Tangata katoa e tuatapapa i te koiora rāpoi, mataora, engineering ira, me te maha o te tahi atu mōhiotanga e pā ana, maoro,, ui te pātai: he aha te mea te mahi o te RNA polymerase? Ko tenei he kaupapa tika matatini e he tonu tino unexplored, engari, ahakoa, kua mohiotia ai e ka tahuna reira hei wāhanga o te tuhinga.
mōhiohio whānui
He mea tika ki te mahara e reira he RNA polymerase o eukaryotes me prokaryotes. Kei te wehea atu te tuatahi ki toru ngā momo, ia o nei te mea haepapa mo te patohanga o ira rōpū motuhake. E taua ēnei whākōkī mō te tapatahi, rite te tuatahi, te tuarua, me te tuatoru polymerase RNA. Prokaryotes, te hanganga o nei kore-karihi, ka tuhi mahi rite ki te hoahoa māmā. Na reira, mo te mārama, ki te hopu i rite nui ngā mōhiohio rite eukaryotes ka taea e tukinotia. Ko te hanganga rite polymerases RNA. Kei te whakapono te reira e kore i roto i ratou iti iho i te 10 mekameka polypeptide. Ko te kupu synthesizes RNA polymerase 1 (transcribes) ira e e muri iritihia ki te ngā pūmua. whai wāhi te tuarua hiki ira, e e muri iritihia ki pūmua. RNA polymerase 3 whakaatu ngā eu iti whākōkī taimaha rāpoi e te hunga tika tairongo ki ārepa amatinu. Otiia kihai i matou faaoti i runga i te mea rite he RNA polymerase! Na ka karangatia e whākōkī e rave i roto i te kōtuitui o ngā rāpoi ngota waikawa ribonucleic. I roto i te tikanga kuiti mohio ki e tenei polymerase RNA DNA-ti'aturi, e mahi i runga i te pūtake o te kopu o te waikawa deoxyribonucleic. E mea faufaa no te he mahi roa, me te angitu o ngā kaiao ora whākōkī. Ka taea te kitea RNA polymerase i roto i ngā pūtau katoa, me te maha huaketo.
Ko te wehenga i runga i te pau
Tei runga i te hanganga subunit o polymerases RNA e wehea ki e rua ngā rōpū:
- Ko te tuatahi mo ki hiki he maha iti o ira i roto i te genomes o ohie. Hoki te mahi i roto i tenei take e kore e rapua e pānga ture matatini. Na reira, i konei e pā ana ki whākōkī katoa e ngā o tetahi anake subunit. Ka rite ki te tauira e taea häpaingia te polymerase RNA bacteriophage me pungaraungao.
- Tenei rōpū ngā katoa polymerase RNA eukaryotic me te huakita, e te hunga uaua whakaritea. Ko ratou manganga complexes mnogosubedinichnye pūmua e taea te tuhi mano o ira rerekē. I roto i te mahi, te whakautu i enei ira ki te maha nui o tohu ture e kua riro i ngā āhuatanga pūmua me nucleotides.
Ko pai here me te whakangāwaritanga o te āhuatanga tūturu wehenga hanganga, me te mahi pērā.
He aha e te RNA polymerase ahau?
i whakaritea ratou mahi o te mātauranga o tuhinga tuatahi o ira rRNA, e ko, he ratou te nui tino. Ko te whakamutunga e mohiotia atu i raro i te ti'araa o 45S-RNA. Ratou roa Ko e pā ana ki 13 000 nucleotides. Mai i reira e hanga e 28S-RNA, 18S-5.8S te RNA-RNA. Nā ki te meka e kua hanga ratou tetahi anake transkriptor, e tango te tinana he "taurangi" e ka te rāpoi ngota, kia whai ahua i roto i rite moni. I te wa ano te hanga o RNA tika haere 7000 anake nucleotides. Ko te toenga o te tuhinga iti kei roto i te karihi. I runga i te taua toenga nui whakapono te e te mea e tika mo te tīmatanga o te hanganga o ribosomes. Ko te maha o enei polymerases i ngā pūtau o te taata teitei kare a tawhio noa te tohu o 40 mano wae.
