Tukatuka - Ko ... tukatuka tuipūmua (pou-transcriptional tuipūmua whakarereke)

E wehewehe ana tenei wā te whakatinanatanga o ngā mōhiohio ā-ira i roto i ngā pūtau pērā i eukaryotes me prokaryotes.

Tikanga o tenei ariā

I roto i te reo Ingarihi, te tikanga te wā "maimoatanga, hangarua." Tukatuka - Ko te hanganga o ngā rāpoi ngota RNA pakeke i mua te RNA-. I roto i te mau parau te tahi atu, tenei huinga o tauhohe e arahi ki te huringa o te hua tuhinga tuatahi (te mua-RNAs o ngā momo rerekē) i roto i te rāpoi ngota kē-mahi.

Ki te whakaaro ki te tukatuka o p- me tRNA, te reira maha mai ki raro ki tau hatepenga atu i nga pito o te rāpoi ngota o te anō whatiwhatinga. Ki te kōrero tatou e pā ana ki te mRNA, kia tuhia te reira i konei e i roto i eukaryotes, e wahi te tukanga i roto i te maha o ngā wāhanga.

Na, i muri i ta tatou i haapii e te tukatuka - ko te huringa o te tuhinga tuatahi ki te rāpoi ngota RNA pakeke, kia puta ki te whakaaro o ona āhuatanga.

Ko te āhuatanga matua o te ariā

taea ngā tenei te whai ake:

• te whakarerekētanga pito e rua o te rāpoi ngota, me te RNA, i roto i te akoranga o e kua piri ratou e raupapa nucleotide motuhake e whakaatu wahi timata (mutunga) o te haapurororaa;
• splicing - Topenga uninformative raupapa waikawa ribonucleic e hāngai ana ki introns DNA.

Ka rite ki hoki prokaryotes, e kore e ngohengohe ki te tukatuka mRNA ratou. He te kaha ki te mahi i te mutunga o te kōtuitui.

Hea puta te tukanga i roto i te pātai?

Tetahi tukatuka rauropi RNA e wahi i roto i te karihi. Kei te kawea te reira i roto i na whākōkī motuhake (ratou rōpū) mo ia rāpoi ngota momo takitahi. hoki tukatuka kia kitea ki ngā hua translation pērā i te polypeptides e e tika tai'o i te mRNA. E ngohengohe ana ki nga rāpoi kawainga pera-ka karanga o te nuinga o pūmua enei huringa - collagen, paturopi, whākōkī kūnatu, etahi hormones, a ka tīmata te mahi tūturu o te tinana.

Kua kē matou ako e te tukatuka - ko te hanganga o te RNA pakeke i mua te RNA-. Na ko reira e tika ana ki te ruku hōhonu ki te āhua o te nuinga o te waikawa ribonucleic.

RNA: te āhua matū

Ko te waikawa ribonucleic, i te mea he copolymer o pyrimidine me purine ribonukleitidov e e hono ki tetahi ki tetahi, kia rite ki i roto i te DNA 3 'tenei - piriti 5'-phosphodiester.

Ahakoa te meka e he rite enei momo e rua o ngā rāpoi ngota, rerekē ratou i runga i te maha o te papa whenua.

Ko te āhuatanga o te RNA me te DNA

Tuatahi, he reira i roto i te toenga waro ki nei piri ana pyrimidine me purine turanga, te rōpū Phosphate waikawa ribonucleic - ribose, i DNA te taua - 2'-deoxyribose.

Tuarua, ko te wāhanga rerekē, me te pyrimidine. wāhanga e rite ko nga nucleotides adenine, cytosine, guanine. I roto i te RNA, he hakari hei utu o thymine uracil.

A toru, He te RNA 1 he hanganga mekameka, me DNA - muingota 2-herea. Ko whenu waikawa ribonucleic wahi hakari o te wehenga tawhiti ritenga (raupapa tautoko) i te mea reira, e nehenehe o te mekameka kotahi, me te katinga ki te hanga i "napikeni" - hanganga, e hua ana ki te āhuatanga o te tōrino-2 (rite whakaaturia i runga ake).

A maha, no te mea te RNA - he mekameka kotahi, i te mea tautoko ki te whenu DNA tuatahi, guanine kore hiahia e reira reira i roto i te te ihirangi taua rite te cytosine me adenine - uracil rite.

A pae, kia kia hydrolyzed te RNA ki alkali ki te 2 ', 3'-diesters o mononucleotides huringa. Ko te tūranga o te paparetanga takawaenga nui 2 ', 3', 5-triester, taea ki te hanga i roto i te tukanga rite ki te DNA e tika ana ki te ngaro ona rōpū 2'-hydroxyl. Na roto i te rite ki te DNA kawakore lability o te waikawa ribonucleic ko te taonga whai hua mō ngā take tātaritanga, me mo te tātari.

