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Esmailizadeh, A.

Publications and source records attributed to Esmailizadeh, A..

5 recordsLinked to original sources

Rapid evolution of fine-scale recombination during domestication

Recombination serves as a pivotal force propelling the evolution of genomic diversity in sexually reproducing organisms. Despite its fundamental role, the evolutionary dynamics of recombination rates and their implications for genome evolution remain largely elusive. The domestication of animals, which is characterized by dynamic selection pressures, offers a unique lens to explore this issue. Here, we constructed a fine-scale recombination map leveraging whole-genome data from domestic chickens, encompassing both contemporary commercial breeds and the wild progenitor, the Red Junglefowl (RJF). Our analysis revealed the rapid evolution of the recombination landscape within and across chicken populations, with significant variation in recombination coldspots and hotspots, particularly in commercial breeds. The occurrence of coldspots and the disappearance of hotspots are closely associated with selective sweeps.Contrary to prevailing observations in most species, we observed a weakly negative correlation between recombination rates and the frequency of introgressed ancestry from other RJF subspecies. Our findings provide valuable insights into the intricate interplay of evolutionary forces shaping the evolution of recombination.

evolutionary biology↗

Whole-genome sequence analysis unveils different origins of European and Asiatic mouflon and domestication-related genes in sheep

The domestication and subsequent development of sheep are crucial events in the history of human civilization and the agricultural revolution. However, the impact of interspecific introgression on the genomic regions under domestication and subsequent selection remains unclear. Here, we analyze the whole genomes of domestic sheep and all their wild relative species. We found introgression from wild sheep such as the snow sheep and its American relatives (bighorn and thinhorn sheep) into urial, Asiatic and European mouflons. We observed independent events of adaptive introgression from wild sheep into the Asiatic and European mouflons, as well as shared introgressed regions from both snow sheep and argali into Asiatic mouflon before or during the domestication process. We revealed European mouflons arose through hybridization events between a now extinct sheep in Europe and feral domesticated sheep around 6,000 - 5,000 years BP. We also unveiled later introgressions from wild sheep to their sympatric domestic sheep after domestication. Several of the introgression events contain loci with candidate domestication genes (e.g., PAPPA2, NR6A1, SH3GL3, RFX3 and CAMK4), associated with morphological, immune, reproduction or production traits (wool/meat/milk). We also detected introgression events that introduced genes related to nervous response (NEURL1), neurogenesis (PRUNE2), hearing ability (USH2A) and placental viability (PAG11 and PAG3) to domestic sheep and their ancestral wild species from other wild species.

evolutionary biology↗

The origin of domestication genes in goats

Goat domestication was critical for agriculture and civilization, but its underlying genetic changes and selection regimes remain unclear. Here we analyze the genomes of worldwide domestic goats, wild caprid species and historical remains, providing evidence of an ancient introgression event from a West Caucasian tur-like species to the ancestor of domestic goats. One introgressed locus with a strong signature of selection harbors the MUC6 gene which encodes a gastrointestinally secreted mucin. Experiments revealed that the nearly fixed introgressed haplotype confers enhanced immune resistance to gastrointestinal pathogens. Another locus with a strong signal of selection may be related to behavior. The selected alleles at these two loci emerged in domestic goats at least 7,200 and 8,100 years ago, respectively, and increased to high frequencies concurrent with the expansion of the ubiquitous modern mitochondrial haplogroup A. Tracking these archaeologically cryptic evolutionary transformations provides new insights into the mechanism of animal domestication. One Sentence SummaryGoat domestication mainly focused on immune and neural genes, with adaptive leaps driven by introgression and selection.

genomics↗

Canine transmissible venereal tumor genome reveals ancient introgression from coyotes to arctic sled dogs

Dear Editor,\n\nAncient genome-sequencing studies have extensively refined our understanding of the genetic histories and adaptive evolution of humans1, as well as the domestic process of livestock and crops2. Recent studies about ancient and modern canids all indicate that canids have intricate histories, and lots of canine populations disappeared during evolution3-6. Thus, ancient genomes from canine fossils are in high demand to clarify canine evolution and the processes leading to dog domestication. Canine transmissible venereal tumor (CTVT), the oldest known somatic cell line, is a living fossil, originating from cancer cells transmitted from a host to other canids during the mating process7. Clonal origin analyses hints that the original dog infected with CTVT (CTVT founder) came from an ancient sled dog or wolf population ...

evolutionary biology↗

Evolutionary history of the brown rat: out of southern East Asia and selection

The brown rat (Rattus norvegicus) is found wherever humans live and transmits many diseases, and its breeding produced the laboratory rat used widely in medical research. Here, we sequenced whole genomes from 118 rats to explore the origin and dispersal routes of the brown rat and the domestication of the laboratory rat. We showed that brown rats migrated about 3600 years ago from southern East Asia, rather than Northern Asia as formerly suggested, to the Middle East and then to Europe and Africa. Many genes involved in the immune system experienced positive selection in the wild brown rat, while genes involved in the nervous system and energy metabolism showed evidence of artificial selection during the domestication of laboratory strains. Our findings demystify the puzzling origin and migration of brown rats and reveal the impact of evolution and domestication on this animal.

evolutionary biology↗