Gịnị bụ polysomes. Ọdịdị nke iwu prokaryotes na eukaryotes

Protein njikọ - ọ bụ a dị mkpa ndu usoro na pụtara na mkpụrụ ndụ nke ọ bụla organism. Ndi na-edozi bụ isi na klas nke organic bekee mkpụrụ ndụ, igosi a dịgasị iche iche nke ọrụ, na-amalite na-agwụcha na a na-echebe enzyme. Gịnị bụ polysomes? Dị ka nke a Ọdịdị na-eji na protein njikọ?

Gịnị bụ polysomes

Na mkpụrụ ndụ nke eukaryotes na prokaryotes bụ adịgide adịgide owuwu nke ribosome. Nke a obere corpuscles, esịnede abụọ subunits na ndị ọrụ nke na-arụ protein njikọ na translation usoro. Ribosome - a na-abụghị ndị akpụkpọ ahụ Ọdịdị.

Polysomes - a kpụworo esịnede ọtụtụ ribosomes. Ha na-ekwurịta okwu ọ bụla ọzọ site na matriks ma ọ bụ ozi RNA. Ọtụtụ ribosomes, dị ka chaplet, na-etinye on a molekul dapụtara na temporal Ọdịdị - polysomes.

Polysomes mkpụrụ ndụ na-lekwasị ebe dị mkpa ngwa ngwa njikọ nke buru ibu nke na-edozi. Nke a bụ isi ndu ọrụ nke ndị a entities.

Ọdịdị nke ahụ ribosome

T. k. Polis etolite ọtụtụ yiri ribosomes, i kwesịrị ịtụle ihe owuwu nke ikpeazụ.

Ọ bụla cell ribosome mejupụtara abụọ subunits, nnukwu na obere. N'etiti ha na-kpụrụ a obere ọdịiche n'obosara adabara nkenke na mRNA molekul nke e kwesịrị.

Ribosomes bụ mgbagwoju nucleoprotein okụre, ie. K. A akụkụ nke ma obere na nnukwu subunit ribosomal RNA ụmụ irighiri na-agụnye na-edozi na. Ndi na-edozi na-arụ ọrụ nke ozu, na RNA nke nwere ribozyme (fermentative) ọrụ, na-eji na translation usoro.

Ọdịiche dị n'etiti prokaryotic na eukaryotic ribosomes

. Ebe ọ bụ na prokaryotes na eukaryotes - ha abụọ dị iche iche iche iche nke ntule, ha nwere iche dị na ribosomes, ya mere iwu, kwa.

Na prokaryotes, na cytoplasm bụ a nnukwu ego nke 70s ribosomes (S - sedimentation bụ mgbe niile, nke na-egosi na ọnụego nke deposition nke ahụ na a centrifuge). Ha na-guzobere site nnukwu subunit 50s na 30s obere subunit. Ọdịdị nke ahụ nnukwu subunit na prokaryotes gụnyere 5S na 23S RNA. N'aka nke ya, na obere subunit 16s RNA a kpụrụ.

Na nje na mkpụrụ ndụ kpụrụ a otutu polysomes. Nke a bụ n'ihi na eziokwu na ha nwere protein njikọ usoro dị nnọọ ngwa ngwa: na agbasa ozi n'ikuku na-amalite tupu ọgwụgwụ nke transcription usoro. N'ihi otu ihe ahụ, ịta nke ribosomes na cell bụ kasị nso nucleoid.

Na eukaryotes, e nwere iche dị na ụkpụrụ nke mgbe nile na-ọcha nke ribosome sedimentation. N'ihi ya, ọ bara uru bụ 80 maka nnukwu na obere subunits - 60 na nke 40 karị. Dị ka akụkụ nke nnukwu subunit e kewapụrụ 5S, 28S na 5,8S RNA, na obere - 18S RNA.

Na na prokaryotes na eukaryotes polysomes mee ngwangwa usoro nke protein njikọ. Nke a bụ nnọọ mkpa mgbe ị kwesịrị ngwa ngwa guzobere mbipụta nke protein ụmụ irighiri. The elu nke njikọ karịsịa e ji mara maka bacteria, ie. K. ozi RNA ha n'ebe ahụ a obere oge, na n'oge a na nkeji synthesize dị ka ukwuu nke na protein ụmụ irighiri. Nke ahụ bụ ihe polysomes na usoro ndu.

Translation usoro - isi ọrụ nke polysomes

N'oge translation kpụrụ isi Ọdịdị nke ahụ protein molekul. E nwere ihe atọ nke njikọ nke polypeptides: nnabata, elongation na nchupu.

1. mmalite nke translation. MRNA molekul ga-mmasị ka 16s RNA nke ụkpụrụ nke complementarity. N'ihi nke a, e nwere a pụrụ iche usoro na prokaryotes akpọ ribosomsvyazyvayuschim saịtị na eukaryotes - capped. Ya mere, ozi RNA bụ mmasị na obere subunit nke ribosome.

2. elongation. A na ogbo e ji buildup nke polypeptide yinye. Transportation RNA-eweta ribosome amino asịd, nke na-ejikọrọ na circuit kpụrụ peptide agbụ. N'ihi ya, protein njikọ ewe ebe ruo mgbe oge mgbe ọ na-akụrisị a ribosome stop codon.

3. nchupu. Ozugbo o ruru nkwụsị codon nke protein njikọ na-kwụsị. a guzobere ọhụrụ polypeptide si ribosome dara molekul site a pụrụ iche ọrịa strok, na mgbe ahụ na-aga guzobe sekọndrị, tertiary ma ọ bụ quaternary Ọdịdị.

Ribosome àgwà - usoro nke na-amụ ribosome

Ịmụta ihe polysomes, ị ga-họrọ ihe owuwu nke mkpụrụ ndụ nke ahụ. Ihe kacha ụzọ ime nnyocha na prokaryotic mkpụrụ ndụ. Ribosomal àgwà na-agụnye ndị na-esonụ:

1. The mbibi nke ndị na prokaryotic cell. Ọ dị mkpa ka mbibi a ga-rụrụ site n'ibu ụzọ, ie. A. Chemicals nwere ike imebi ribosomes onwe ha.

2. The cleavage nke RNA, nke na-adịghị ribosomal.

3. The otu ụkpụrụ na-rụrụ wepụ enweghị isi polypeptides nke ndị akụkụ nke ihe owuwu.

4. Reverse transcription nke ribosomal RNA dịpụrụ adịpụ.

5. Sekvernirovanie nwetara DNA.

ọgwụgwụ

Polysomes - a Ọdịdị na-kpụrụ nke ọtụtụ ribosomes. Ya ozi bụ iji mee ngwangwa njikọ nke na-edozi. Ndị a owuwu na-hụrụ na mkpụrụ ndụ nke prokaryotes na eukaryotes, Otú ọ dị ha ji mara nke mkpụrụ ndụ nke ọ bụla organism. Nke ahụ bụ ihe polysomes.