Mutant Stem Cells sun sabawa Dokokin Ci gaba

Ka yi tunanin kana yin burodi, amma gishiri ya ƙare. Ko da tare da abin da ya ɓace, batter ɗin yana kama da batter na cake, don haka kuna manne shi a cikin tanda kuma ku ƙetare yatsun ku, kuna tsammanin ƙare da wani abu mai kyau kusa da cake na yau da kullum. Maimakon haka, sai ku dawo bayan sa'a guda don nemo cikakken nama da aka dafa.

Yana jin kamar wasa mai amfani, amma irin wannan sauyi mai ban tsoro shine ainihin abin da ya faru da tasa na ƙwayoyin linzamin kwamfuta lokacin da masana kimiyya a Cibiyar Gladstone suka cire kwayar halitta guda ɗaya kawai - ƙwayoyin tushe waɗanda aka ƙaddara su zama ƙwayoyin zuciya ba zato ba tsammani sun yi kama da masu zuwa ga ƙwayoyin kwakwalwa. Binciken damar masana kimiyyar shine haɓaka abin da suke tunanin sun sani game da yadda ƙwayoyin sel suke juyewa zuwa sel balagaggu da kiyaye ainihin su yayin da suke girma.

"Wannan da gaske yana ƙalubalanci mahimman ra'ayoyi game da yadda sel ke tsayawa a hanya da zarar sun fara kan hanyarsu ta zama ƙwayoyin zuciya ko kwakwalwa," in ji Benoit Bruneau, PhD, darektan Cibiyar Gladstone na Ciwon Zuciya da kuma babban marubucin sabon binciken da aka buga a cikin. Halitta.

Babu Juya Baya

Kwayoyin da ke cikin mahaifa suna da yawa-suna da ikon bambanta, ko canza su, zuwa kowane nau'in tantanin halitta a cikin cikakkiyar halittar jiki mai girma. Amma yana ɗaukar matakai da yawa don ƙananan ƙwayoyin cuta don haifar da nau'in tantanin halitta. A kan hanyarsu ta zama ƙwayoyin zuciya, alal misali, ƙwayoyin ƙwanƙwasa embryon sun fara bambanta zuwa mesoderm, ɗaya daga cikin tsoho kyallen takarda guda uku da aka samu a cikin embryo na farko. A ƙasan hanyar, ƙwayoyin mesoderm sun rabu don yin ƙasusuwa, tsokoki, tasoshin jini, da bugun ƙwayoyin zuciya.

An yarda da cewa da zarar tantanin halitta ya fara bambanta ɗaya daga cikin waɗannan hanyoyi, ba zai iya juyawa don zaɓar wata makoma ta daban ba.

“Pretty much every scientist who talks about cell fate uses a picture of the Waddington landscape, which looks a lot like a ski with different ski slopes descending into steep, separated valleys,” says Bruneau, who is also the William H. Younger Chair in Cardiovascular Research at Gladstone and a professor of pediatrics at UC San Francisco (UCSF). “If a cell is in a deep valley, there’s no way for it to jump across to a completely different valley.”

Shekaru goma da suka gabata, Babban Mai bincike na Gladstone Shinya Yamanaka, MD, PhD, ya gano yadda ake sake tsara sel masu girma dabam dabam zuwa sel masu ƙarfi da yawa. Duk da yake wannan bai bai wa sel damar yin tsalle tsakanin kwaruruka ba, ya yi aiki kamar ɗaga kan ski baya zuwa saman yanayin banbanta.

Tun daga wannan lokacin, wasu masu bincike sun gano cewa tare da madaidaicin sinadarai, ana iya canza wasu kwayoyin halitta zuwa nau'ikan da ke da alaƙa ta hanyar tsarin da ake kira "reprogramming kai tsaye" -kamar hanyar gajeriyar hanya ta cikin dazuzzuka tsakanin hanyoyin tseren kankara. Amma babu ɗaya daga cikin waɗannan al'amuran sel waɗanda zasu iya tsalle ba tare da bata lokaci ba tsakanin hanyoyin banbance-banbance. Musamman ma, ƙwayoyin mesoderm ba za su iya zama farkon nau'ikan nau'ikan nisa kamar ƙwayoyin kwakwalwa ko ƙwayoyin hanji ba.

