Nucleolar ọrụ na cell ihe? The nucleolus: Ọdịdị na ọrụ

The cell bụ isi unit nke ndu eme ntule na Earth, na nwere a mgbagwoju chemical nzukọ owuwu akpọ organelles. Ndị a gụnyere ntọala, ihe owuwu ma na ọrụ nke anyị ga inyocha a n'isiokwu a.

Akụkụ nke eukaryotic nuclei

Nucleated mkpụrụ ndụ ya mejupụtara nwere ndị na-abụghị akpụkpọ ahụ organelles mechie, thicker karịa karyoplasm na-akpọ nucleolus ma ọ bụ nucleoli. Ha e chọpụtara na narị afọ nke 19. Ugbu a nucleoli zuru ezu na-amụ site elektrọn Microscopy. Fọrọ nke nta ruo mgbe 50s nke narị afọ nke 20 nucleolar ọrụ na e kwuru na ọ bụ, na ndị ọkà mmụta sayensị na-atụle nke a organelle, kama, dị ka a na-esite nke mapụtara bekee eji n'oge mitosis.

Modern nnyocha ike na organoid agụnye nsogbu dị iche iche nucleoprotein okike. Ọzọkwa, Biochemical nwere enen na organelle mejupụtara a ọnụ ọgụgụ buru ibu nke na-edozi. Na ha ime ka ya elu njupụta. Ọzọkwa proteids, nucleoli ugbu a na ihe ndị mejupụtara a obere ego nke RNA na DNA.

cell okirikiri

-Akpali mmasị, na ndụ nke cell, nke bụ a izu ike oge (interphase) na nkewa (meiosis - mmekọahụ, mitosis - na somatic cell), nucleoli echekwara mgbe nile. Ya mere, na interphase ntọala na nucleolus, nke na-arụ ọrụ - ichebe nke genome na guzobe nke protein-synthesizing organelles bụ ugbu bụchaghị. Ná mmalite nke cell nkewa, ya bụ prophase, ha na-apụ n'anya na re-kpụrụ naanị na njedebe nke telophase, debere a onu ruo mgbe ọzọ nkewa ma ọ bụ ka apoptosis - mbibi ya.

nucleolus nhazi

Na 30s nke ikpeazụ nke narị afọ, ndị ọkà mmụta sayensị achọpụtala na e guzobere nucleoli na-achịkwa ụfọdụ ngalaba nke ụfọdụ chromosomes. Ha na-ebu mkpụrụ ndụ ihe nketa, nke na-echekwa ihe ọmụma banyere ihe owuwu ma na-ihe bụ ọrụ nke nucleolus na cell. E nwere a mmekọrịta dị n'etiti na nke ukwu nke nucleolar nhazi na organelles onwe ha. Ka ihe atụ, African clawed frog na e dere n'ime ya karyotype abụọ nucleolus chromosome ma si otú na nuclei nke somatic mkpụrụ ndụ ọ bụ abụọ nucleoli.

Ebe ọ bụ na nucleolus ọrụ nakwa dị ka ọnụnọ a na-akpachi anya na cell nkewa na guzobe ribosomes, na organelles onwe ha kọrọ ukwuu pụrụ iche ụbụrụ anụ ahụ, ọbara, ma na zaigọtụ blastomeres Mace.

amplification nke nucleoli

The sịntetik nzọụkwụ interphase tinyere DNA replication onwe-ibawanye emee ngafe nke rRNA mkpụrụ ndụ ihe nketa. Ebe ọ bụ na isi ọrụ nke nucleolus - mmepụta nke ribosomes, na njikọ na overexpression nke loci DNA na-ebu ozi banyere RNA n'ike n'ike mụbara ọnụ ọgụgụ nke ndị a organelles. Nucleoproteins, ọ bụghị metụtara na chromosomes-ebido rụwa ọrụ autonomously. N'ihi - a plurality nucleoli na ntọala kpụrụ, ịgbara ya si nucleolar chromosomes. Nke a na onu na-akpọ amplification nke rRNA mkpụrụ ndụ ihe nketa. N'ịnọgide na-amụ ọrụ nke nucleolus na cell, anyị mara na ihe kasị ike nke njikọ n'akparamagwa meiotic prophase nke meiosis, adịru mbụ iji oocytes nwere ike ịnwe ọtụtụ narị nucleoli.

The ndu nke a pụtara onu na-aghọ doro anya mgbe ị na-atụle na ná mmalite nkebi nke embryogenesis: ndinuak na blastulation, mkpa a nnukwu ego nke ribosomes synthesizing isi ụlọ onwunwe - protein. Amplification - pụtara nkịtị usoro, ọ na-ewe ebe ke oogenesis nke osisi, ụmụ ahụhụ, amphibians, yist, na ụfọdụ protists.

