DNA transpozoni u genomu čovjeka

undergraduate thesis

• Title (english): DNA transposons in the human genome
• Author: Zoe Jelić Matošević
• Mentor: Miroslav Plohl (mentor)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2016, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Transpozoni sačinjavaju oko 3% ljudskog genoma, no nisu bili aktivni zadnjih 37 milijuna godina. Kroz evoluciju primata njihova je aktivnost postepeno opadala, no u razdoblju prije divergencije suhonosaca i potom prije divergencije majmuna novog svijeta bili su vrlo aktivni. Unatoč ovome, mnogi geni derivirani iz njihovih sekvenci domesticirani su u ljudskom genomu, među kojima su možda najpoznatiji geni Rag1 i Rag2 nužni za adaptivnu imunost. Transpozaza prepoznaje transpozon pomoću njegovih ITR-ova, a sami mehanizmi izrezivanja razlikuju se među skupinama. Primjerice, precizno izrezivanje PiggyBac transpozona čini ga izuzetno pogodnim alatom za mutagenezu i vektorom za genomsko inženjerstvo i genetičku terapiju. Povećanje broja transpozona ovisno je o fazi staničnog ciklusa i zapravo se zasniva na popravku mjesta izrezivanja transpozona pomoću homologne sekvence u kojoj se taj isti transpozon još uvijek nalazi. Širenje transpozona kroz genom je ograničeno i domaćinovim mehanizmima obrane, kao i nakupljanjem mutaciju u samom transpozonu. Inaktivacija određenog transpozona je naposlijetku neizbježna, tako da proliferacija ovih genetičkih elemenata ovisi o kontinuiranoj infiltraciji genoma.

Abstract (english)

Transposons make up 3% of the human genome, but they have not been active for the past 37 million years. Their activity has declined steadily throughout the primate evolution, but a surge in their activity can be observed right before the divergence of prosimians, and later, before the divergence of New world monkeys. Although the transposons themselves are not active in the human genome any more, many genes made out of their domesticated sequences are functional. The best known example are the Rag1/Rag2 genes, essential for adaptive immunity. Transposase recognizes the transposon's TIRs, and the mechanisms of excision vary between different groups. The precise excision of the piggyBac transposon make it a useful tool for mutagenesis and an important vector for genomic engineering and gene therapy. Transposon multiplication is cell cycle-dependent. It is based on the repair of the donor sequence with a homologous template sequence that still contains the transposon. The spread of transposons through the genome is also limited by the host's defense mechanisms as well as the accumulation of mutations within the transposon. According to the life-cycle model, the inactivation of a class II transposable element is therefore inevitable, and so the proliferation of these elements depends upon the horizontal transfer.

• Keywords: transpozoni; genom
• Keywords (english): transposons; genome
• Language: croatian
• URN:NBN: urn:nbn:hr:217:424492
• 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: 2018-01-03 08:11:15