Ko te kōrero i roto i roto i te RNA 1-paea te tikanga whakatinana rite te raupapa o purine me pyrimidine turanga, e ko, he hanganga mekameka polymer tuatahi.

Tenei raupapa, ko te ira tautoko mekameka (whakawaehere), me i te RNA "readout." Nā ki tenei taonga o te rāpoi ngota waikawa ribonucleic āta taea herea ki te mekameka waehere, engari ko te kore e taea ki te mahi i tenei ki kore-Tapa whenu DNA. raupapa RNA, ki te kahore hoki whakakapi T U, rite ki taua e pā ana ki te ira mekameka kore Tapa-.

momo o te RNA

Tata ki te katoa o ratou e whai wāhi i roto i te tukanga, pērā i te pūmua biosynthesis. momo mohiotia o te RNA:

1. Matrix (mRNA). Tenei cytoplasmic rāpoi waikawa ribonucleic e mahi rite tāhū, te kōtuitanga pūmua.
2. Ribosomal (rRNA). Tenei rāpoi ngota RNA cytoplasmic, te taviniraa rite wāhanga hanganga pērā i ribosomes (organelles whai wāhi i roto i te kōtuitanga pūmua).
3. Transportation (tRNA). Tenei rāpoi waka o waikawa ribonucleic e whai wāhi i roto i te mōhiohio translation (translation) mRNA ki te raupapa o waikawa amino i kē pūmua.

He wāhanga nui o te RNA o nga tuhinga tuatahi e kua whakaputaina i roto i ngā pūtau eukaryotic, tae atu ki ngā pūtau kararehe, whai wāhi i roto i te tukanga tuukinotanga karihi, ka whai te kōrero i roto i te cytoplasm tūranga hanganga ranei.

I roto i ngā pūtau tangata (peu) i kitea e kore e whai wāhi hāngai te piha haapiiraa o waikawa ribonucleic karihi iti i roto i te kōtuitanga pūmua, engari e pa ana tukatuka RNA, me te katoa pūtau "hoahoanga." Ratou rahi rerekē, i roto ratou 90 - 300 nucleotides.

waikawa Ribonucleic - te rauemi taketake ira i te maha o huaketo o ngā tipu me ngā kararehe. Ētahi wheori kei roto RNA, e kore haere taua taahiraa rite te patohanga whakamuri o te RNA ki DNA. Otiia mo maha huaketo kararehe, mo retroviruses tauira, āhuatanga e te translation whakamuri o te huinga ira RNA whakahaua tuhi whakamuri (polymerase DNA) RNA-ti'aturi ki te hanga i kape DNA 2-helical. I roto i te nuinga o te wā putanga tuhinga DNA 2-helical i whakaurua ki te genome whakarato atu faaiteraa o ira viral me te wa whakahaere o te hou genomes kape RNA (me viral).

whakarerekētanga pou-transcriptional o RNA

E synthesized Ko tōna ngā rāpoi ngota ki te polymerases RNA, tonu ki precursors functionally hohekore ngāue, ara te mua-RNA. ae whakaputaia ketia ana ratou ki te rāpoi ngota kua pakeke anake i muri haere i te whakarerekētanga e hāngai ana pou-transcriptional o te RNA - nga wāhanga o tona matuatanga.

i te pānui i te hanganga o matu'otu'a mRNA i roto i te ariā me te RNA polymerase II i roto i te taahiraa elongation. Na roto i te 5'end o te āta tipu whenu RNA 5'end piri GTP, ka piri orthophosphate. I tua atu, me te haerenga mai o mewaro guanine 7-methyl-GTP. Tenei rōpū ngā, i te mea i roto i te wahi o te mRNA, i huaina "tepe" (pōtae pōtae ranei).

Tei runga i te tuipūmua momo (ribosomal me waka, kopu, me ētahi atu) e i raro precursors ki ngā akatuke'anga whai. Hei tauira, kei te kanawa nga precursors mRNA, methylation, paerangi, polyadenylation, a ētahi wā whakatika.

Eukaryotes: he tirohanga whānui

mahi pūtau eukaryotic rite te rohe o kaiao ora, a ka kei reira te pata. I tua atu ki te huakita, archaea, he karihi rauropi katoa. Plants, harore, kararehe, tae atu ki te rōpū o kaiao, ka karanga protists - katoa te mahi kaiao eukaryotic. Ko ratou e rua 1-pūtau me te multicellular, engari katoa o te mahere whānui o te hanganga pūtau. Kei te whakapono te reira e ko enei rauropi kia kanorau i te takenga mai taua, kia rite ki te putanga, he rōpū o karihi mohio a rite te taxon monophyletic o te ana'iraa rawa.

