THE ROLE OF de novo DNA METHYLATION IN PLANT RESPONSE TO ELEVATED TEMPERATURE

doctoral thesis

• Title (croatian): ULOGA de novo METILACIJE DNA U ODGOVORU BILJAKA NA POVIŠENU TEMPERATURU
• Author: Tokić Mirta
• Mentor: Nataša Bauer (mentor)
• Committee member: Mirta Tkalec (predsjednik povjerenstva)
• Committee member: Branka Salopek-Sondi (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2024-04-02, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology
• Universal decimal classification (UDC): 577 - Biochemistry. Molecular biology. Biophysics

Abstract

One of the key factors affecting plant survival and agricultural yield production is temperature. In this thesis, effects of prolonged 37 °C and short-term 45 °C heat treatments were investigated in Arabidopsis thaliana, Brassica rapa ssp. pekinensis and Solanum lycopersicum. Elevated temperatures negatively affected germination, development, shoot and root growth, and flower morphology. Seedlings and inflorescences were more thermosensitive than leaves of adult plants. Global DNA methylation levels and expression of key RNA-directed DNA methylation (RdDM) genes varied in different species, tissues and under heat stress. To evaluate the role of de novo DNA methylation in heat stress, different A. thaliana lines with altered RdDM pathway were used. DNA methylation at single-base resolution in AGL14, FBW2 and RKP genes and expression of RdDM-related genes revealed differences under heat stress, indicating the importance of an intact de novo DNA methylation machinery in thermotolerance.

Abstract (croatian)

Temperatura je jedan od ključnih čimbenika koji utječu na preživljavanje biljaka i poljoprivredne prinose. U ovom doktorskom radu istražen je utjecaj dugotrajnog izlaganja biljaka Arabidopsis thaliana, Brassica rapa ssp. pekinensis i Solanum lycopersicum temperaturi od 37 °C i kratkotrajnog izlaganja na 45 °C. Povišene su temperature negativno utjecale na klijavost, razvoj, rast izdanaka i korijena te morfologiju cvijeta. Klijanci i cvatovi bili su osjetljiviji na toplinski stres od listova odraslih biljaka. Globalne razine metilacije DNA i ekspresija ključnih gena uključenih u metilaciju DNA posredovanu malim RNA molekulama (RdDM) varirala je u različitim vrstama i tkivima te nakon izlaganja toplinskom stresu. Za procjenu uloge de novo metilacije DNA u toplinskom stresu korištene su različite linije A. thaliana u kojima je promijenjen put RdDM. Promjene u metilaciji gena AGL14, FBW2 i RKP te ekspresiji gena uključenih u RdDM uzrokovane toplinskim stresom ukazuju na važnost intaktnog de novo mehanizma metilacije DNA u toleranciji na povišenu temperaturu.

• Keywords: Arabidopsis thaliana; Brassica rapa ssp. pekinensis; de novo DNA methylation; heat stress; RdDM; Solanum lycopersicum; stress parameters
• Keywords (croatian): Arabidopsis thaliana; Brassica rapa ssp. pekinensis; de novo metilacija DNA; pokazatelji stresa; RdDM; Solanum lycopersicum; toplinski stres
• Language: english
• URN:NBN: urn:nbn:hr:217:801886
• Promotion: 2024
• Project: Number: IP-2016-06-6229; Title: MATH-BTB proteini kao regulatori transkripcije i RNA posredovane metilacije DNA u biljnom razvitku; Title: MATH-BTB proteins as switches between transcription and RNA-directed DNA methylation during plant development; Acronym: PHYTOMETHDEV; Leader: Dunja Leljak-Levanić; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Project: Number: IP-2014-09-4359; Title: Fitohormoni u abiotskom stresu kupusnjača: mehanizam tolerancije i primjena; Title: Phytohormones in abiotic stress of Brassica crops: mechanism of tolerance and application; Acronym: PhytoBraCro; Leader: Branka Salopek-Sondi; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Project: Number: KK.05.1.1.02.0005; Title: Agrobioraznolikost - osnova za prilagodbu i ublažavanje posljedica klimatskih promjena u poljoprivredi; Acronym: Agrobioclim; Leader: Smiljana Goreta Ban; Jurisdiction: Croatia; Funder: Europska komisija
• Project: Number: Project-ID 57560291; Title: Uloga auksin amidohidrolaza uročnjaka (Arabidopsis thaliana) u toplinskom stresu; Leader: Jutta Ludwig-Müller i Branka Salopek Sondi; Jurisdiction: Croatia; Funder: DAAD i MZO
• Study programme: Title: Doctoral study; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti u području prirodnih znanosti (doktor/doktorica znanosti u području prirodnih znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2026-04-02
• Created on: 2024-04-15 11:09:03