Amma duk da haka, a cikin sabon binciken, Bruneau da abokan aikinsa sun nuna cewa, ga mamakin su, abubuwan da ke haifar da ƙwayoyin zuciya za su iya canzawa kai tsaye zuwa abubuwan da suka faru a cikin kwakwalwa - idan wani furotin da ake kira Brahma ya ɓace.

Abun Mamaki

Masu binciken sun yi nazarin rawar da sunadaran Brahma ke takawa wajen bambance bambancen sel na zuciya, saboda sun gano a cikin 2019 cewa yana aiki tare da sauran kwayoyin da ke da alaƙa da samuwar zuciya.

A cikin kwano na ƙwayoyin ƙwai na linzamin kwamfuta, sun yi amfani da hanyoyin gyaran gyare-gyare na CRISPR don kashe kwayoyin halittar Brm (wanda ke samar da furotin Brahma). Kuma sun lura cewa sel sun daina bambancewa zuwa na al'ada na ƙwayoyin zuciya.

“Bayan kwanaki 10 na banbance-banbance, sel na yau da kullun suna bugun jini; a fili suke ƙwayoyin zuciya ne,” in ji Swetansu Hota, PhD, marubucin farko na binciken kuma masanin kimiyyar ma’aikata a cikin Lab ɗin Bruneau. "Amma ba tare da Brahma ba, akwai kawai tarin sel marasa ƙarfi. Babu duka ko kadan."

Bayan ƙarin bincike, ƙungiyar Bruneau ta fahimci dalilin da yasa ƙwayoyin ba sa bugun jini shine saboda cire Brahma ba wai kawai kashe kwayoyin halittar da ake buƙata don ƙwayoyin zuciya ba, har ma da kunna ƙwayoyin da ake buƙata a cikin ƙwayoyin kwakwalwa. Kwayoyin precursor na zuciya yanzu sun kasance sel precursor na kwakwalwa.

Masu binciken sun bi kowane mataki na bambance-bambance, kuma ba zato ba tsammani sun gano cewa waɗannan kwayoyin halitta ba su sake komawa cikin yanayi mai yawa ba. Madadin haka, sel ɗin sun yi tsalle mai girma tsakanin hanyoyin tantanin halitta fiye da yadda aka taɓa gani a baya.

"Abin da muka gani shi ne cewa tantanin halitta a cikin kwarin daya na filin Waddington, tare da kyawawan yanayi, na iya tsalle zuwa wani kwari daban ba tare da fara ɗagawa zuwa koli ba," in ji Bruneau.

Darussan Cuta

Yayin da mahallin sel a cikin kwanon dakunan gwaje-gwaje da kuma cikin mahaifa duka ya bambanta sosai, abubuwan da masu binciken suka yi suna ɗauke da darussa game da lafiyar ƙwayoyin cuta da cututtuka. Maye gurbi a cikin kwayar halittar Brm an danganta su da cututtukan zuciya da aka haifa da kuma cututtukan da suka shafi aikin kwakwalwa. Hakanan kwayar halitta tana da hannu cikin cututtukan daji da yawa.

"Idan cire Brahma zai iya juyar da ƙwayoyin mesoderm (kamar ƙwayoyin zuciya) zuwa sel ectoderm (kamar ƙwayoyin ƙwayoyin ƙwayoyin cuta) a cikin tasa, to watakila maye gurbi a cikin gene Brm shine ke ba wa wasu kwayoyin cutar kansa ikon canza tsarin kwayoyin halitta." in ji Bruneau.

Har ila yau, binciken yana da mahimmanci a matakin bincike na asali, in ji shi, kamar yadda za su iya ba da haske kan yadda kwayoyin halitta zasu iya canza halin su a cikin saitunan cututtuka, irin su ciwon zuciya, da kuma bunkasa hanyoyin kwantar da hankali, ta hanyar haifar da sababbin ƙwayoyin zuciya alal misali.

"Bincikenmu kuma ya gaya mana cewa hanyoyin bambance-bambancen sun fi rikitarwa da rauni fiye da yadda muke tunani," in ji Bruneau. "Mafi kyawun sanin hanyoyin bambancewa zai iya taimaka mana mu fahimci zuciyoyin da aka haifa - da sauran - lahani, waɗanda ke tasowa ta wani ɓangare ta hanyar bambance-bambance."

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Shafin Farko