MOLECULE ƊAYA NA RNA NE YA FARA KOMAI?

Kowace ƙwayar halitta mai rai tana mayar da bayanan gado zuwa sunadarai (proteins) da inji ɗaya: ribosome. Yana aiki da fiye da transfer RNAs 100 da wasu enzymes da dama da ke ɗora musu amino acids. Ta yaya irin wannan tsari mai haɗe-haɗe zai taɓa bayyana? Ribosome yana buƙatar sunadarai don ya yi aiki da inganci — amma sunadarai suna buƙatar ribosome don a yi su.

Tsoffin bayanai kowannensu yana cin karo da wani nau’in wannan wuyar warwarewa. A cikin “duniyar RNA”, RNA ne ya fara; a cikin “duniyar sunadarai”, sunadarai ne; a cikin samfuran haɓaka tare (co-evolution), dukansu sun girma tare. A cewar Alice Cleynen ta University of Montpellier da CNRS, da Archa Fox da Nikolay Shirokikh na University of Western Australia, dukkansu suna barin gibi: ba sa bayyana yadda halaye masu amfani za su iya samuwa kuma a zaɓe su kafin kwayoyin halitta (genes) da tasirinsu su haɗu a zahiri.

Molecule ɗaya mai ayyuka biyu

Shawararsu ita ce riboreplisome: wani tsohon molecule na RNA wanda duka ya kwafi kansa kuma ya aiwatar da matakan farko na gina sunadarai (protein synthesis). A wannan ra’ayi, kwafi (replication) da fassara (translation) sun fara ne a matsayin ayyuka biyu na molecule ɗaya. Ribosomal, transfer da messenger RNAs dukkansu za su fito daga gare shi.

Marubutan sun dogara ne a kan gwaje-gwajen baya-bayan nan. Wani polymerase ribozyme mai tsawon nucleotides 45 kawai, wanda ya haɓaka daga jerin bazuwar, zai iya yin igiyarsa ta abokin tarayya da kwafin kansa, in ji su. Ribosomes da aka ɗaure rabinsu biyu a cikin sarƙar RNA ɗaya har yanzu suna aiki. Gutsuttsura na kusan nucleotides 67 daga zuciyar catalytic ta ribosome za su iya samar da haɗin peptide. Kuma an nuna cewa RNA zai iya maƙala amino acids a jikinsa a cikin ruwa, a pH na tsaka-tsaki.

Matakai goma sha biyu zuwa ƙwayar halitta

Takardar ta zayyana hanya mai matakai 12:

Matakai 1–2, su kaɗai ne “ba na Darwin ba”: gajerun RNAs suna haɗuwa zuwa molecule da zai iya kwafi; sannan haɗuwa bibbiyu tana taƙaita kwafin zuwa “kai”. Daga nan, zaɓin halitta yana gudana ba tare da tsayawa ba.
Mataki na 3: mai kwafin yana ɗora amino acid a ƙarshensa — haihuwar riboreplisome, yanzu “cikakken tsarin gado”.
Matakai 4–8: yana ƙware a wasu amino acids, yana gina gajerun peptides, yana ninka kansa; ƙarin kwafi suna zama proto-transfer RNAs, kuma tarin lambobin coding yana faɗaɗa.
Mataki na 9: wani sashe mai motsi yana aiki kamar messenger RNA.
Matakai 10–12: kasancewa a cikin membrane ko ɗigon ruwa yana riƙe kayayyakin kusa; daga ƙarshe proto-ribosome ya rabu zuwa ƙananan sassansa biyu, kuma asalin molecule ɗin ya zama genome na RNA.

Zanen matakai 1 zuwa 5: gajerun gutsuttsuran RNA suna haɗuwa, replicase yana kwafin kansa, sannan ɗora amino acids da gina gajeren peptide.

Matakai 1 zuwa 5 na hanyar da aka gabatar. Alamomin taurari ja suna nuna matakai biyu da ba na Darwin ba; zaɓin Darwin yana farawa bayan mataki na 2. — Hoto na 2, Cleynen, Fox & Shirokikh (2026), arXiv:2609.30816.

Samfura uku, ƙarshe ɗaya

Marubutan sun kwatanta molecule ɗinsu ɗaya da “miyar RNA” wadda a cikinta molecules daban-daban dole su haɗa kai.

Taswirar dacewa (fitness landscapes): idan akwai ƙarancin hulɗa tsakanin matakai, taswirar tana da kusan ƙoli na gida 11; da ƙaƙƙarfan dogaro da juna na miya, kusan 155. Juyin halitta yana makale sau da yawa a cikin miyar.
Bayanai: daga cikin bits 165 na bayanai masu aiki, 65 (39%) dole su samu kwatsam a matakai biyu na farko. Waɗannan matakai biyu suna ɗauke da fiye da 99.99% na lokacin jira; sauran goman suna biyo baya da sauri.
Kwaikwayon al’umma: a cikin zuriya 500, dacewar riboreplisome ta tashi daga 1.0 zuwa 2.61, yayin da ta miyar ta faɗi zuwa 0.46 — tazarar ninki 5.69. Babban mai laifi shi ne yaɗuwa (diffusion): kayayyaki masu amfani suna yawo nesa da kwayoyin halittar da suka yi su. Cire molecules masu yaudara bai taimaka sosai ba.

Hoto mai sassa huɗu da ke kwatanta molecule ɗaya da aka haɗa da molecules huɗu masu haɗin kai: yiwuwar kaiwa ga mafi kyawun mafita, matrices na sauyi, dacewa a tsawon lokaci, da zanen sanduna na ninkin sauyi.

Molecule ɗaya da aka haɗa da miyar RNAs masu haɗin kai: dacewar riboreplisome tana hawa yayin da ta miyar ke raguwa; yaɗuwar kayayyaki ita ce babbar matsala. — Hoto na 4, Cleynen, Fox & Shirokikh (2026), arXiv:2609.30816.

Ka’idar da ke jiran gwaje-gwajenta

Wannan hasashe ne, ba bincike da aka gano ba: takardar ba ta ba da rahoton wani sabon gwaji ba, kuma samfuranta sun dogara ne a kan ƙiyasin ma’auni. Wasu alƙaluma ba su yi daidai ba a cikin rubutun — misali, an ba da yiwuwar kaiwa ga mafi kyawun mafita a matsayin 5% a wani wuri da kuma kusan 30% a cikin hotuna. Marubutan sun ba da hanyoyi huɗu na gwada shi: haɓaka ƙananan riboreplisomes a ɗakin gwaje-gwaje, neman alamominsu a cikin ribosomal RNA, duba cewa fassara ta molecule ɗaya tana jure masu yaudara, da sake gina tsaka-tsakin da aka hasashe. Asalin riboreplisome mai yiwuwa ya ɓace, in ji su, amma ragowarsa na iya wanzuwa a cikin RNA na kowace ƙwayar halitta.