Utjecaj hladnog stresa i bakterijskih infekcija na ekspresiju satelitskih DNA u kukcima Tribolium castaneum i Drosophila melanogaster

master's thesis

• Title (english): Influence of cold stress and bacterial infection on satellite DNA expression in insects Tribolium castaneum and Drosophila melanogaster
• Author: Anamarija Pulitika
• Mentor: Đurđica Ugarković (mentor)
• Committee member: Jasmina Rokov Plavec (predsjednik povjerenstva)
• Committee member: Branimir Bertoša (član povjerenstva)
• Committee member: Iva Juranović Cindrić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2019-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Satelitsku DNA čine uzastopno ponavljajući sljedovi DNA koji se uglavnom nalaze u
centromernom, pericentromernom i telomernom dijelu heterokromatina i zauzimaju značajan
dio genoma u eukariotskom organizmu. U brašnaru Tribolium castaneum, okarakterizirane su
glavna (TCAST1) i sporedna satelitska DNA (TCAST2) čiji su elementi pronađeni raspršeni
unutar eukromatina u blizini jedinstvenih gena. U vinskoj mušici Drosophila melanogster,
okarakterizirana je glavna satelitska DNA (1.688) čiji su elementi također raspršeni unutar
eukromatina. Transkripti satelitskih DNA procesiraju se u male interferirajuće molekule RNA
(siRNA) koje mogu imati utjecaj na epigenetsko stanje heterokromatina. Dokazano je da je
ekspresija satelitskih elemenata TCAST osjetljiva na temperaturu, što upućuje na to da je
moguća njihova uloga u regulaciji ekspresije gena pod utjecajem stresa. Hladni stres, za
razliku od toplinskog, nije pokazao utjecaj na ekspresiju satelitskih DNA. Bakterijske
infekcije mogu dovesti do smanjenja ekspresije satelitskih DNA, ovisno o načinu infekcije,
prethodnoj imunizaciji i vrsti bakterije.

Abstract (english)

Satellite DNA are tandemly repeated DNA sequences that constitute a considerable part of
eukaryotic genome and are mostly present in centromeric, pericentromeric and subtelomeric
regions of heterochromatin. In the beetle Tribolium castaneum, major (TCAST1) and minor
(TCAST2) satellite DNA whose elements are found dispersed in the vicinity of unique genes
within euchromatin are characterized. In the fruit fly Drosophila melanogaster, elements of
major satellite DNA (1.688) are also found dispersed within euchromatin. Transcripts of
satellite DNA are processed into small interfering RNA (siRNA) that might affect the
epigenetic state of heterochromatin. Expression of elements of satellite DNA seems to be
highly sensitive to temperature and might play a role in the regulation of gene expression
under stress condition. Unlike heat shock, cold stress did not show effect on satellite
expression. Bacterial infection may lead to decreased expression of satellite DNA, but it
depends on many factors, such as infection routes, priming or bacterial species.

• Keywords: bakterijska infekcija; hladni stres; satelitska DNA
• Keywords (english): bacterial infection; cold stress; satellite DNA
• Language: croatian
• URN:NBN: urn:nbn:hr:217:470397
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2021-09-30
• Created on: 2019-10-02 12:18:56