Qhov sib txawv tseem ceeb ntawm LINEs thiab SINEs yog tias LINEs (ntev interspersed nuclear ntsiab) yog ib hom ntev uas tsis yog-LTR retrotransposons thaum SINEs (luv interspersed nuclear ntsiab) yog hom luv luv uas tsis yog-LTR retrotransposons.
Non-LTR retrotransposons tsis muaj cov davhlau ya nyob twg ntev (LTR). Txawm li cas los xij, lawv muaj cov noob rau thim rov qab transcriptase, RNA binding protein, nuclease, thiab ribonuclease H domain. Non-LTR retrotransposons muaj luv luv rov ua dua. Cov kev rov ua dua no muaj qhov kev txiav txim rov qab ntawm lub hauv paus ntawm ib sab. Tsis tas li ntawd, tsis yog-LTR retrotransposons kuj tseem muaj kev rov qab ncaj qha pom hauv LRT transposons. Non-LTR retrotransposons poob rau hauv ob pawg raws li LINEs thiab SINes.
LINE yog dab tsi?
LINEs (ntev interspersed nuclear ntsiab) yog ntev dua tsis-LTR retrotransposons. Lawv nthuav dav hauv cov genomes ntawm eukaryotes. Lawv feem ntau ua 21.1% ntawm tib neeg genome. Txhua kab yog nyob ib ncig ntawm 7000 lub hauv paus khub ntev. LINEs tuaj yeem sau rau hauv mRNA thiab txhais ua cov protein uas tuaj yeem ua haujlwm raws li qhov rov qab transcriptase enzyme. Qhov rov qab transcriptase no ua rau DNA luam ntawm LINEs RNA. Cov ntawv luam DNA no tuaj yeem muab tso rau hauv genome ntawm qhov chaw tshiab.
Daim duab 01: LINEs thiab SINEs
Tus tib neeg genome tsuas muaj ib qho LINE uas muaj npe hu ua LINE-1. LINE-1 lub caij yog nyob ib ncig ntawm 6000 lub hauv paus khub ntev. Muaj nyob ib ncig ntawm 100, 000 LINE-1 truncated ntsiab nyob rau hauv tib neeg genome. Random kev hloov pauv tuaj yeem tshwm sim hauv LINEs. Vim muaj kev hloov pauv tsis sib xws, LINEs tuaj yeem degenerate. Lawv tsis tau sau los yog txhais lawm. Tsis tas li ntawd, LINEs tau muab faib ua tsib pawg xws li L1, RTE, R2, I thiab jockey. tsib pawg no ntxiv subdivided rau lwm 28 clades.
LINEs ib txwm nthuav tawm los ntawm lub tshuab hu ua lub hom phiaj primed thim rov qab cov txheej txheem (TPRT). Kev tso cov LINEs ua rau tib neeg muaj kab mob xws li haemophilia A, mob qog noj ntshav, mob mendelian, thiab lwm yam. Hypomethylation ntawm LINEs kuj ua rau qee yam mob qog noj ntshav.
SIN yog dab tsi?
SINEs (cov ntsiab lus luv luv interspersed nuclear) yog hom luv luv uas tsis yog LTR retrotransposons. Lawv muaj li ntawm 100 mus rau 700 lub hauv paus khub ntev. SINEs kuj yog cov ntsiab lus DNA uas ua rau lawv tus kheej thoob plaws hauv eukaryotic genomes los ntawm RNA intermediates. SINs tsim txog li 13% ntawm cov tsiaj txhu genome. Cov cheeb tsam sab hauv ntawm SINs yog los ntawm tRNA. Nws tseem txuag tau heev. Lawv feem ntau muaj nyob rau hauv ntau hom vertebrates thiab invertebrates. Daim ntawv luam tus lej sib txawv thiab kev hloov pauv hauv SINEs tuaj yeem suav nrog los tsim cov phylogeny-raws li kev faib tawm ntawm hom.
SINEs tuaj yeem muab faib ua peb hom: CORE-SINEs, V-SINEs, thiab AmnSINEs. Alu keeb yog SINE feem ntau hauv primates. Ntxiv mus, muaj ntau tshaj 50 tib neeg cov kab mob cuam tshuam nrog kev tso ntawm SINEs. Thaum lawv ntxig rau hauv lossis ze ntawm exons, lawv tuaj yeem ua rau tsis raug splicing lossis hloov cov ntawv nyeem. Qhov no ua rau cov kab mob phenotypes xws li mob qog noj ntshav mis, mob qog noj ntshav, mob ntshav qab zib, mob haemophilia, cystic fibrosis, mob qog noj ntshav, Dent's kab mob, neurofibromatosis, thiab lwm yam.
Dab tsi yog qhov zoo sib xws ntawm LINEs thiab SINEs?
- LINEs thiab SINEs yog ob hom tsis-LTR retrotransposons.
- Ob leeg tsis muaj thaj tsam ntev (LTR).
- Ob leeg feem ntau pom tsuas yog hauv eukaryotes.
- Lawv ob leeg tsis yog tus kheej.
Qhov txawv ntawm LINEs thiab SIN yog dab tsi?
LINEs ntev dua tsis yog-LTR retrotransposons, thaum SINs luv dua tsis yog-LTR retrotransposons. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm LINEs thiab SINEs. Tsis tas li ntawd, LINES code rau thim rov qab transcriptase enzyme, thaum SINE tsis code rau thim rov qab transcriptase enzyme. Yog li, qhov no yog lwm qhov sib txawv ntawm LINEs thiab SINes.
Ntau qhov sib txawv ntawm LINEs thiab SINEs tau teev tseg hauv qab no hauv daim ntawv teev npe rau ib sab ntawm kev sib piv.
Summary – LINEs vs SINES
Retrotransposons feem ntau pom nyob rau hauv tag nrho cov eukaryotes tab sis tsis nyob hauv prokaryotes. Kwv yees li, 37% ntawm tib neeg genome muaj retrotransposons. Retrotransposons feem ntau yog ob hom: LTR thiab Non-LTR retrotransposons. Tsis yog-LTR retrotransposons tsis muaj cov davhlau ya nyob twg ntev (LTR), uas muaj nyob hauv LTR retrotransposons. Non-LTR retrotransposons tau muab faib ua ob pawg: LINEs thiab SINEs. Cov kab yog ntev dua uas tsis yog-LTR retrotransposons, thaum SINEs yog luv dua tsis-LTR retrotransposons. Yog li, qhov no yog cov ntsiab lus ntawm qhov sib txawv ntawm LINEs thiab SINEs.
