Abaphandi abavela kwiSebe leBiochemistry kwiZiko leSayensi laseIndiya (IISc) baye bafumanisa indlela ekudala ifunwa esetyenziswa zizityalo zomhlaba zamandulo ezifana ne-bryophytes (kubandakanywa ubulembu kunye ne-liverworts)lawula ukukhula kwezityalo– inkqubo ethe yalondolozwa kwizityalo ezisandula ukuvela.
Uphononongo, olupapashwe kwiphephancwadi i-Nature Chemical Biology, lujolise kulawulo olungelulo lweklasikhi yeprotheni ye-DELLA, umlawuli wokukhula oyintloko onokuthintela ukuhlukana kweeseli kwizityalo ze-embryonic (izityalo zomhlaba).
"UDELLA usebenza njengesantya, kodwa ukuba le santya sihlala sikhona, isityalo asikwazi ukuhamba," kuchaza uDebabrata Laha, unjingalwazi onxulumene ne-biochemistry kunye nombhali-mbhali wophononongo. Ke ngoko, ukuthotywa kweeproteni ze-DELLA kubalulekile ekukhuthazeni ukukhula kwezityalo. Kwizityalo zeentyatyambo, i-DELLA iyancipha xa i-phytohormoneigibberellin (GA)ibophelela kwi-receptor yayo i-GID1, eyenza i-GA-GID1-DELLA eyinkimbinkimbi. Emva koko, iprotein ye-DELLA ye-repressor ibophelela kumatyathanga e-ubiquitin kwaye ithotywe yi-26S proteasome.
Okubangel 'umdla kukuba, ii-bryophyte zaziphakathi kwezityalo zokuqala ezakha umhlaba, malunga nezigidi ezingama-500 kwiminyaka eyadlulayo. Nangona bavelisa i-phytohormone gibberellin (GA), abanalo i-GID1 receptor. Oku kuphakamisa umbuzo: kwakulawulwa njani ukukhula nophuhliso lwezi zityalo zamandulo?
Abaphandi basebenzise inkqubo ye-CRISPR-Cas9 ukunkqonkqoza i-VIH gene ehambelanayo, ngaloo ndlela iqinisekisa indima ye-VIH. Izityalo ezingenayo i-enzyme ye-VIH esebenzayo zibonakalisa ukukhula okukhulu kunye neziphene zophuhliso kunye nokungahambi kakuhle kwe-morphological, njenge-thallus exineneyo, ukukhula kwe-radial okungahambi kakuhle, kunye nokungabikho kwe-calyx. Ezi ziphene zalungiswa ngokuguqula i-genome yesityalo ukuvelisa kuphela isiphelo esinye (i-N-terminus) ye-enzyme ye-VIH. Ukusebenzisa iindlela eziphambili ze-chromatography, iqela lophando lifumene ukuba i-N-terminus iqulethe i-kinase domain eyenza ukuveliswa kwe-InsP₈.
Abaphandi bafumanisa ukuba i-DELLA yenye yeethagethi zeselula ze-VIH kinase. Ngapha koko, baqaphela ukuba i-phenotype yezityalo ezinqongopheleyo ze-MpVIH zazifana nezityalo ze-Miscanthus multiforme kunye nokubonakaliswa kwe-DELLA okwandisiweyo.
"Okwangoku, sizimisele ukufumanisa ukuba ukuzinza kwe-DELLA okanye umsebenzi uyaphuculwa kwizityalo ezinqongopheleyo ze-MpVIH," utshilo uPriyanshi Rana, umfundi ogqirha kwiqela lophando likaLahey kunye nombhali wokuqala wephepha. Ngokuhambelana ne-hypothesis yabo, abaphandi bafumanise ukuba inhibition ye-DELLA ibuyisele kakhulu ukukhula kunye neziphene zophuhliso kwizityalo eziguqukayo ze-MpVIH. Ezi ziphumo zibonisa ukuba i-VIH kinase ilawula kakubi i-DELLA, ngaloo ndlela ikhuthaza ukukhula kwezityalo kunye nophuhliso.
Abaphandi badibanisa iindlela zofuzo, i-biochemical, kunye ne-biophysical ukucacisa indlela i-inositol pyrophosphate elawula ngayo i-DELLA iprotheyini yokubonakaliswa kule bryophyte. Ngokukodwa, i-InsP₈, eveliswe nguMpVIH, ibophelela kwiprotheni ye-MpDELLA, ikhuthaza i-polyubiquitination yayo, nto leyo ekhokelela ekuthotyweni kwale proteni yokucinezela yiproteasome.
Uphando ngeprotein ye-DELLA lusukela emva kuHlaziyo loHlaza, xa izazinzulu ziye zasebenzisa ngokungaziyo amandla alo okwenza iintlobo ezivelisa isivuno esiphezulu se-semi-dwarf. Nangona indlela yokusebenza kwayo yayingaziwa ngelo xesha, ubuchwephesha bale mihla buye benza ukuba izazinzulu zisebenzise ukuhlelwa kofuzo ukuze zilawule umsebenzi wale proteni, ngaloo ndlela zandisa ngempumelelo izivuno zezityalo.
“Ngokukhula kwabemi kunye nokuncipha komhlaba olimekayo, ukwanda kwezivuno zezityalo kuye kwabaluleka,” utshilo uRaha. Ngenxa yokuba ukuthotywa kwe-DELLA elawulwa yi-InsP₈ kunokuxhaphaka kwizityalo ze-embryonic, oku kufunyenweyo kunokuvula indlela yophuhliso lwesizukulwana esilandelayo sezityalo ezivelisa isivuno esiphezulu.
Ixesha lokuposa: Oct-31-2025