Evolucija i funkcija traspozona MT, specifičnih za glodavce

doctoral thesis

• Title (english): Evolution and function of rodent specific MT transposons
• Author: Vedran Franke
• Mentor: Kristian Vlahoviček (mentor)
• Committee member: Nenad Malenica (predsjednik povjerenstva)
• Committee member: Helena Ćetković (član povjerenstva)
• Committee member: Petra Svoboda (član povjerenstva); MBZ: 333151
• 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
• Universal decimal classification (UDC): 57 - Biological sciences. Physical anthropology. Biodiversity

Abstract

Retrotranspozoni MT pripadaju klasi LTR retrotranspozona, prisutnih isključivo kod glodavaca. Nakon retrotranspozona SINE i LINE, MT elementi su treći najučestaliji ponavljajući elementi u genomima glodavaca. Za razliku od klasičnih LTR retrotranspozona sisavaca, sekvenca između LTR krajeva kod MT elemenata nije homologna retroviralnim GAG, POL i PRO proteinima, već sadržava niz regulatornih sekvenci. One MT elementima omogućavaju tkivno - specifično reprogramiranje transkriptoma a time i doprinos u regulaciji genske ekspresije. MT elementi dijele se u pet skupina, MTA – MTE. MTC element u intronu 6 gena Dicer 1, stvara oocitno specifičnu, skraćenu izoformu proteina – nazvanu DicerO. Takav skraćeni protein pokazuje veću procesivnost malih interferirajućih RNA molekula (siRNA) u usporedbi sa somatskom izoformom proteina, DicerS. Ciljano uklanjanje elementa MTC iz introna 6 gena Dicer 1 ima za posljedicu poremećaje u organizaciji diobenog vretena i sterilnost ženki miševa, iz čega proizlazi da je MTC element esencijalni dio genoma miša. U ovom radu opisao sam podrijetlo, širenje i funkcionalnu ulogu (funkciju) retrotranspozona MT u liniji glodavaca.

Abstract (english)

MT retrotransposons are LTR retrotransposons found specifically in the rodent lineage. After SINE and LINE retrotransposons, MT elements are the third most abundant repetitive class in the rodent genomes. Unlike classical mammalian LTR retrotransposons, the internal sequence of MT elements lacks homology to the retroviral GAG, POL and PRO proteins; rather it contains sets of regulatory sequences. These regulatory sequences enable MT elements to reprogram the transcriptome in an oocyte-specific manner. MT elements are subdivided into five groups, MTA – MTE. An MTC element in the intron 6 of the Dicer 1 gene creates an oocyte specific, truncated Dicer isoform – DicerO. Such truncated isoform has higher processivity for small interfering RNAs, when compared to the somatic isoform, DicerS. Targeted excision of the MTC causes meiotic spindle deformation and female sterility, thereby illustrating its essential function of the retroelement for in mice. In this work I have described the origin and exaptation of MT elements in the rodent lineage.

• Keywords: Retrotranspozon; MT; Oocita; miRNA; siRNA
• Keywords (english): Retrotransposon; MT; Oocyte; miRNA; siRNA
• Language: croatian
• URN:NBN: urn:nbn:hr:217:258467
• Study programme: Title: Biology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje biologija (doktor/doktorica znanosti, područje prirodnih znanosti, polje biologija)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-12 10:25:29