Qhov sib txawv tseem ceeb ntawm pab pawg I thiab pab pawg II introns yog tias hauv pawg I introns, cov tshuaj tiv thaiv kab mob yog pib los ntawm guanosine cofactor, thaum nyob rau hauv pab pawg II introns, cov tshuaj tiv thaiv kab mob yog pib los ntawm adenosine.
Pre-mRNA yog cov ntawv sau tseem ceeb uas muaj ob qho tib si introns thiab exons. Pre-mRNA yuav tsum hloov mus rau mRNA ua ntej kev txhais lus. RNA splicing lossis pre-mRNA splicing yog ib qho kev hloov pauv tom qab hloov pauv. Hauv RNA splicing, introns raug tshem tawm los ntawm pre-mRNA molecule, thiab exons tau koom ua ke. Pawg I thiab Pawg II introns yog tus kheej-splitting intros. Lawv splice tawm ntawm pre-mRNA molecule yam tsis muaj kev pab los ntawm lwm yam enzyme. Yog li ntawd, lawv yog RNA enzymes los yog ribozymes uas catalyze lawv tus kheej splicing los ntawm pre-mRNA. Ntxiv mus, lawv muaj peev xwm ua haujlwm raws li cov khoom txawb. Thaum lub sij hawm splicing, ib tug series ntawm trans-esterification tshwm sim nyob rau hauv thiaj li yuav excise lub intron thiab ligate lub exons. Cov ribozymes no muaj nyob rau hauv tag nrho peb lub npe, suav nrog cov kab mob, archaea thiab eukaryotes.
Pab kuv Introns yog dab tsi?
Pab pawg I introns yog ib hom kev sib txuas ntawm tus kheej ribozymes pom nyob rau hauv cov kab mob, bacteriophages thiab eukaryotes (organellar thiab nuclear genomes). Lawv muaj nyob rau hauv cov noob tseem ceeb. Lawv muaj peev xwm catalyze lawv tus kheej splicing los ntawm pre-mRNA molecule. Pawg I intros tej zaum yuav muaj ob peb puas mus rau peb txhiab nucleotides. Tsis tas li ntawd, lawv muaj qhov sib npaug me me ntawm cov kab mob.
Daim duab 01: Pawg I Introns
Cov qauv thib ob tau txais kev txuag hauv plaub thaj tsam luv. Muaj ob qhov kev hloov pauv hloov pauv cov kauj ruam ntawm kev sib txuas. Pawg I introns pib splicing mechanism los ntawm nucleophilic nres ntawm 3 'hydroxyl ntawm ib tug Guanosine cofactor ntawm 5P splice site.
Dab tsi yog Pawg II Introns?
Pab Pawg II introns yog ib hom kev sib txuas ntawm tus kheej introns pom nyob rau hauv cov kab mob uas muaj nyob hauv peb lub npe. Lawv yog ribozymes uas catalyze lawv tus kheej splicing cov tshuaj tiv thaiv los ntawm pre-mRNA. Lawv muaj nyob rau hauv rRNA, tRNA thiab protein-coding noob. Tab sis lawv tsis pom nyob rau hauv cov genomes nuclear, tsis zoo li pab pawg kuv introns.
Daim duab 02: Pawg II Introns
Pab pawg II introns catalyze splicing ntawm ob theem transesterification zoo ib yam li pab pawg I introns. Cov enzymes pib cov tshuaj tiv thaiv splicing los ntawm nucleophilic nres ntawm 2′ OH ntawm ceg chaw adenosine ntawm 5′ splice hlws ris. Thaum lub sij hawm splicing cov tshuaj tiv thaiv, pab pawg II introns tsim ib lub lariat zoo li cov qauv. Ntxiv mus, intron splicing tshwm sim thaum tsis muaj GTP.
Dab tsi zoo sib xws ntawm Pawg I thiab Pab Pawg II Introns?
- Pab pawg I thiab pab pawg II introns yog ob hom RNA enzymes, ribozymes uas ua rau lawv tus kheej sib txuas los ntawm cov txheej txheem sib txawv.
- Lawv yog cov ribozymes loj.
- Ob leeg pom nyob rau hauv tag nrho peb lub npe.
- Lawv yog cov khoom txawb.
- Ntxiv mus, lawv muaj nyob rau hauv rRNA, tRNA thiab protein-coding noob.
- Ob lub enzymes yog siv los ua cov cuab yeej hauv biotechnology thiab cov tshuaj molecular rau lub hom phiaj gene knock-out/knock-down, gene xa lossis gene therapy systems.
Qhov txawv ntawm Pawg I thiab Pawg II Introns yog dab tsi?
Pab pawg I introns yog ribozymes pom nyob rau hauv cov kab mob, bacteriophages thiab eukaryotic organellar thiab nuclear genomes. Pawg II introns yog ribozymes pom nyob rau hauv cov kab mob, archaea, thiab eukaryotic organelles. Ntxiv mus, pawg I introns pib splicing cov tshuaj tiv thaiv los ntawm nucleophilic nres ntawm 3′ hydroxyl ntawm ib tug guanosine cofactor ntawm 5P splice site thaum pab pawg II introns pib splicing cov tshuaj tiv thaiv los ntawm nucleophilic nres ntawm 2′ OH ntawm ceg chaw adenosine ntawm lub 5′ kev sib tshuam. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm pawg I thiab pawg II introns.
Tsis tas li ntawd, pawg II introns tsim ib lub lariat zoo li cov qauv thaum lub sij hawm sib txuas thaum pab pawg kuv introns tsis tsim. Yog li, qhov no yog lwm qhov sib txawv tseem ceeb ntawm pawg I thiab pawg II introns. Tsis tas li ntawd, pawg I introns muaj nyob rau hauv eukaryotic nuclear genomes thaum pab pawg II introns tsis pom nyob rau hauv eukaryotic nuclear genomes.
Hauv qab infographic teev qhov sib txawv ntawm pawg I thiab pab pawg II introns hauv daim ntawv teev npe rau ib sab ntawm kev sib piv.
Summary – Group I vs Group II Introns
Pab pawg I thiab II introns yog cov ribozymes loj uas ua rau cov tshuaj tiv thaiv transesterification rau splice tawm introns los ntawm thawj cov ntawv sau tseg. Lawv muaj nyob rau hauv tag nrho peb lub teb chaws. Lawv ob leeg yog mobile genetic ntsiab. Ntxiv mus, lawv tau siv los ua cov cuab yeej hauv biotechnology thiab tshuaj molecular. Txawm li cas los xij, pawg I introns pib splicing cov tshuaj tiv thaiv los ntawm kev tawm tsam nucleophilic ntawm 3' OH ntawm guanosine cofactor ntawm 5P splice site. Tab sis, pawg II introns pib splicing cov tshuaj tiv thaiv los ntawm nucleophilic nres ntawm 2′ OH ntawm ceg chaw adenosine ntawm 5′ splice hlws ris. Ntxiv mus, pawg II introns tsim ib lub lariat zoo li cov qauv thaum lub sij hawm splicing thaum pab pawg neeg kuv introns tsis tsim ib tug lariat zoo li qauv. Yog li, qhov no yog cov ntsiab lus ntawm qhov sib txawv ntawm pawg I thiab pawg II introns.