Histochemical mejupụtara organelles

Anyị na-anọgide na-amụ ihe nke eukaryotic mkpụrụ ndụ na ha akụkụ, na tụlee nucleolus, Ọdịdị na ọrụ nke na-oyiri. Ọ na-hụrụ na ọ na e dere atọ ụdị ọcha:

1. Nukleonemy (aji guzobere). Ha bụ heterogeneous ma nwere fibrils na lumps. Dị ka akụkụ nke ma osisi na anụmanụ mkpụrụ ndụ, nukleonemy ụdị fibrillar emmepe. Cytochemical Ọdịdị na ọrụ nke nucleolus bụkwa dabere na ọnụnọ nime ya nke matriks - a netwọk nke akwụkwọ protein tertiary Ọdịdị nke ahụ ụmụ irighiri.
2. Vacuoles (ẹkenemede).
3. Granular pellets (nucleolin).

Si echiche chemical analysis, na organoid mejupụtara fọrọ nke nta kpamkpam nke RNA na protein na DNA bụ naanị na ya mpụta, akpụ ihe annular Ọdịdị - okoloyadryshkovy chromatin.

Ya mere, anyị nwere ike na Ọdịdị nke ahụ nucleolus emi esịnede ise entities: na granular na fibrillar emmepe, chromatin, na protein reticulum n'oké fibrillar akụrụngwa.

ụdị nucleoli

Biochemical Ọdịdị nke ndị a organelles na-adabere na cell ụdị nke ha dị ugbu a, nakwa dị ka e ji mara ha metabolism. Ịmata Ọdịiche 5 ụdị isi bughi nucleoli. Mmalite - reticular, ọtụtụ nkịtị na e ji ihe n'ụba nke oké fibrillar ihe clumps na nucleoproteins nucleons. The usoro nke rewriting ọmụma nucleolar nhazi bụ nnọọ ọrụ, otú ahụ fibrillar emmepe na-agụghị oké anya n'okpuru mikroskopu.

Ebe ọ bụ na isi ọrụ nke nucleolus na cell - njikọ nke ribosomal subunits, nke nke na-etolite protein-synthesizing organelles, na reticular ụdị nzukọ pụta ụwa ma osisi na ụmụ anụmanụ mkpụrụ ndụ. Nucleoli annular ụdị pụtara na connective anụ ahụ na mkpụrụ ndụ: lymphocytes na endothelial mkpụrụ ndụ, onye mkpụrụ ndụ ihe nketa na-transcribed rRNA fọrọ. Mmapụta nucleoli na-hụrụ na mkpụrụ ndụ kpamkpam furu efu ike transcription ihe atụ, normoblasts na enterocytes.

Segregated ụdị pụta ụwa mkpụrụ ndụ nwetara mmenaanya carcinogens, ọgwụ nje. N'ikpeazụ, a kọmpat ụdị nucleolar fibrillar emmepe ji a set na a ole na ole nke nucleons.

Nucleolar protein matriks

Anyị na-anọgide na-amụ ihe nke esịtidem Ọdịdị nke ahụ kernel owuwu ma na-ekpebi ihe bụ ọrụ nke nucleolus na cell metabolism. Ọ maara na ihe 60% site na akọrọ arọ dara na a organelle edozi na-eme ka chromatin, ribosomal ahụ, nakwa dị ka ihe kwesịrị ekwesị nucleolar edozi. Ka anyị tụlee ha n'ụzọ zuru ezu. Part nke proteids bụ idem ke nhazi - guzobe tozuru okè ribosomal RNA. Ndị a gụnyere RNA polymerase 1 na nuclease na wepu ngafe triplets na niile rRNA ụmụ irighiri. Protein fibrillarin dị na oké fibrillar akụrụngwa na, dị ka nuclease na anamde nhazi. Ọzọ protein - nucleolin. Ọnụ na fibrillarin ọ bụ na ndị PFC na FC nucleoli na nucleolar nhazi chromosome prophase nke mitosis.

Dị otú ahụ polypeptide ka nukleofozin dị na granular mpaghara na a na ok fibrillar akụrụngwa, ọ atụ ke guzobere ribosomal 40 S 60 S subunits.

Nso ke nucleolus

Njikọ nke ribosomal RNA - na isi ọrụ nke bụ ịrụ nucleoli. N'oge a, na ya elu (i.e. na fibrillar emmepe) emee transcription site enzyme RNA polymerase. Mgbe a na nucleolar nhazi synthesized narị tupu ribosomes ribonucleoprotein akpọ globules. Of ndị kpụrụ ribosomal subunits na site na nuclear pores na-ahapụ karyoplasm onwe-ha na cell cytoplasm. The obere subunit 40s na jikọọ na ozi RNA, na nanị mgbe na nnukwu subunit 40s bụ mmasị na ha. Image nke a tozuru okè ribosome ike ka ohuru - njikọ nke cellular-edozi.

N'isiokwu a anyị na-nucleolar Ọdịdị na ọrụ e mụọ na osisi na ụmụ anụmanụ mkpụrụ ndụ.