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Within this paper, reproduction traits of the Adriatic population European hake, Merluccius merluccius (Linnaeus, 1758), were investigated. Specimens of the target species were monthly collected (N=1173) during 2019 along the eastern Adriatic Sea with commercial bottom trawlers. Overall, European hake total body length varied between 15.5 and 49.5 cm (mean±SD=27.5±5.0 cm) and domination of females was noted in larger length classes (TL>31.0 cm). The sexual ratio of all specimens was m/f=0.64; male prevalence was established over the year, except during the spawning peaks (December, June) when the sex ratio was in favour of the females. According to European hake’s maturity stages, gonad weights, gonadosomatic indexes and histological analysis of the gonad tissues, this species in Adriatic spawn twice in one year; the spawning period was from December to February, while second smaller signs of spawning were observed at the beginning of the summer, in June. 50% of the European hake male and female specimens sexually matured at 20.7 cm and 22.4 cm of total length, respectively., U okviru ovog rada je istražena reproduktivna biologija jadranske populacije oslića, Merluccius merluccius (Linnaeus, 1758). Uzorci istraživane vrste su prikupljeni iz uzoraka lovina ostvarenih komercijalnom pridnenom mrežom koćom s područja istočnog Jadrana (Hrvatsko ribolovno more) jednom mjesečno (N = 1173) tijekom 2019. godine. Raspon totalnih dužina tijela oslića se kretao između u rasponu od 15,5 cm do 49,5 cm (srednja vrijednost ± SD = 27,5 ± 5,0 cm) te je pri većim dužinskim razredima zabilježena dominacija ženki (TL> 31,0 cm). Omjer spolova (m/ž) je iznosio 0,64; prevalencija mužjaka je utvrđena tijekom čitave godine izuzev razdoblja mrijesta (prosinac, lipanj) kada je omjer spolova bio u korist ženki. Analizom stadija zrelosti, mase gonada, gonadosomatskog indeksa te histoloških preparata tkiva spolnih žlijezda utvrđeno je da se ova vrsta u Jadranu mrijesti dva puta u jednoj godini; utvrđeno je razdoblje mrijesta od prosinca do veljače, dok je drugo razdoblje mrijesta nešto slabijeg intenziteta utvrđeno početkom ljeta, točnije u lipnju. Prva spolna zrelost svih analiziranih jedinki oslića je nastupila pri totalnoj dužini tijela od 20,7 cm za mužjake odnosno 22,4 cm za ženke.

Given the fundamental role of the MRE11 in many aspects of DNA metabolism and signaling in eukaryotes, we analyzed the impact of several MRE11 mutations on DNA damage response (DDR) and DNA repair in Arabidopsis thaliana. Three different atmre11 and an atatm-2 mutant lines, along with the wild-type (WT), were compared by a new -Arabidopsis genotoxic assay for in situ evaluation of the genome integrity and DNA damage repair efficiency after double strand break (DSB) induction. The results showed that, despite the phenotypic differences and the different lengths of the putative truncated AtMRE11 proteins, all three atmre11 and the atatm-2 mutant lines, exhibited common hypersensitivity to the bleomycin-treatment, upon which they reduced mitotic activities only slightly, indicating a G2/M checkpoint abrogation. In contrast to the WT which reduced the frequency of chromosomal aberrations through the recovery period after treatment, all three atmre11 and atatm-2 mutants did not recover. Moreover, atmre11-3 mutants, similarly to atatm-2 mutants, failed to transcriptionally induce several DDR genes and had altered expression of the CYCB1 ; 1::GUS protein. Nevertheless, numerous chromosomal fusions in the atmre11 mutants, observed after DNA damage induction, suggest intensive DNA repair activities. These results indicate that the functional and full-length AtMRE11 is essential for the activation of the cell cycle arrest, transcriptional regulation and the DNA repair upon the induction of DSBs.