Učinak UVB-zračenja na uročnjak (Arabidopsis thaliana (L.) Heynh.) s promijenjenom ekspresijom gena BPM

master's thesis

• Title (english): Effect of UV-B radiation on thale cress (Arabidopsis thaliana (L.) Heynh.) with modified BPMs expression
• Author: Antonija Tandara
• Mentor: Željka Vidaković-Cifrek (mentor)
• Committee member: Željka Vidaković-Cifrek (predsjednik povjerenstva)
• Committee member: Dunja Leljak-Levanić (član povjerenstva)
• Committee member: Marin Ježić (član povjerenstva)
• Committee member: Biljana Balen (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2022-02-22, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Sunčevo zračenje je izvor energije za fotosintezu i važan signal za regulaciju rasta i razvoja
biljaka. Međutim, svjetlost visokog intenziteta, a posebno ultraljubičasti zračenje, može
izazvati stres u biljaka. Mjerenjem količine H2O2, prolina, stupnja lipidne peroksidacije,
aktivnosti antioksidacijskih enzima i učinkovitosti fotosinteze moguće je procijeniti učinak
stresnih uvjeta na biljke. Cilj ovog istraživanja bio je procijeniti učinak UVB-zračenja na
modelnu biljku Arabidopsis thaliana. Osim divljeg tipa, koristila sam linije oeBPM1 i
amiR-bpm koje imaju promijenjenu ekspresiju gena BPM. Protein BPM1 pripada porodici
proteina MATH-BTB (BPM) koji u biljci sudjeluju u razvojnim procesima i odgovoru na
stresne uvjete. Imunodetekcijom proteina BPM1-GFP u linije oeBPM1 potvrdila sam
akumulaciju tog proteina nakon izlaganja dozi UV-zračenja od 831 J cm-2
. Primjenom te doze
UVB-zračenja i usporedbom kontrolnih i tretiranih biljaka potvrdila sam razliku u količini
H2O2 u biljaka divljeg tipa i liniji oeBPM1, u aktivnosti gvajakol peroksidaze i superoksid
dismutaze u biljaka divljeg tipa te u maksimalnom kvantnom prinosu PSII u liniji oeBPM1.
Veću razliku uočila sam između linija nego između kontrolnih i tretiranih biljaka. Linija
oeBPM1 pokazala je bolji odgovor na stres u odnosu na druge dvije linije zbog izrazitije
aktivacije antioksidacijskih enzima, dok je linija amiR-bpm imala višu razinu H2O2 i lipidne
peroksidacije u odnosu na divlji tip i liniju oeBPM1. Budući da se navedene linije razlikuju u
ekspresiji gena BPM, moguća je njihova uključenost u odgovor na UVB-zračenje.

Abstract (english)

Solar radiation is a source of energy for photosynthesis and an important signal for regulation
of plant growth and development. However, high light intensity, and especially ultraviolet
radiation, can cause stress in plants. H2O2 and proline content, lipid peroxidation level, activity
of antioxidant enzymes and efficiency of photosynthesis are measurable parameters for
assessing the stress effect on plants. The main goal of the research was to evaluate the effect
of UV-B radiation on model plant Arabidopsis thaliana. Besides wild-type, the lines with
modified expression of BPM genes (oeBPM1 and amiR-bpm) were used. BPM1 protein
belongs to the MATH-BTB (BPM) protein family that participate in developmental processes
and stress response in plants. Immunodetection of BPM1-GFP protein in oeBPM1 confirmed
the highest accumulation of the protein after treatment with UV-B radiation dose of 831 J cm-2
.
The comparison of control and treated plants showed that this dose of UV-B radiation induced
changes in the content of H2O2 in wild type and oeBPM1, in guaiacol peroxidase and
superoxide dismutase activity in wild type, and in the maximum quantum efficiency of PSII in
oeBPM1. Moreover, a difference between tested lines was more pronounced than difference
between control and treated plants of the same line. The oeBPM1 line showed better stress
response than other two lines due to more pronounced activation of antioxidant enzymes, while
the amiR-bpm line had higher H2O2 content and lipid peroxidation level compared to wild type
and oeBPM1. Because these lines differ in expression of BPM genes, their involvement in the
UV-B radiation response is possible.

• Keywords: antioksidacijski enzimi; linija amiR-bpm; linija oeBPM1; lipidna peroksidacija; OJIP-test; proteini MATH-BTB; vodikov peroksid
• Keywords (english): amiR-bpm line; antioxidant enzymes; hydrogen peroxide; lipid peroxidation; MATH-BTB proteins; oeBPM1 line; OJIP test
• Language: croatian
• URN:NBN: urn:nbn:hr:217:035924
• Study programme: Title: Molecular Biology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra molekularne biologije (magistar/magistra molekularne biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-03-23 12:39:20