Yintoni na polysomes. Ubume bale prokaryotes nkqubo kunye eukaryotes

Protein yokuqaphela - yinkqubo ebalulekileyo zebhayoloji ezehla iiseli nayiphi ephilayo. Proteni kwiklasi ephambili kwezinto iiseli eziphilayo, yenza uluhlu olubanzi lwemisebenzi, ekuqaleni nasekupheleni kohambo kunye enzayim olukhuselayo. Yintoni polysomes? Njengoko esi sakhiwo isetyenziswa kakhulu ngakwicala leeprothini yokuqaphela?

Yintoni polysomes

Xa iiseli eukaryotes kunye prokaryotes ayizozakhiwo ezibophelelayo le ribosome. Oku corpuscles ezincinane, ezibandakanya subunits ezimbini umsebenzi ukwenza protein kudibaniso kwinkqubo translation. Ribosome - isakhiwo non-ndizayo.

Polysomes - ukuma eliquka ribosomes eziliqela. Ethetha nabanye nge isizalo okanye umthunywa RNA. ribosomes eziliqela, ezifana amaso, ibekwe kule molecule kubangele kwisakhiwo zexeshana - polysomes.

iiseli Polysomes bebekelwa apho kuyimfuneko kuyondelelaniswe ngokukhawuleza oluninzi iiprothini. Le indima ephambili ngokobugcisa kula maqumrhu.

Ubume ribosome

T. k. Polis zibe ribosomes ezininzi ezinxulumene, kufuneka ucinge isakhiwo yokugqibela.

Nayiphi ribosome iseli iqulathe subunits amabini, ezinkulu nezincinane. Phakathi kwabo abunjwe enobubanzi isikhewu encinane ezifanelekileyo ngqo kwi kwemolekyuli mRNA apho apho kufuneka.

Ribosomes kukho izakhiwo nucleoprotein ezintsonkothileyo, okt. K. A inxalenye Ezincinane ezinkulu iimolekyuli enganeno ribosomal RNA ziquka iiprothini kunye. Neeproteni enze umsebenzi isidumbu, yaye RNA leyo ilifa ribozyme umsebenzi (fermentative), ezisetyenziswa kwinkqubo translation.

Umahluko phakathi ribosomes prokaryotic kunye eukaryotic

. Ekubeni prokaryotes kunye eukaryotes - bona amaqela ezahlukeneyo ezimbini eziphilayo, babe iiyantlukwano kwiqela le ribosomes, ngoko mgaqo-nkqubo, kananjalo.

Xa prokaryotes, ukuba kukho icytoplasm na isixa esikhulu 70s ribosomes (S - neentlenge njalo, nto leyo ebonisa izinga yokulahlwa kwe-amasuntswana icentrifuge). Bona akhiwa enganeno 50 ezinkulu 30 enganeno amancinci. Ubume enganeno elikhulu prokaryotes ziquka 5 kunye 23S RNA. Ngenxa yoko, le enganeno encinane 16S RNA yenziwe.

Xa iiseli bacteria bakha oluninzi polysomes. Oku kungenxa yokuba babe inkqubo yokuqaphela iproteni ikhawuleza kakhulu: zosasazo iqala phambi kokuphela kwenkqubo tumbuluxiwa. Ngenxa yesizathu esifanayo, uyazikhomba ribosomes kwi iseli yeyona inkulu kufutshane nucleoid.

Xa eukaryotes, kukho umahluko amaxabiso eziqalelo lomgadi neentlenge ribosome. Ngokuba, ixabiso le-80 ngenxa subunits ezinkulu nezincinane - 60 no-40 ngokulandelelanayo. 5 Njengenxalenye enganeno enkulu eyedwa, 28 kunye 5,8S RNA, yaye ezincinane - 18s RNA.

Kwaye prokaryotes kunye eukaryotes polysomes ukukhawulezisa inkqubo protein yokuqaphela. Oku kubaluleke kakhulu xa ufuna ukwakheka ngokukhawuleza iikopi zeprotheyini neemolekyuli. Izinga eliphezulu kuyondelelaniswe ingakumbi uphawu lwegciwane, okt. K. Messenger RNA kubo apho ixesha elifutshane, yaye ngeli xesha lokuphumla ukuze nokulungelelanisa kangangoko ezo molekyuli protein. Nantso into polysomes eziphilayo.

inkqubo Translation - nguwona msebenzi polysomes

Ngexesha translation kwakhiwa isakhiwo ephambili molecule protini. Kukho amanyathelo amathathu Yindibanisela polypeptides: yolwaluko, zobude kunye nokupheliswa.

1. Ukuqaliswa translation. MRNA molecule kufuneka iqhotyoshelwe 16S RNA ye -siseko complementarity. Ukulungiselela le njongo, kukho ulandelelwano eyodwa prokaryotes ngokuba isiza ribosomsvyazyvayuschim kunye eukaryotes - eliswenyiweyo. Ngoko ke, isithunywa RNA encamathele enganeno encinane le ribosome.

2. zobude. Eli nqanaba libizwa luphawulwa elibi chain polypeptide. Zokuhamba RNA uzise le asidi ribosome acid, abaqhagamshelwe wesekethe lisekwa kwiintambo peptide. Ngenxa yoko, Iprothini kuyondelelaniswe kwenzeka kude kube mzuzu xa ibetheke codon ribosome stop.

3. Ukupheliswa. Xa sele ufikelele codon stop le njini iproteni luyekisiwe. a polypeptide omtsha ukusuka ribosome iwela molecule ngokusebenzisa stroke ekhethekileyo, aze emva koko idlule ukuyilwa kobume lesibini, emfundo ephakamileyo okanye koqeqesho.

iiprofayili Ribosome - indlela ukufunda ribosome

Ukuze ufunde oko polysomes, umele ukhethe isakhiwo iiseli zomzimba. Indlela elula yokwenza uphando iiseli prokaryotic. iiprofayili Ribosomal kubandakanya le manyathelo alandelayo:

1. Ukutshatyalaliswa iseli prokaryotic. Kubalulekile ukuba intshabalalo kufuneka kwenziwa ngomatshini, okt. A. Chemicals zingonakalisa ribosomes ngokwabo.

2. Le cleavage RNA, izinto ezo ribosomal.

3. Lo mgaqo mnye ikhutshwa ekususeni polypeptides ezingeyomfuneko angeyonxenye eso sakhiwo.

4. Ukuloba reverse ribosomal RNA ekude.

5. Sekvernirovanie wafumana DNA.

isiphelo

Polysomes - isakhiwo ezikhandelwa of ribosomes eziliqela. Umnqophiso walo ukukhawulezisa Yindibanisela iiprothini. Ezi zithinteli zifumaneka iiseli prokaryotes kunye eukaryotes, kodwa ke uphawu iiseli nayiphi ephilayo. Nantso into polysomes.