Naslov
The role of MRE11 in activating cellular response after introduction of DNA double- strand breaks in Arabidopsis thaliana (L.) Heynh.

Autori
Šamanić, Ivica ; Cvitanić, Ratko ; Puizina, Jasna , Riha, Karel

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts of the 3rd Congress of Croatian Geneticists with international participation / Franketić, Jasna ; Garaj-Vrhovac, Verica - , 2012, 37-37

ISBN
978-953-57128-0-0

Skup
3rd Congress of Croatian Geneticists with international participation

Mjesto i datum
Krk, Hrvatska, 13.05.2012. - 16.05.2012

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
MRE11; Arabidopsis thaliana; Mitosis; DNA double-strand breaks; Cell cycle delay

Sažetak
The aim of this study was to investigate the possible role of MRE11 in the DNA damage signaling and cell cycle control in Arabidopsi thaliana. We have taken a new cytogenetic approach to analyze the mitotic activity and chromosomal abnormalities after DNA double strand breaks (DSBs) introduction. Inflorescences of A. thaliana were cut off and treated with bleomycin – mutagen known to induce the DSBs and mitosis were analyzed from pistil cells after 24, 48 and 72 hours recovery periods. We have monitored the behavior of three mre11 mutant lines that harbored T-DNA insertions in different parts of the gene and compared their response with wild-type (wt) and atm mutant line. The ATM protein is known to play a central role in cells' response to DNA damage. We obtained following results: 1) wt plants showed reduced mitotic activity coupled with extensive chromosome abnormalities after 24 hours of recovery, but mitotic activity reached nearly normal level after the 72 hours of recovery period, with also lower rate of chromosomal abnormalities 2) all three mre11 mutant lines showed no reduction in mitotic activities in spite of extensive chromosome fusions and fragmentation 3) atm mutant line mirrored the behavior of mre11 mutants. Obviously, in mre11 and atm mutants cell cycle arrest was abrogated and lesions were not properly repaired. These observations have been additionally confirmed by the results of RT- PCR. Bleomycin-treated mre11 and atm mutants in comparison with wt plants, had lower expression of genes involved in: cell cycle control (CYCB1 ; 1, WEE1, KNOLLE), DNA damage signaling (MRE11, ATM, ATR) and repair (RAD51, BRCA1, SYN2, PARP1). Taken together these results support our assumption that MRE11 gene is involved in DNA damage signaling and plant cell cycle control.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

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