Chloroplasts na algae da tsire-tsire su ne injinan salula waɗanda ke canza makamashin hasken rana zuwa makamashin sinadarai ta hanyar photosynthesis. Waɗannan gabobin, waɗanda ke daure da ambulaf mai maɓalli biyu, suna ɗauke da nasu kwayoyin halittar da yanayin yanayin su ya daidaita sosai da na kwayoyin halittar nukiliya. Mafi yawan sunadaran chloroplast ana yin su ne ta hanyar kwayoyin halittar nukiliya, wanda aka fassara a cikin cytosol a matsayin sunadaran da ke ƙunshe da tsarin wucewa a ƙarshen amino ɗin su wanda ke aiki azaman tikitin shiga cikin chloroplasts.
Shigo da furotin a cikin chloroplast yana yin sulhu ta hanyar hadaddun furotin membrane guda biyu da ake kira TOC da TIC a cikin membrane na waje da na ciki, bi da bi. Waɗannan rukunin gidaje suna taka muhimmiyar rawa a ciki chloroplast biogenesis, a cikin taron na'urorin photosythetic da kuma a cikin hanyoyi daban-daban na rayuwa. An gano nau'ikan furotin daban-daban na TOC da TIC kuma an bayyana su, kuma an bayyana TOC da TIC don samar da babban hadaddun tare. Koyaya, yadda furotin daban-daban na TOC da TIC ke haɗuwa tare don samar da tashoshi don canza furotin a cikin ambulan chloroplast ba a sani ba, kuma hanyoyin canza furotin a cikin TOC da TIC sun kasance da wuya.
A wani binciken da aka buga a yanar gizo a Nature, Kungiyar Liu Zhenfeng ta kwalejin nazarin halittu ta kwalejin kimiyya ta kasar Sin, tare da hadin gwiwar farfesa Jean-David Rochaix na jami'ar Geneva ta kasar Switzerland, sun ba da hangen nesa da aka dade ana jira game da sassan kwayoyin halitta, da tsarin tsari guda uku da kuma yiwuwar gina jiki. hanyoyin juyawa na TOC-TIC supercomplex daga koren alga mai cell guda ɗaya mai suna Chlamydomonas reinhardtii.
Masu binciken sun ba da haske game da gine-ginen supramolecular na TOC-TIC supercomplex ta hanyar microscopy-electron microscopy.
An gano nau'ikan furotin guda goma sha uku daban-daban a cikin wannan supercomplex. Ban da Tic214 da ke tattare da kwayoyin halittar chloroplast, duk sauran sassan da ke cikin rukunan nukiliya. An tattara su a cikin hadaddun TOC a cikin membrane na waje, hadadden sararin samaniya (ISC) da hadaddun TIC a cikin membrane na ciki. Abin sha'awa, an gano cewa mafi girman sunadaran membrane Tic214 ya mamaye membrane na ciki, sararin intermembrane da membrane na waje, yana haɗa ɗayan. furotin ƙananan abubuwa kamar gada kuma mai yuwuwa kuma suna aiki azaman abin zamba.
Ƙungiyar TOC a cikin membrane na waje ya ƙunshi Toc34, Toc90 da Toc75, wanda ke gefen Toc90 ta hanyar Ctap4-Ctap3. A matasan ganga mai siffa channel An kafa ta Toc90 da Toc75 akan membrane na waje. Tashar tana ƙunshe da wata mashiga a gefen cytosolic da kuma fita guda biyu masu buɗewa zuwa sararin intermembrane, da kuma ƙofar gefe da ke fuskantar lipid bilayer. A phytic acid (wanda kuma aka sani da inositol hexaphosphate/InsP6) kwayoyin halitta yana shiga tsaka-tsakin tsaka-tsaki tsakanin Toc90 da Tic214, yana daidaita taron su kamar tsinke.
Yankin intermembrane-sarari na Tic214, Tic100, Tic56, Ctap3 da Ctap5 sun haɗu da juna don samar da tsari mai kama da hasumiya mai haɗa TOC tare da TIC. A cikin membrane na ciki, Yankunan da ke cikin membrane na Tic214, Tic20, Ctap5 da ƙananan ƙananan ƙananan guda uku (mai suna Simp1, Simp2 da Simp3) sun samar da hadaddun TIC. Kwayoyin lipid guda huɗu suna aiki don daidaita haɗuwar tashar mai kama da mazurari da ke a mahaɗin tsakanin Tic214 da Tic20 kuma suna hana tashar daga yabo.
Dangane da bayanan tsarin, masu binciken sun yi nazari dalla-dalla dalla-dalla fasali na pores a cikin tashoshin TOC da TIC. Sun sami damar yin hasashen hulɗar tsakanin peptide na wucewa da kuma hadaddun TIC ta hanyar kwaikwaiyon motsin kwayoyin halitta.
Taimakawa ta hanyar lura da ramukan tashoshi guda biyu da aka haɗa ta hanyar tsagi da kuma bayanan biochemical da na aiki na baya, an ba da shawarar hanyoyin da yawa don yin la'akari da jujjuyawar preproteins daban-daban ta hanyar TOC-TIC supercomplex zuwa keɓaɓɓen sassan chloroplast na gida.