Kodi apanga rRNA. RRNA Ribosomal RNA: mapangidwe ndi malongosoledwe a dongosolo la

Maselo zamoyo akhala akuphunzira kapangidwe ndi ntchito ya mamolekyulu organic amene amapanga maselo a zomera, nyama ndi anthu. Lodziwika pakati pawo wapatsidwa gulu la mankhwala otchedwa mkati (nyukiliya) zidulo.

Pali mitundu iwiri: deoxyribonucleic acid (DNA) ndi ribonucleic. Yotsirizira ali zosintha zingapo: mRNA, tRNA ndi rRNA, amene amasiyana Ntchito yawo ndi malo kutanthauzira mchipindamo. Nkhaniyi khama kuphunzira mafunso otsatirawa: kumene apanga rRNA mu prokaryotic ndi maselo eukaryotic, kodi matabwa ake ndi tanthauzo.

nkhani za m'mbiri

Woyamba kutchulidwa sayansi asidi ribosomal angapezeke mu maphunziro ndi R. Weinberg ndi S. Penman 60-ntchentche wa XX atumwi, amene anafotokoza yochepa polynucleotide molekyulu zokhudzana RNA, koma osiyana okhudza malo kapangidwe ndi sedimentation koyefishienti mauthenga ndi kutengerapo RNA. Nthawi zambiri, mamolekyulu awo zimapezeka zikuchokera nucleolus, ndipo organelles selo - ribosomes, udindo kaphatikizidwe zomanga thupi yotere. Iwo ankatchedwa ribosomal (Ribosomal RNA).

Mapangidwe a RNA

asidi Ribonucleic, ngati DNA, ndi polima umene monomers ndi nucleotides mitundu 4: adenine, guanine, uracil ndi cytidine chikugwirizana nsinga phosphodiester mu mamolekyulu yaitali osakwatiwa-Shackleton, wopota mu mwauzimu kukhala zovuta zambiri kapena conformation. Palinso awiri Shackleton Ribosomal RNA kunachitika RNA mavairasi ndi kutsanzira ntchito DNA: kukhalabe ndi kufala kwa makhalidwe cholowa.

mitundu itatu zidulo muchipindachi nthawi zambiri ndi: bokosi kapena zambiri, RNA zoyendera Ribosomal RNA, kumene amagwira kwa amino zidulo, komanso asidi ribosomal, yomwe ili nucleolus ndi cytoplasm selo.

Ribosomal RNA pafupifupi 80% zidulo ribonucleic muchipindachi ndipo 60% ya unyinji wa ribosome - organelle, ma kaphatikizidwe mapuloteni. mitundu yonse pamwamba ndi apanga (wolembedwa) m'madera ena a DNA, majini izi RNA. Pa kaphatikizidwe molekyulu zinakhalira enzyme wapadera - RNA polymerase. Place mu khungu, kumene rRNA ndi apanga - ndi nucleolus, umene uli karyoplasm pachimake.

Nucleolus, ntchito ka kaphatikizidwe

Maselo, wotchedwa selo mkombero kusiyanitsa pakati pa magulu ake - interphase. Pa nthawi ino, phata selo matupi wandiweyani nyumba granular otchedwa nucleoli ndipo n'chofunika zikuluzikulu za maselo onse masamba ndi nyama bwino kuwoneka.

Mu zamoyo, chinapezeka kuti nucleoli ndi organelles kumene rRNA ndi apanga. zofufuza Komanso inachititsa kuti ziwalo anapeza cytology ya DNA selo imene majini ndi udindo kapangidwe ndi kaphatikizidwe zidulo ribosomal anapezeka. Iwo ankatchedwa nucleolar kulinganiza.

nucleolus kulinganiza

60-ntchentche za XX atumwi zamoyo anali maganizo kulinganiza nucleolus, ili pa malo a constriction sekondale 13, 14, 15, 21 ndi 22 awiriawiri DNA, ali mawonekedwe a malo limodzi. Akatswiri nawo kuphunzira khromozomu kuwonongeka, wotchedwa aberrations, apeza kuti nthawi kusiyana khromozomu pa malo constriction yachiwiri aumbike nucleoli pa aliyense wa ziwaloziwalo.

Choncho, zotsatirazi zikhoza anati: nucleolus kulinganiza tichipeza imodzi koma zingapo loci (majini) ndi udindo mapangidwe nucleolus. Ndi momwemo apanga rRNA Ribosomal RNA kupanga kagawo kakang'ono mapuloteni-synthesizing selo organelles - ribosomes.

Kodi ribosome?

Monga tanena kale, mitundu yonse zitatu zikuluzikulu zomwe RNA kulibe muchipindachi, kumene iwo apanga mu zina - DNA chibadwa. Chifukwa ribosomal RNA galamafoniyo mawonekedwe maofesi ndi mapuloteni - RNPs wa imene imagwiritsidwa mbali ya organelles m'tsogolo, otchedwa subunits. Kudzera pores mu Kakhungu nyukiliya mu cytoplasm, iwo kusuntha ndi kupanga dongosolo United m'menemo chikukhudza molekyulu ndi likupitirizabe RNA ndi t-RNA, wotchedwa polysomes.