Pehea te whakaritea reira?
Ko te kupu, Kei a tatou te polymerase RNA tuatahi (rāpoi prokaryotes-hanganga) te whakaaro pai. I roto i tenei take, te subunit nui, rite, te mea, me he tokomaha nui o te tahi atu polypeptides taimaha rāpoi tiketike, i reira e āta wehea ngā rohe mahi, me te hanganga. I roto i pūruatanga o ira me ki te whakatau i to ratou hanganga tuatahi kua tāutuhia e te pūtaiao evolutionarily oranga wahi o mekameka. Mā te whakamahi i te kīanga pai, i whakahaere hoki te kairangahau tātari mutational e taea ki tatou kōrero e pā ana ki te hiranga mahi o rohe takitahi. Hoki tenei whakaaro, te whakamahi i mutagenesis pae-whakahaua ki te huri i te mekameka polypeptide takitahi, me taua amino whakarerekētia subunits waikawa whakamahia i roto i te whakaminenga o whākōkī ki te tātari muri o ngā āhuatanga, i whiwhi nei i roto i te hanganga raraunga. I tuhia te reira e tika ana ki tona whakahaere o te polymerase RNA tuatahi i roto i te aroaro o te Arepa-amatina kore e (he taonga tino paitini, whiwhi nei i te toadstool ha ma) tauhohe.
te mahi
Rua te tuatahi, me te tuarua o nga polymerase RNA kia tīariari i roto i ngā puka e rua. Ko tētahi o ratou e taea e mahi ki te kōkiri i te patohanga motuhake. Ko te tuarua - te RNA polymerase DNA-ti'aturi. whakakitea ana tēnei huru i roto i te mahi nui rawa o te mahi. Kaupapa ako atu, engari inaianei e matau ana tatou e tei te reira i runga i rua ngā āhuatanga tuhi, e kua kīia ki rite SL1 me UBF. Tautautefito te whakamutunga - e taea te whakawhiti tika ki te kaiwhakatairanga, i titau te SL1 UBF aroaro. Kua Ahakoa experimentally kua whakapumautia reira e taea te DNA-ti'aturi RNA polymerase whai wāhi i roto i te patohanga i te iti me te kahore te aroaro o te muri. Ko mo te mahi noa o tenei tikanga e hiahiatia tonu UBF. Aha na? Tino pera tawhiti rahua ki te whakatū i te take o tenei whanonga. Ko tētahi o te whakamārama tino rongonui kōrero e kaiwhakamana UBF he ahua o stimulant tuhi rDNA ina tupu ia me te whakawhanake. A, no te takoto wāhanga puta, ka tonu te taumata iti rawa e hiahiatia o mahi. e kore te mea tino hoki ia te wahi o āhuatanga tuhi. Here kia mahi RNA polymerase. Ko te mahi o tenei whākōkī taea tautoko te purei o iti "poraka hanga" o te tinana, e tika ana ki nei tonu whakahou reira mo tekau tau.
Ko te rōpū tuarua o whākōkī
whakaritea ratou mahi e te whakaminenga o multiprotein kaiwhakatairanga preinitsiatornogo matatini o te piha haapiiraa tuarua. Nuinga o ngā wā faaite tenei te i roto i te mahi o nga pūmua motuhake - activators. Ka rite ki te tauira ko te TBP. Kei te whai pānga te reira i āhuatanga e he wahi o TFIID. Ratou - he ūnga mō te p53, NF Kappa B, me pera i runga i. Ko tōna mana i roto i te tukanga o te ture, me te whakarato i pūmua huaina coactivators. Tauira ko te Gcn5. He aha e hiahia ana tatou enei pūmua? mahi ratou rite whāurutau e whakarite te ngā o activators me āhuatanga e te hunga i roto i te matatini preinitsiatorny. Hei whakatika i puta te tuhi, me whai koe i te āhuatanga initiator tika. Ahakoa te meka e ono o ratou, hāngai taunekeneke ki te kaiwhakatairanga pea te kotahi anake. Hoki ētahi atu take titau matatini preformed o te polymerase RNA tuarua. Ano, i roto i enei tukanga he āhuatanga proximal pātata - 50-200 anake takirua i te pae te wahi tīmata te tuhi te. Kei roto ratou i te tohu o te here o te pūmua activator.
