Ntchito nucleolar muchipindachi chiyani? The nucleolus: kapangidwe ndi ntchito

Selo ndi unit yaikulu ya zamoyo padziko lapansi ndipo ali ndi zovuta mankhwala gulu nyumba otchedwa organelles. Zikuphatikizapo phata, kapangidwe ndi ntchito umene ife kufufuza m'nkhani ino.

Features a mtima eukaryotic

maselo Nucleated mu kapangidwe kake lili sanali Kakhungu organelles adzakhale chachikulu kuposa karyoplasm ndipo anaitana nucleolus kapena nucleoli. Iwo anapeza m'nthawi ya 19. Tsopano nucleoli mokwanira anaphunzira kupyolera elekitironi wamamamayikirosikopu. Pafupifupi mpaka 50s wa ntchito nucleolar m'ma 20 sizinachitike kuzindikiridwa ndi asayansi ankaona organelle ili, kani, monga mosungiramo zinthu yopuma ntchito pa mitosis.

Akatswiri ofufuza wasonyeza kuti organoid zikuphatikizapo granules nucleoprotein chikhalidwe. Komanso zatsopano amuzolengedwa anatsimikizira kuti organelle zizindikiro zambiri zomanga thupi. Kuti iwo chifukwa kachulukidwe ake okwezeka. Komanso proteids, nucleoli alipo zikuchokera pang'ono RNA ndi DNA.

selo mkombero

N'zochititsa chidwi kuti moyo wa khungu, chomwe nthawi mpumulo (interphase) ndi kugawikana (meiosis - kugonana, mitosis - ndi somatic khungu), nucleoli kusungidwa zonse. Choncho, mu interphase phata ndi nucleolus, amene liziyenda - kuteteza matupi athu ndi mapangidwe a organelles mapuloteni-synthesizing alipo kwenikweni. Pa chiyambi cha kugawikana selo, ndicho prophase, iwo kutha ndi kukonzanso atangotha kumapeto kwa telophase, akusungidwa mu khola mpaka gulu lotsatira kapena aputosisi - uwonongedwe.

nucleolus kulinganiza

Mu 30s Mu zaka zapitazo, asayansi apeza kuti mapangidwe nucleoli umalamulidwa ndi zigawo zina DNA ena. Iwo ali majini, zimene zimasunga zokhudza zimene dongosolo ndipo kodi ntchito za nucleolus mchipindamo. Pali malumikizanidwe pakati pa kuchuluka kwa kulinganiza nucleolar ndi organelles okha. Mwachitsanzo, African clawed chule lili ake karyotype awiri nucleolus khromozomu ndipo motero mu mtima maselo somatic ndi nucleoli awiri.

Popeza ntchito nucleolus komanso kupezeka kwake chimakhudzana ndi kugawikana selo ndi mapangidwe ribosomes, ndi organelles okha akusowa apadera kwambiri ubongo minofu, magazi, ndi zygote blastomeres Mace.

amveke wa nucleoli

Chinthu kupanga interphase pamodzi ndi DNA kugawanika kudziletsa anawaonjezera kuwirikiza kawiri amapezeka owonjezera rRNA chibadwa. Popeza Ntchito yaikulu ya nucleolus - yopanga ribosomes, mogwirizana ndi overexpression wa loci DNA kuti kunyamula zokhudza RNA ndi kwambiri chinawonjezeka chiwerengero cha organelles izi. Nucleoproteins, kumphatikiza ndi DNA kuyamba kugwirira ntchito autonomously. Chifukwa cha - ndi kuchuluka nucleoli mu phata kupangidwa, distancing lokha kuchokera DNA nucleolar. zodabwitsazi amatchedwa amveke wa rRNA chibadwa. Kupitiriza kuphunzira ntchito ya nucleolus muchipindachi, tiona kuti yogwira ambiri kaphatikizidwe amapezeka meiotic prophase wa meiosis, umene woyamba kuti oocytes anyamula nucleoli mazana angapo.

Tanthauzo zamoyo zodabwitsazi zimaonekeratu Mukaganizira kuti mu magawo oyambirira embryogenesis: onongani ndi blastulation, muyenera kuchuluka yaikulu ribosomes synthesizing nkhani yaikulu yomanga - mapuloteni. Amveke - zofala ndondomeko, izo zikuchitika mu oogenesis ya zomera, tizilombo, achule, yisiti ndi ena protists.

