Abashakashatsi bavumbuye uburyo bwo kugenzura poroteyine ya DELLA mu bimera.

Abashakashatsi bo mu Ishami rya Biochimie mu Kigo cy’Ubumenyi bw’Abahinde (IISc) bavumbuye uburyo bumaze igihe kirekire bukoreshwa n’ibimera byo ku butaka bya kera nka bryophytes (harimo mosses na liverworts) kugira ngokugenzura imikurire y'ibimera– uburyo bwakomeje kubikwa mu bimera bishya by’indabyo.

Ubushakashatsi bwasohotse mu kinyamakuru Nature Chemical Biology, bwibanze ku miterere idashingiye ku binyabuzima bya kera bya poroteyine ya DELLA, ikigo cy’ingenzi gishinzwe gukura gishobora kubuza igabanyuka ry’uturemangingo mu bimera biri mu nda (ibimera byo ku butaka).
“DELLA ikora nk'umuvuduko w'umuvuduko, ariko iyo uyu muvuduko w'umuvuduko uhora uhari, ikimera ntigishobora kugenda,” ibi ni ibyasobanuwe na Debabrata Laha, umwarimu wungirije wa biochimie akaba n'umwanditsi wungirije w'ubushakashatsi. Kubwibyo, kwangirika kwa poroteyine za DELLA ni ingenzi mu guteza imbere gukura kw'ibimera. Mu bimera bitanga indabyo, DELLA irangirika iyo phytohormonegibberellin (GA)Ifatana na receptor yayo GID1, igakora GA-GID1-DELLA complex. Nyuma yaho, poroteyine igabanya DELLA ifatana na ubiquitin chains hanyuma ikangirika na 26S proteasome.
Igishimishije ni uko bryophytes zari mu bimera bya mbere byagiye bizunguruka ku butaka, mu myaka igera kuri miliyoni 500 ishize. Nubwo zikora phytohormone gibberellin (GA), ntizifite receptor ya GID1. Ibi bitera ikibazo: ni gute imikurire n'iterambere ry'ibi bimera byo ku butaka byabanje byagenzurwaga?
Abashakashatsi bakoresheje sisitemu ya CRISPR-Cas9 kugira ngo bakureho gene ya VIH ijyanye nayo, bityo byemeza uruhare rwa VIH. Ibimera bidafite enzyme ya VIH ikora bigaragaza inenge zikomeye mu mikurire no mu mikurire ndetse n’imiterere mibi, nka dense thallus, imikurire mibi ya radial, no kubura calyx. Izi nenge zakosowe no guhindura genome y’ibimera kugira ngo habeho impera imwe gusa (N-terminus) ya enzyme ya VIH. Bakoresheje ubuhanga buhanitse bwa chromatography, itsinda ry’ubushakashatsi ryavumbuye ko N-terminus irimo domaine ya kinase itera imbaraga mu gukora InsP₈.
Abashakashatsi bavumbuye ko DELLA ari imwe mu ntego z'uturemangingo twa VIH kinase. Byongeye kandi, babonye ko imiterere y'ibimera bidafite MpVIH isa n'iy'ibimera bya Miscanthus multiforme hamwe n'ubwiyongere bwa DELLA.
“Kuri iki cyiciro, twifuza kumenya niba DELLA ihamye cyangwa imikorere yayo iri kwiyongera mu bimera bidafite MpVIH,” ibi byavuzwe na Priyanshi Rana, umunyeshuri w’itsinda ry’ubushakashatsi rya Lahey akaba n’umwanditsi wa mbere w’iyi nyandiko. Bikurikije igitekerezo cyabo, abashakashatsi basanze DELLA ibuza ibimera kongera gukura no gukura neza mu bimera bya MpVIH. Ibi byavumbuwe bigaragaza ko VIH kinase igenga nabi DELLA, bityo igateza imbere imikurire n’imikurire y’ibimera.
Abashakashatsi bahuje uburyo bwa genetiki, biokemike, na biofiziki kugira ngo basobanukirwe uburyo inositol pyrophosphate ikoresha mu kugenzura ikoreshwa rya poroteyine ya DELLA muri iyi bryophyte. By'umwihariko, InsP₈, ikorwa na MpVIH, ihuza na poroteyine ya MpDELLA, bigatuma polyubiquitination yayo iba nyinshi, ibyo bigatuma iyi poroteyine igabanya ubukana bw'ibinure iterwa na poroteyine.
Ubushakashatsi kuri poroteyine ya DELLA bwatangiye mu gihe cy’impinduramatwara y’ibidukikije, ubwo abahanga mu bya siyansi bakoreshaga ubushobozi bwayo batabizi mu gukora ubwoko bw’ibimera bitanga umusaruro mwinshi. Nubwo uburyo ikoramo butari buzwi icyo gihe, ikoranabuhanga rigezweho ryafashije abahanga mu bya siyansi gukoresha uburyo bwo guhindura ingirabuzimafatizo kugira ngo bahindure imikorere y’iyi poroteyine, bityo bikongera umusaruro w’ibihingwa.
Raha yagize ati: “Ubwo abaturage biyongera kandi ubutaka buhingwa bugagabanuka, umusaruro w’ibihingwa wiyongera cyane.” Bitewe n’uko kwangirika kwa DELLA mu buryo bwa InsP₈ bishobora gukwirakwira mu bimera bikiri mu nda, ubu buvumbuzi bushobora gutegurira inzira iterambere ry’ibihingwa bizatanga umusaruro mwinshi mu gihe kizaza.