āhuatanga motuhake
E te hanganga subunit o nga whākōkī o te take mai rerekē i runga i to ratou tūranga mahi i roto i te patohanga? Ko te whakahoki tangohia ki tenei pātai he kahore, engari whakapono e ko te reira pea pai. Pehea i pānga reira RNA polymerase? mahi pūmua whākōkī hanganga ohie - te iti whānuitanga o te tuhi o ngā ira (ara he wahi iti ranei). Tauira ko te kōtuitui o RNA primers Okazaki whatiwhatinga. Ko te pū kaiwhakatairanga o te polymerases RNA o huakita me phages ko e whākōkī he kau ma'u o hanganga ohie, me te he rere. Ka taea te kite i tenei i roto i te tukanga o te tukuruatanga DNA i roto i te huakita. Ahakoa e taea e tatou e whakaaro tenei: hanganga matatini ka ako genome T noa Petapaki, i roto i te whanaketanga, i tuhia ai e faahiti whakawhiti i waenganui i ngā rōpū ira te tuhi, i kitea ai e te matatini whakamahia hoki tenei ope RNA polymerase. Ko, e kore te he paru ohie i roto i ngā take pēnei i piri. titau tenei he maha o mau hopearaa:
- Me e taea ki te ite i ngā kaiwhakatairanga rerekē RNA polymerase o eukaryotes me huakita.
- E mea titauhia e te whākōkī he whakautu motuhake ki rerekē pūmua-tauwehe.
- Me hoki kia taea ki te huri i te āhukahuka o te pū o te nucleotide raupapa tātauira DNA RNA polymerase. Ki te mahi i tenei, te whakamahi i te momo o effectors pūmua.
whai te reira i hiahia o te tinana mo te atu "hanga" huānga. tauturu i pūmua ki te tuhi i te matatini o te RNA polymerase ki tino kawe i ona mahi. E pā ana tēnei, mo te nuinga, te whākōkī hanganga matatini, i roto i nei te taea o te whakatinana i te hōtaka whānui o te mōhiohio ā-ira. Nā ki ngā raruraru, ka taea e tatou mau te ahua o te hanganga nahanaha o RNA polymerase.
Nahea te tukanga o te te tuhi?
He reira kawenga mō te takawaenga ki te polymerase RNA he ira? Hei tīmata o te tuhi: te tukanga i roto i eukaryotes e wahi i roto i te karihi. I roto i ngā prokaryotes, rere reira i roto i te moroiti. Ko te hononga i waenganui i te polymerase ko te parau tumu hanganga taketake o te rāpoi tautoko kahui takitahi. I runga i nga take o te pāhekoheko e taea mea e he noa DNA he tauira me te e kore e huri i roto i te tuhi. Mai DNA ko te paru katoa, ko te mea etahi, e te ira ngā he kawenga hoki tenei waerau e taea e, engari ka waiho hei tino roa te wa. kia kore tatou e wareware e kei te DNA 3.1 piriona toenga nucleotide. Na reira, atu e tika ana ki te mea e tutuki mo ia momo o RNA tona DNA. Hoki te rere o te tauhohenga polymerase hiahia pūngao me te ribonukle-ozidtrifosfato substrates. Ki te kei tetahi hanga e 3 ', 5'-phosphodiester here i waenganui i ribonukleozidmonofosfatami. tīmata kōtuitanga RNA rāpoi ngota i roto i etahi raupapa DNA (kaiwhakatairanga). Aukatihia ai te tukanga i ngā pae whakamutunga (whakamutunga). ka karanga te pae, whai wāhi nei te konei te transcriptional. I roto i te eukaryotes, i reira he te tikanga kotahi anake ira, ia taea prokaryotes hoki riro mongamonga maha o waehere. Ia transcriptional he wāhi uninformative. E tū ana raupapa nucleotide tauwhāiti e taunekeneke ki ngā āhuatanga ture transcriptional whakahuatia i runga ake.
