Uloga metilacije DNA tijekom embrionalnog razvoja životinja

undergraduate thesis

• Title (english): The role of DNA methylation during embryonic development of animals
• Author: Nina Ivanković
• Mentor: Gordana Lacković-Venturin (mentor)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2014, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

DNA metilacija provodi se DNA metiltransferazama 1, 3a i 3b. Dnmt1 omogućava nasljeđivanje metilacijskog uzorka sa „starog“ na novosintetizirani lanac DNA tijekom svake DNA replikacije. Dnmt 3a i 3b uspostavljaju novi metilacijski uzorak putem vlastite de novo metiltransferazne aktivnosti. Dnmt1, 3a i 3b esencijalni su tijekom razvoja jer je njihovom delecijom inhibiran razvoj embrija, a uslijed njihove mutacije ili mutacije proteina s kojima surađuju, priječi se normalan razvoj i uzrokuju teški poremećaji. Metilacijom DNA u kromatinsku strukturu uvodimo promjene koje onemogućavaju enzimima, transkripcijskim faktorima itd., pristup DNA. Onemogućavanje pristupa DNA dovodi do utišavanja genske ekspresije, ali, kao što smo vidjeli na primjeru genomskog utiska, DNA metilacijom možemo i potaknuti gensku ekspresiju. DNA metilacija stoga, tijekom embrionalnog razvoja, omogućava staničnu diferencijaciju, formiranje genomskog utiska u germinativnim stanicama, ekspresiju utisnutih gena u stanicama na različitom stupnju diferencijacije, inaktivaciju X kromosoma u ženki te inaktivaciju pokretnih genetičkih elemenata.

Abstract (english)

DNA methylation is carried out by DNA methyltransferases 1, 3a and 3b. Dnmt1 ensures that DNA methylation pattern is maintained after each cell division. Dnmt3a and Dnmt3b are responsible for establishment of new DNA methylation pattern by their de novo methytransferase activity. Dnmt 1, 3a and 3b are known to be essential during embryonic development because targeted deletion of any one of them leads to developmental arrest at early stages of development and because mutations in Dnmt or proteins that cooperate with Dnmt impair normal development leading to severe disorders. DNA methylation changes the chromatin structure and with it changes the accessibility of DNA which leads to gene silencing or activation of gene expression, showed by the example of imprinted genes. Changes mentioned above, caused by DNA methylation, are known to be involved in cellular differentiation, formation of genomic imprinting in germ cells, expression of imprinted genes in cells on different differentiation levels, X chromosome inactivation and silencing of mobile genetic elements.

• Keywords: DNA metilacija; embrionalni razvoj životinja
• Keywords (english): DNA methylation; embryonic development of animals
• Language: croatian
• URN:NBN: urn:nbn:hr:217:119301
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) molekularne biologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-12-08 09:40:38