Ribosome okha akhoza olekanitsidwa ndi zochita za ayoni kashiamu ndi kukhalapo mu mawonekedwe a subunits osiyana. N'zosiyana ndondomeko akupezeka zipinda za cytoplasm cell komwe njira yomasulira zimachitika - kusonkhana mamolekyulu mapuloteni ma. Selo yogwira intensively kwambiri loyenda m'menemo kagayidwe, m'pamenenso lili ribosomes. Mwachitsanzo, maselo mafupa, hepatocytes ndi anthu peresenti nyama yodziwika ndi ambiri organelles izi mkati cytoplasm lapansi.

Kodi majini ndi ndiyotengera rRNA?

Kuchokera pa zimene takambiranazi, kapangidwe, mitundu ndi ntchito ya rRNA majini zimadalira kulinganiza nucleolar. Iwo anakonza loci munali majini wolemba pulogalamu kwa RNA ribosomal. O. Miller, kuchita kafukufuku maselo ovogenesis zimachitikira, limagwirira anakhazikitsa ntchito kwa majini izi. Popeza iwo apanga mabuku a rRNA (otchedwa chachikulu transkriptanty) munali za 13h103 nucleotides ndi kukhala sedimentation koyefishienti wa 45 S. Ndiye, dera lino umachitika yakucha ndondomeko mathero mawonekedwe mamolekyulu atatu a tsa-RNA sedimentation koefishienti wa 5,8 S, 28 S, ndipo 18 S.

Limagwirira la mapangidwe tsa-RNA

Tikaonanso Miller zatsopano zomwe ankafufuza kaphatikizidwe RNA ribosomal ndipo anasonyeza kuti DNA akutumikira chitsanzo nucleolar (masanjidwewo) mapangidwe tsa-RNA - transkriptanta. Iye anapeza kuti kuchuluka kwa enzyme RNA polymerase mamolekyulu zimadalira chiwerengero cha zidulo mwana ribosomal (chisanadze rRNA), amene anapanga. Ndiye kusasitsa (processing), ndi tsa-RNA mamolekyulu anayamba nthawi yomweyo kumumanga kuti mapeputisayidi, ndi chifukwa ndi ribonucleoprotein - zomangila ribosome.

NKHANI ribosomal zidulo maselo eukaryotic

Kukhala mfundo ndi dongosolo la padziko lonse la asilikali zinchito za ribosomes prokaryotic ndi zamoyo nyukiliya asemphana tsitomolekulyarnye. Sanawapeze, ofufuza kuphunzira ntchito njira yotchedwa X-ray kusanthula. Anapeza kuti ukulu wa ribosome eukaryotic motero tsa-RNA m'gulu izo, ndi wamkulu sedimentation koyefishienti 80 S. organelle, kutaya mankhwala enaake a ayoni, akhoza anapatukana mu subunits awiri ndi zizindikiro 60 S ndi 40 S. Small tinthu limapangidwa kam'bulu kamodzi ka acid ndi lalikulu - atatu, i.e. nucleated maselo muli ribosomes, ongokhala 4 polynucleotide helices asidi zotsatirazi: 28 m RNA - 5 zikwi nucleotides, 18 m - 2 zikwi 5 m - 120 nucleotides, 5, .. 8 S - 160. Mbali kumene rRNA ndi apanga maselo eukaryotic - ndi disintegrations nucleolus chonyenga karyoplasm phata.

Ribosomal RNA prokaryotes

Mosiyana tsa-RNA mwa maselo nucleated, bakiteriya ribosomal zidulo ribonucleic ali wolembedwa pa gawo wothinikizidwa wa cytoplasm munali DNA ndipo anaitana nucleoid. Lili ndi rRNA chibadwa. Dongosolo, ndi khalidwe ambiri amene angagwiritsidwe ukufanizidwa ndi mfundo rewriting ndondomeko ndi chibadwa tsa-RNA mu ndondomeko ya ribosomal ribonucleic asidi nyukiliotayidi mapolojekiti DNA ndi malamulo a za malamulo opanga khalidwe: adenine nukleoitid limafanana uracil, ndi guanine - cytosine.

R-RNA mabakiteriya ndi m'munsi maselo kulemera ndi miyeso kakang'ono kuposa maselo nucleated. sedimentation awo koyefishienti S 70, ndi subunits awiri ndi zizindikiro 50 S ndi 30 S. The tinthu ang'onoang'ono lili kam'bulu kamodzi ka tsa-RNAs, ndi lalikulu - awiri.

Udindo wa chidulo ribonucleic pa kumasulira

Ntchito yaikulu ya rRNA ndi kupereka ndondomeko ya biosynthesis mapuloteni selo - ndi moyo. Ndi kokha pamaso pa ribosomes munali rRNA. Lunzitsani m'magulu, amanga kwa DNA mfundo kupanga malamulo. Kuti izo kuchokera pa cytoplasm maselo abwino zoyendera molekyulu ribosomal zidulo ribonucleic kubala amino zidulo, amene, kamodzi mu polysomes zinalumikizana pamodzi ndi nsinga peputayidi kupanga polima - mapuloteni. Iye ndi zofunika kwambiri organic maselo pawiri ntchito zambiri zofunika: zomangamanga zoyendera mphamvu, enzyme, chitetezo ndi ma siginalo.

Nkhaniyi kufufuza kapangidwe khalidwe ndi malongosoledwe a zidulo ribosomal mkati ndi biopolymers organic maselo a zomera, nyama ndi anthu.