polymerase RNA kitakita
Enei microorganisms kotahi whākōkī he kawenga mo te kōtuitui o mRNA, rRNA ko tRNA. kua he pakeke 5 subunits te rāpoi ngota polymerase toharite. E rua o enei mahi rite honohono mema o whākōkī. Ko tētahi atu subunit whai wāhi i roto i te tomokanga o te ariā. He he ano hoki te wāhanga o te paru nonspecific mō te kōrero ki te DNA. Na kua te subunit whakamutunga kua mau mai i te polymerase RNA i roto i te puka mahi. Kei te tuhia te reira e kore e nga rāpoi paru i roto i te "noa" whakatere i te cytoplasm o huakita. A, no te e whakamahia polymerases RNA, ka herea ratou rohe DNA kore-motuhake, me te e tatari noa whakatuwheratia te kaiwhakatairanga hohe te. He bit raruraru i te kaupapa, kia mea ai e huakita ko te tino watea ki te ako pūmua me ratou mana ki runga ki te polymerase waikawa ribonucleic. Rawa watea hoki ki a ratou whakamātau i whakaongaonga inhibition o te āhuatanga takitahi ranei. Nā ki taea ratou auau reproduction teitei kia āhua hohoro te tiki i te hua e hiahiatia ana. Aue, e kore e taea te whakahaere te ako tangata i te taua whakawhetai tere tere ki to tatou kanorau hanganga.
RNA polymerase "mau" i roto i ngā puka?
E haere mai ki te mutunga arorau te tuhinga. utua te aro matua i ki te eukaryotes. Ko reira he tonu archaea me huaketo. Na e hiahia ana koe ki te utu i te moka o te whakarongo me enei momo o te ora. Ko te mahi faufaa o Archean reira he kotahi anake rōpū o polymerases RNA. Ko te mea tino rite i roto i ona āhuatanga ki te rōpū eukaryotes toru. Kua maha pūtaiao kua fokotu'u aha e taea e matou te titiro i te arche mau te tipuna whanaketanga o polymerases motuhake. Ko reira ano hoki ngā, me te hanganga o wheori. Ka rite ki mua i tuhituhia, e kore katoa o enei rauropi i to ratou ake polymerase. A kei hea he reira, ko reira he subunit kotahi. Kei te whakapono te reira e te whākōkī viral i takea mai i polymerases DNA, hei utu o ngā hanganga RNA matatini. Ahakoa e tika ana ki te kanorau o tenei rōpū o microorganisms tutuki whakatinanatanga rerekē te tikanga koiora hoatu.
mutunga
Aue, e kore e tangata ano i vsoy mōhiohio e tika ana e hiahiatia ana mo te māramatanga o te huinga ira. A, e anake i taea e ia i mahia! Tata e waiwai mate katoa tika te pūtake ira - pā rawa tenei ki nga wheori e tonu homai tatou raruraru ki mate, me te pera i runga i. Ko te mate tino matatini me te mahu - he hoki ratou, i roto i te meka, hangatonu pe ta'efakahangatonu whakawhirinaki i runga i te genome tangata. A, no te ako tatou ki te mahino roto ratou, a ka tono tenei matauranga ki te painga o te tau nui o ngā raruraru, me mate ka mutu noa ki te tīariari. Na he mea o te mua, he maha nga mate i mua nanakia pērā i koroputaputa, whiu. Whiwhi rite ki te haere repe, mare. Otiia e kore e akaanga, no te mea e fehangahangai tatou ki te maha noa nui o mau tamataraa rerekē e hiahia ana koe ki te kitea te whakahoki. A ka kitea taua mea, no te mea te haere i reira ki te rave i te reira.