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Arakelyan, M.

Publications and source records attributed to Arakelyan, M..

2 recordsLinked to original sources

A de novo reference genome of the golden jackal, Canis aureus

The golden jackal (Canis aureus) is rapidly expanding its range in Europe, driven by climate and habitat changes, human influence, and changes in competition with wolves. Its ecological flexibility enables it to thrive in various habitats, including urban areas, raising concerns about its potential role in spreading zoonotic diseases. Jackals may act as reservoirs for pathogens such as Lyme disease and babesiosis, affecting wildlife, humans, and pets. Their close genetic relationship with domestic dogs also increases the risk of hybridization and host-jumping, complicating disease dynamics. To better understand their dispersal ability and host-pathogen dynamics, we present the first chromosome-level genome assembly of the golden jackal, generated using PacBio HiFi sequencing and reference-based scaffolding. The final assembly has a total length of 2.53 Gb in 325 scaffolds, with 98.41% of the sequence anchored to the expected 38+XY chromosomes. The assembly shows high contiguity, with scaffold and contig N50 values of 68.03 Mb and 56.64 Mb, respectively. Annotation revealed 26,084 protein-coding genes, and repetitive elements account for 40.58% of the total assembly. This high-quality reference genome provides an essential resource for studying the genetic basis of the golden jackals adaptation, ecological interactions, and potential as a zoonotic reservoir. It also supports efforts to monitor population expansion and its effects on ecosystems. By advancing our understanding of golden jackal genetics, this work enables future research on evolution, host-pathogen dynamics, and the broader consequences of wildlife dispersal in a rapidly changing environment.

genomics↗

Premeiotic endoreplication is the mechanism of obligate parthenogenesis in rock lizards of the genus Darevskia

Among vertebrates, obligate parthenogenesis occurs exclusively in squamate reptiles. Premeiotic endoreplication in a small subset of developing oocytes has been documented as the mechanism of production of unreduced eggs in minutely explored obligate parthenogenetic lineages, namely in teiids and geckos. The situation in the lacertid genus Darevskia has been discussed for decades. Certain observations suggested that ploidy level is restored during egg formation through a fusion of egg and polar body nuclei in D. unisexualis and D. armeniaca. In this study, we re-evaluated the fusion hypothesis by studying diplotene chromosomes in adult females of sexual species D. raddei nairensis and obligate parthenogens D. armeniaca, D. dahli and D. unisexualis. We revealed 19 bivalents in the sexual species and 38 bivalents in the diploid obligate parthenogens, which uncovers premeiotic endoreplication as the mechanism of the production of non-reduced eggs in parthenogenetic females. The earlier contradicting reports can be likely attributed to the difficulty in identifying mispairing of chromosomes in pachytene, and the fact that in parthenogenetic reptiles relying on premeiotic endoreplication only a small subset of developing oocytes undergo genome doubling and overcome the pachytene checkpoint. This study highlights co-option of premeiotic endoreplication for escape from sexual reproduction in all independent hybrid origins of obligate parthenogenesis in vertebrates studied to date.

evolutionary biology↗