuchokera ku mtundu umodzi wokha mwa mitundu isanu ndi umodzi - chimanga, manyuchi, mapira a ngale, mapira a proso, mapira a foxtail kapena switchgrass - chitsanzocho chimatha kuneneratu kuti ndi majini amtundu uliwonse mwa asanu omwe angayankhe kuzizira. Chodabwitsa cha Schnable, chitsanzocho chinagwira ntchito ngakhale pamene chinaphunzitsidwa za mtundu wosazizira - chimanga, manyuchi, ngale kapena mapira a proso - koma ndi ntchito yolosera mayankho a majini mu mapira a foxtail kapena switchgrass.
lachitsanzo
"Zitsanzo zomwe tidaphunzitsa zidagwira ntchito pafupifupi mitundu yonse ya zamoyo ngati kuti muli ndi chidziwitso chamtundu umodzi ndikugwiritsa ntchito zomwe zili mkati kuti mulosere zamtundu womwewo," adatero, kudabwitsa kwake komwe kudabwera miyezi ingapo pambuyo pake. "Sindikananeneratu zimenezo."
"Lingaliro loti titha kungoyika zidziwitso zonse pakompyuta, ndipo limatha kudziwa malamulo ena kuti lilosere zomwe zichitike, likadali lodabwitsa kwa ine."
Maulosi amenewo angakhale othandiza makamaka poganizira njira ina. Kwa zaka pafupifupi khumi, akatswiri a sayansi ya zamoyo za zomera atha kuyeza kuchuluka kwa mamolekyu a RNA - omwe ali ndi udindo wolemba ndi kutumiza malangizo a DNA - opangidwa ndi jini iliyonse ya zomera zamoyo. Koma kuyerekeza momwe mawu a jini amayankhira kuzizira m'zitsanzo zamoyo, komanso zamoyo zambiri, ndi ntchito yovuta, adatero Schnable. Izi ndi zoona makamaka ndi zomera zakutchire, zomwe mbewu zake zimakhala zovuta kupeza. Mbewu zimenezo sizingamere pamene zikuyembekezeredwa, ngati zingatero, ndipo zingatenge zaka kuti zikule. Ngakhale zitatero, mbewu iliyonse yomwe yatuluka iyenera kulimidwa pamalo ofanana, olamulidwa ndi kuphunziridwa pamlingo womwewo.
Mitundu yambiri
Zonsezi zimapangitsa kuti pakhale vuto lalikulu pakukula kwa zinyama zakuthengo zokwanira, kuchokera ku zamoyo zakuthengo zokwanira, kuti zifanane ndi kusanthula momwe majini awo amachitira ndi kuzizira.
"Ngati tikufunadi kudziwa zomwe majini ali ofunikira - omwe amathandizira momwe mbewuyo imasinthira kuzizira - tiyenera kuyang'ana mitundu yopitilira iwiri," adatero Schnable. "Tikufuna kuyang'ana gulu la zamoyo zomwe zimalekerera kuzizira ndi gulu lomwe limakhala lovuta, ndikuyang'ana machitidwe: "Jini lomweli nthawi zonse limayankha mumodzi ndipo nthawi zonse silimayankha lina."
"Izi zimayamba kukhala kuyesa kwakukulu komanso kokwera mtengo. Zikadakhala zabwino ngati titha kungolosera kuchokera kumayendedwe a DNA a mitundu imeneyo m'malo, tinene, kutenga mitundu 20 ndikuyesera kuti zonse zikhale pamlingo womwewo, kuziyika zonse kudzera m'machiritso omwewo, komanso kuyeza kuchuluka kwa RNA yopangidwa pa jini iliyonse pamtundu uliwonse.”
Mwamwayi chitsanzochi, ofufuza adatsata kale ma genome a mitundu yopitilira 300 ya zomera. Kuyesayesa kosalekeza kwapadziko lonse kungapangitse kuti chiŵerengerocho chifike pa 10,000 pazaka zingapo zikubwerazi.
Ngakhale mtunduwo wadutsa kale zomwe amayembekeza, Schnable adati chotsatiracho chiphatikiza "kudzitsimikizira tokha komanso anthu ena" kuti chikugwira ntchito monga momwe zakhalira mpaka pano. M'mayesero aliwonse mpaka pano, ofufuza adafunsa chitsanzocho kuti awauze zomwe amadziwa kale. Iye anati, chiyeso chachikulu chidzachitika pamene anthu onse ndi makinawo ayamba kumene.
"Kuyesa kwakukulu kwina komwe ndikuganiza kuti tikuyenera kuchita ndikulosera za zamoyo zomwe tilibe chidziwitso chilichonse," adatero. "Kutsimikizira anthu kuti zimagwira ntchito nthawi zomwe ngakhale ife sitikudziwa mayankho."
Gululi linanena zomwe lapeza m'magazini yotchedwa Proceedings of the National Academy of Sciences. Meng, Liang ndi Schnable adalemba phunziroli ndi Rebecca Roston wa ku Nebraska, Yang Zhang, Samira Mahboub ndi wophunzira wamaphunziro apamwamba a Daniel Ngu, pamodzi ndi Xiuru Dai, katswiri woyendera kuchokera ku Shandong Agricultural University.
Kuti mudziwe zambiri:
Yunivesite ya Nebraska Lincoln
www.unl.edu