Qhov Tseem Ceeb Qhov txawv - Inducible vs Repressible Operon
Ib qho operon yog ib chav ua haujlwm ntawm genomic DNA uas muaj pawg ntawm cov noob nyob rau hauv kev tswj hwm ntawm ib tus neeg txhawb nqa. Cov kev cai ntawm noob yog ua tiav los ntawm kev tswj ntawm ib qho operon los ntawm induction lossis kev tsuj. Operons muaj ob hom: inducible operons thiab repressible operons. Inducible operon yog ib hom operon uas tau hloov los ntawm cov tshuaj substrate, piv txwv li, inducer. Nyob rau hauv ib tug repressible operon, cov kev cai yog ua los ntawm ib tug chemical tshuaj hu ua co-repressor uas ib txwm yog qhov kawg khoom ntawm txoj kev metabolic. Qhov no yog qhov sib txawv tseem ceeb ntawm inducible thiab repressible operons.
Tus neeg ua haujlwm yog dab tsi?
Operon yog ib pawg ntawm cov txheej txheem genes uas tau qhia lossis tswj los ntawm ib tus neeg txhawb nqa thiab suav tias yog lub luag haujlwm ntawm genomic DNA. Muaj peb yam hauv ib qho operon. Lawv yog cov txhawb nqa, tus neeg teb xov tooj, thiab cov noob. Cov kab lis kev cai ntawm cov noob tau hloov mus rau hauv mRNA ib ntus los ntawm cov txheej txheem hu ua transcription. Ib qho operon tsim ib chav tsev ntawm mRNA ib ntus, uas tom qab ntawd tau muab txhais ua cov protein sib cais, feem ntau cov enzymes koom nrog hauv txoj hauv kev metabolic. Thaum pib, operons tau pom nyob rau hauv prokaryotes, tab sis tom qab ntawd lawv tau pom nyob rau hauv eukaryotes ib yam nkaus. Prokaryotic thiab eukaryotic operons ua rau lub genesis ntawm polycistronic mRNAs thiab monocistronic mRNAs, feem. Operons kuj tuaj yeem pom ntawm cov kab mob bacteriophages (cov kab mob kis kab mob).
Dab tsi yog Cov Neeg Ua Haujlwm Tsis Txaus Siab?
Ib qho operon inducible yog ib lub noob caj noob ces encodes ib qho sib npaug ntawm cov enzymes txuam nrog txoj hauv kev catabolic. Nws yog inducible thaum metabolite / substrate nyob rau hauv txoj kev no activates transcription ntawm cov noob uas encode cov enzymes tshwj xeeb. Qhov kev ua kom no tuaj yeem tshwm sim los ntawm tus neeg tawm tsam thaum nws tsis ua haujlwm lossis koom tes. Lub inducible operon yog switched los ntawm ib tug inducer. Ib qho inducible operon muaj cov khoom xws li cov txheej txheem genes, tus neeg teb xov tooj gene, txhawb nqa gene, regulator gene, repressor, thiab inducer. Inducible operons muaj ib los yog ntau yam genes. Lub lac operon yog qhov piv txwv zoo tshaj plaws rau inducible operon.
Daim duab 01: Inducible operon – Lac Operon
Nws muaj peb hom kab ke; Z, Y thiab A uas sau ib qho mRNA thiab txhais cov mRNA rau peb enzymes galactosidase, lactose permease thiab transacetylase, feem. Tus neeg teb xov tooj gene nyob ib sab ntawm cov txheej txheem genes thaum tswj kev ua haujlwm ntawm lawv.
Cov Neeg Ua Haujlwm Txhaum Cai yog dab tsi?
Lub repressible operon yog tswj nyob rau hauv lub xub ntiag ntawm ib tug tshuaj hu ua co-repressor. Ib tug co-repressor yeej ib txwm yog ib tug kawg khoom ntawm ib tug metabolic txoj kev. Nyob rau hauv lub xub ntiag ntawm ib tug co-repressor, lub operon yog hais tias yuav tsum tau hloov. Tryptophan operon (trp operon) yog ib qho piv txwv rau repressible operon. Cov txheej txheem genes, regulator gene, tus neeg teb xov tooj gene, txhawb nqa gene, thiab co-repressor muaj nyob rau hauv trp operon. Lub trp operon muaj tsib cov qauv ntawm cov noob uas sau cov mRNAs uas tom qab ntawd tau muab txhais thiab coded rau cov proteins uas ua haujlwm li enzymes.