I runga i te whakapae rongonui, puta eukaryotes 1.5 - 2 piriona tau ki muri .. homai tūranga nui i roto i to ratou kunenga te symbiogenesis - symbiosis pūtau eukaryotic, i i te matua e taea o phagocytosis, me kitakita, horomia ia - tupuna o plastids me pungaraungao.

Prokaryotes: āhuatanga whānui

Tenei rauropi 1-pūtau e whai kahore karihi (rēhita), te toenga o nga organelles membrane (ä-). Ko te rāpoi ngota anake annular 2-mekameka DNA nui kei te wahi nui o te rauemi ira o te pūtau ko tetahi e kore nei e hanga i te matatini ki te pūmua histone.

Hoki prokaryotes ngā archaea me te huakita, tae atu cyanobacteria. Uri enucleated pūtau - organelles eukaryotic - plastids, pungaraungao. E wehea ratou ki 2 taxa i roto i te ana'iraa rohe: Archaea me Bacteria.

e kore e ēnei pūtau i te kōpaki karihi, e te tākai DNA wahi i waho te whai wāhi o histones. Osmotrofny ratou momo kai, me te kei te rauemi ira o tetahi rāpoi ngota pītauira katia nei i roto i te whakakai, me i reira ko tetahi anake replicon. I roto i ngā prokaryotes he organelles e he hanganga membrane.

Rerekē eukaryotes i prokaryotes

Ko te āhuatanga taketake o ngā pūtau eukaryotic he e pā ana ki te kitenga i roto i a ratou i te taputapu ira, kei nei i roto i te karihi, te wahi e tiakina ai e te anga. Ratou DNA rārangi e pā ana ki pūmua histones, te tahi atu pūmua o pūira, i he mea motu ke i roto i te huakita. Tikanga, i roto i to ratou huringa ora tapaea karihi 2 wāhanga. He Kotahi te huinga haploid o ngā pūira, a muri hanumi, 2 pūtau haploid te hanga i te diploid, e kua Kei roto te huinga tuarua o pūira. Reira tupu hoki e te wa i muri mai ka tuwhaina e ano he pūtau riro haploid. Tenei ahua o huringa ora, me te diploidy i whānui, e kore e āhuatanga mō ngā prokaryotes.

Ko te rerekētanga tino ngā ko te aroaro o organelles motuhake i roto i eukaryotes, e whai ratou ake taputapu ira, me te tini i te wehenga. E karapotia e te membrane ēnei hanganga. Enei organelles Ko nga pungaraungao me plastids. E ai ki te hanganga o te ora, me te he Koinei rite ki te hunga o te huakita ratou. ue'i tenei tūkunga kaipūtaiao ki te whakaaro e pā ana ki te meka e ratou - te uri o kaiao kitakita e kua tomo ki symbiosis ki eukaryotes.

I roto i ngā prokaryotes, i reira te mea he maha iti o organelles, tetahi o i karapotia e te membrane tuarua. hapa ratou i te pūnaha kiriuwhi, te taputapu Golgi, te lysosomes.

Ko tētahi atu rerekētanga nui 1 i eukaryotes prokaryotes - aroaro endocytosis tītohunga i roto i eukaryotes, tae atu phagocytosis i roto i te nuinga o ngā rōpū. Ko te whakamutunga, ko te kaha ki te hopu i te tomo i te membrane mirumiru, ka ngaungau i te ngā matūriki mārō. whakarato ana tēnei tukanga nui mahi tiaki i roto i te tinana. Ko te takanga o te phagocytosis, hai e tika ana ki te meka e ratou pūtau i te rahi toharite. kaiao Prokaryotic ko te mahinga iti, rite te putanga, i roto i te whanaketanga o eukaryotes, i reira ko tetahi whakaritenga e pā ana ki te supply o te pūtau he nui nui o te kai. Ka rite ki te hua, ka puta te konihi turanga tuatahi i roto ia ratou.

Tukatuka rite tetahi o nga wāhanga o te pūmua biosynthesis

Tenei wāhanga tuarua, e haamata i muri i te tuhi. Tukatuka o pūmua puta anake i roto i eukaryotes. Tenei matuatanga o te mRNA. Hei kia pau, ko reira te tango o te whenua e kore e e waehere mo te pūmua, me te mana hono.

mutunga

I roto i tenei tuhinga e whakaahuatia reira e tohu tukatuka (koiora). ka mea ano e tenei RNA ngā ona momo me te whakarereke pou-transcriptional. Whakaaro nga āhuatanga motuhake o eukaryotes me prokaryotes.

I te pae hopea ko reira utu ki te fakamanatu e te tukatuka - ko te hanganga o te RNA pakeke i mua te RNA-.