Qhov sib txawv tseem ceeb ntawm snRNA thiab snRNP yog tias snRNAs yog me me nuclear RNA molecules thaum snRNPs lossis me me nuclear ribonucleoproteins yog me me nuclear RNA molecules nrog cov proteins.
snRNAs tsis yog-coding, lom lom RNA molecules nrog qhov nruab nrab loj ntawm 150 nucleotides. Lawv feem ntau muaj nyob rau hauv koom nrog cov proteins li snRNPs hauv lub xeev ntuj. Li no, snRNPs yog me me nuclear RNA nrog ob peb snRNP cov proteins tshwj xeeb. snRNPs koom nrog hauv kev sib kho los yog tswj cov txheej xwm tom qab kev txhais lus RNA-txheej xwm xws li splicing, thiab lwm yam. Ob leeg snRNA thiab snRNP muaj nyob rau hauv lub nucleus ntawm eukaryotic hlwb.
snRNA yog dab tsi?
snRNA sawv cev rau me me nuclear RNA. Lawv yog cov me me nuclear RNA molecules pom nyob rau hauv splicing speckles thiab Cajal lub cev ntawm lub cell nucleus nyob rau hauv eukaryotic hlwb. Ib qho snRNA molecule muaj qhov nruab nrab ntev ntawm 150 nucleotides. Cov snRNAs no tau sau los ntawm pol II thiab pol III. Lub luag haujlwm tseem ceeb ntawm snRNA yog kev ua haujlwm ntawm pre-messenger RNA (hnRNA) hauv lub nucleus. Lawv feem ntau koom nrog hauv kev kho kom haum xeeb lossis tswj hwm kev hloov pauv tom qab RNA-ua cov txheej xwm xws li splicing. Vim yog snRNAs kev ua, kev sib dhos meej thiab raug txiav tawm ntawm introns tshwm sim. Tsis tas li ntawd, snRNAs koom nrog kev tswj hwm ntawm cov xwm txheej hloov pauv (7SK RNA) lossis RNA polymerase II (B2 RNA) thiab tswj telomeres.
Figure 01: snRNA
snRNAs tsis yog-coding RNAs. Lawv nyob rau hauv chav kawm uas muaj ntau yam kev lom zem RNA nyob hauv lub nucleus. Lawv yeej ib txwm txuam nrog cov protein molecules thiab muaj raws li me me nuclear ribonucleoproteins (snRNP). Muaj ob lub ntsiab ntawm snRNAs li Sm-class snRNA thiab Lsm-class snRNA. U1, U2, U4, U4atac, U5, U7, U11, thiab U12 yog Sm-class snRNA thaum U6 thiab U6atac yog Lsm-class snRNA.
snRNP yog dab tsi?
snRNP yog ib qho me me nuclear RNA molecule ua ke nrog cov proteins. Feem ntau, txhua snRNP muaj ib qho snRNA thiab ntau cov protein molecules. Yog li ntawd, snRNPs yog me me nuclear RNA molecules thiab cov proteins. snRNPs, ua ke nrog ntau lwm cov proteins ntxiv, tsim cov complex hu ua spliceosome qhov twg RNA splicing tshwm sim. snRNPs xav tau ob qho tib si RNA ib feem thiab cov protein kom sib cais tawm introns. RNA tivthaiv yog lub luag haujlwm rau kev txiav cov endonuclease vim nws muaj cov haujlwm enzymatic. Muaj ntau hom snRNPs, thiab lawv txiav ntawm qhov chaw sib txawv.
Daim duab 02: snRNP hauv Spliceosome
Ntxiv rau kev sib txuas, snRNPs koom nrog hauv kev loj hlob ntawm cov ntaub ntawv tseem ceeb hauv mRNAs, cov kev cai ntawm cov noob caj noob ces, splice pub dawb hauv cov tshuab tsis-canonical thiab hauv 3'-kawg ua ntawm replication-dependent histone mRNAs. Muaj ob pawg tshwj xeeb ntawm snRNPs ua cov nucleolar RNPs me me (snoRNPs) thiab me me Cajal-body RNPs (scaRNPs).
Dab tsi zoo sib xws ntawm snRNA thiab snRNP?
- Ob leeg snRNA thiab snRNP muaj me me nuclear RNA molecules.
- snRNAs ua ke nrog cov proteins los ua snRNPs.
- Txhua snRNP muaj ib qho snRNA.
- Ob leeg snRNA thiab snRNP muaj nyob rau hauv lub nucleus ntawm eukaryotic hlwb.
Qhov txawv ntawm snRNA thiab snRNP yog dab tsi?
snRNA yog ib qho me me uas tsis yog-coding RNA molecule nyob hauv lub eukaryotic cell nucleus thaum snRNP yog ib qho nyuaj ntawm ib qho snRNA thiab snRNP cov proteins tshwj xeeb. snRNPS yog me me nuclear ribonucleoprotein hais. snRNA tsuas yog ib qho me me RNA molecule thaum snRNP yog ib qho nyuaj ntawm snRNA molecule thiab nruj nreem khi cov proteins. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm snRNA thiab snRNP.
Hauv qab infographic qhia qhov sib txawv ntawm snRNA thiab snRNP hauv daim ntawv tabular.
Summary – snRNA vs snRNP
snRNA yog ib chav kawm ntawm cov tsis-coding me me nuclear RNA nyob rau hauv lub eukaryotic nucleus. Lawv ua tiav cov haujlwm tseem ceeb ntsig txog intron splicing thiab lwm yam RNA ua. Nyob rau hauv lub xeev ntuj, snRNA yog txuam nrog cov proteins thiab muaj raws li me me nuclear ribonucleoprotein hais (snRNPs).snRNPs, ua ke nrog ntau lwm cov proteins, tau koom nrog hauv kev tsim cov spliceosome complex thiaj li ua tiav RNA splicing. Yog li, qhov no qhia txog qhov sib txawv ntawm snRNA thiab snRNP.