Daim duab 02: Tus neeg ntxeev siab Operon – Tryptophan Operon
Cov noob caj ces yog tswj hwm los ntawm cov neeg ua haujlwm tshwj xeeb cov noob tam sim no ua ib feem ntawm trp operon. Lub co repressor yog tsim los ua ib qho khoom kawg los ntawm txoj kev metabolic uas tshwm sim hauv lub cell los yog nkag mus rau hauv lub cell los ntawm sab nraud. Qhov concentration ntawm co-repressor yog ncaj qha proportional rau cov kev cai ntawm transcription nyob rau hauv lub cell. Nrog rau qhov nce ntawm cov co-repressor concentration, apo-repressor thiab co-repressor complex yog tsim. Lub apo repressor yog ib qho protein thiab yog coded los ntawm cov regulator noob tam sim no nyob rau hauv lub operon. Qhov kev sib txuam no khi rau thaj tsam tus neeg teb xov tooj thiab nres qhov kev hloov pauv ntawm cov txheej txheem genes. Thaum lub sij hawm qis ntawm co-repressor concentrations, kev koom tes ntawm apo-repressor thiab tus neeg teb xov tooj gene yog tiv thaiv. Qhov no ua rau kev txuas ntxiv ntawm kev tsim cov co-repressor. Lub apo-repressor thiab co-repressor complex ua ke nrog tus neeg teb xov tooj gene thiab tua cov noob qhia. Qhov no tiv thaiv cov txheej txheem ntawm kev sau thiab yog li nres cov synthesis ntawm enzymes.
Dab tsi yog qhov zoo sib xws ntawm Inducible thiab Repressible Operon?
- Inducible thiab repressible operons muaj cov txheej txheem genes nrog cov haujlwm zoo sib xws thiab raug tswj los ntawm ib tus neeg txhawb nqa.
- Ob hom kev ua haujlwm muaj xws li kev tswj hwm tsis zoo uas yog tswj los ntawm tus neeg tawm tsam.
- Tus neeg tawm tsam yog coded los ntawm cov noob tswj hwm tam sim no nyob rau hauv ob tus neeg ua haujlwm, thiab thaum tus neeg tawm tsam txuas nrog tus neeg teb xov tooj, nws tiv thaiv kev sau.
Qhov txawv ntawm Inducible thiab Repressible Operon yog dab tsi?
Inducible vs Repressible Operon |
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| Nyob rau hauv inducible operons, cov noob raug kaw kom txog thaum ib qho metabolite inactivates lub repressor. | Nyob rau hauv repressible operons, noob tau hloov mus txog rau thaum lub repressor yog qhib los ntawm ib tug tshwj xeeb metabolite. |
| Cov neeg ua haujlwm tsis txaus ntseeg ua haujlwm hauv catabolic txoj hauv kev. | Cov neeg ua haujlwm tsis txaus ntseeg ua haujlwm hauv txoj hauv kev anabolic. |
| Enzyme Synthesis | |
| Cov khoom noj siv hauv txoj hauv kev qhib enzyme synthesis. | Kev tsim khoom raug hloov tawm los ntawm cov khoom kawg ntawm txoj hauv kev uas ua rau cov enzyme synthesis. |
| Examples | |
| Lac operon is an inducible operon. | Trp operon yog ib qho kev tsim txom. |
Summary – Inducible vs Repressible Operon
Ib qho operon yog pawg ntawm cov noob uas tswj los ntawm ib tus neeg txhawb nqa. Lawv yog ob hom operons raws li cov haujlwm uas lawv ua. Lawv yog cov neeg ua haujlwm tsis muaj zog thiab ua rau muaj kev kub ntxhov. Inducible operon yog tswj los ntawm lub substrate tam sim no nyob rau hauv txoj kev metabolic thaum repressible operon yog tswj los ntawm lub xub ntiag ntawm ib tug metabolic kawg khoom hu ua co-repressor. Qhov no yog qhov sib txawv tseem ceeb ntawm inducible thiab repressor operon.
Download PDF Version of Inducible vs Repressible Operon
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline hom phiaj raws li daim ntawv ceeb toom. Thov download PDF version ntawm no Qhov txawv Ntawm Inducible thiab Repressible Operon.