Histochemical zikuchokera organelles

Tipitirize kuphunzira za maselo eukaryotic ndi nyumba zawo, ndi kukambirana nucleolus, kapangidwe ndi ntchito zimene ndi zogwirizana. Umapezeka kuti muli mitundu itatu ya zinthu:

1. Nukleonemy (ndevu mapangidwe). Iwo sakanikira ndipo muli fibrils ndipo apezeka. Monga mbali ya onse zomera ndi nyama maselo, nukleonemy malo mawonekedwe fibrillar. Cytochemical kapangidwe ndi ntchito ya nucleolus ndilo amadalira pamaso m'menemo ya masanjidwewo - zopezera Buku mapuloteni ukachenjede kapangidwe ka tinthu lapansi.
2. Vacuoles (zazikulu).
3. pellets Granular (nucleolin).

Ku maganizo a kuwunika mankhwala, ndi organoid Amakhala pafupi kwathunthu kwa RNA ndi mapuloteni ndi DNA ndi kokha pa periphery ake, musayambe annular kapangidwe - okoloyadryshkovy chromatin.

Kotero ife anakhazikitsa kuti kapangidwe ka nucleolus ndi wapangidwa ndi mabungwe asanu: ndi granular ndi fibrillar malo, chromatin, mapuloteni reticulum ndi wandiweyani fibrillar chigawo.

mitundu ya nucleoli

Amuzolengedwa Kapangidwe ka organelles izi zidalira pa mtundu selo imene alipo, komanso makhalidwe a kagayidwe awo. Kusiyanitsa mitundu 5 nucleoli zofunika structural. Origin - reticular, ambiri ndipo amakhala ndi chochuluka wandiweyani clumps fibrillar zakuthupi ndi nucleoproteins nucleons. The ndondomeko ya rewriting mudziwe nucleolar kulinganiza ndi wotanganidwa kwambiri, kotero madera fibrillar ndi bwino kuonekera pa maso pa.

Popeza Ntchito yaikulu ya nucleolus selo - kaphatikizidwe wa subunits ribosomal, amene apanga organelles mapuloteni-synthesizing, mtundu reticular gulu la chibadidwe zomera ndi nyama maselo onse. Nucleoli annular mtundu amapezeka maselo connective minofu: lymphocytes ndi maselo za indofeliyamu, amene majini ndi wolembedwa rRNA mwakuchitika. nucleoli yotsalira zimapezeka maselo kwathunthu anataya luso galamafoniyo Mwachitsanzo, normoblasts ndi enterocytes.

mtundu popeleka ma maselo chibadidwe aona kuledzera carcinogens, mankhwala. Pomaliza, mtundu yaying'ono malo nucleolar fibrillar yodziwika ndi akonzedwa ndi ochepa nucleons.

Nucleolar mapuloteni masanjidwewo

Tipitirize kuphunzira dongosolo mkati mwa nyumba ngale ndipo pezani ndi ntchito za nucleolus mu kagayidwe selo. Amadziwika kuti pafupifupi 60% mwa kulemera youma imagwera pa izi mapuloteni organelle amene amapanga chromatin, particles ribosomal, komanso moyenera nucleolar mapuloteni. Tiyeni tione iwo mwatsatanetsatane. Part wa proteids ndi kulowerera processing - mapangidwe okhwima ribosomal RNA. Zikuphatikizapo RNA polymerase 1 ndi nuclease kuti kuchotsa atatu owonjezera ndi tinthu onse rRNA. Mapuloteni fibrillarin ili mu wandiweyani fibrillar chigawo ndipo, ngati nuclease ndi kukachita processing. Wina mapuloteni - nucleolin. Pamodzi ndi fibrillarin ndi mu PFC ndi FC nucleoli ndi nucleolar kulinganiza khromozomu prophase wa mitosis.

Chotero polypeptide monga nukleofozin ili mu zone granular ndi wandiweyani fibrillar chigawo, izo nawo mu mapangidwe ribosomal 40 S 60 S subunits.

Kodi nucleolus

Kaphatikizidwe wa RNA ribosomal - ntchito yaikulu imene ndi kuchita nucleoli. Panthawi imeneyi, pamwamba pake (i.e. mu malo fibrillar) limapezeka galamafoniyo ndi puloteni RNA polymerase. Pa kulinganiza izi nucleolar apanga mazana chisanadze ribosomes ribonucleoprotein otchedwa globules. Anthu anapanga subunits ribosomal kuti kudzera pores nyukiliya ndi kusiya karyoplasm okha ndi cytoplasm selo. Ang'ono kagawo kakang'ono 40S chikugwirizana kwa mtumiki RNA, ndipo patapita kuti lalikulu kagawo kakang'ono 40S ndi kuwakonda. Image wa ribosome okhwima angathe wailesi - kaphatikizidwe mapulotini ma.

M'nkhaniyi tiona nucleolar kapangidwe ndi ntchito anali kuphunzira mu zomera ndi nyama maselo.