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Biology subjects

Sammarco, I.

Publications and source records attributed to Sammarco, I..

3 recordsLinked to original sources

DNA methylation shows footprints of altitude selection in the clonal plant species Fragaria vesca

O_LIClimate change threatens plant species, potentially pushing them beyond their adaptive capacities. DNA methylation and other epigenetic modifications may enable rapid adaptation to environmental changes by generating locally adapted phenotypes. These phenotypic changes can be inherited across generations and may become targets of natural selection. However, direct evidence for selection on epialleles remains scarce. Addressing this gap is crucial, as population survival may heavily rely on DNA methylation, especially in clonal plants with limited genetic diversity. C_LIO_LIWe employed population genomics approaches to investigate altitude-driven selection on epigenetic sites in clonal offspring of natural woodland strawberry (Fragaria vesca) populations. These offspring were grown in a common garden and derived from seven populations spanning an altitudinal range. C_LIO_LIOur genomic, epigenomic, and transcriptomic analyses identified epialleles in clones exhibiting signs of selection related to altitude. These loci overlapped with genes involved in the O-methyltransferase activity, potentially aiding altitude adaptation through enhanced secondary metabolite production. Interestingly, these epialleles were mostly independent of genetic variation, suggesting they may have arisen stochastically or in response to environmental variation. C_LIO_LIThese findings suggest that heritable epigenetic variation could help clonal species quickly adapt to environmental challenges as those related to varying altitudes and/or temperatures. C_LI

evolutionary biology↗

Epigenetic variation in the Lombardy poplar along climatic gradients is independent of genetic structure and persists across clonal reproduction

- Environmental changes can trigger phenotypic variation in plants through epigenetic mechanisms, but strong genetic influences make it difficult to isolate and study epigenetic effects. Clonal trees with low genetic variation, such as the Lombardy poplar (Populus nigra cv. Italica Duroi), offer a unique system to study epigenetic variation associated with the environment. - We collected cuttings (ramets) of Lombardy poplar along a wide geographical range in Europe. We performed whole-genome-bisulfite sequencing of 164 ramets grown in a common garden and of a subset of 35 of the original parental individuals. Using historical bioclimatic data, we tested the relationship between DNA methylation and climatic gradients. - We found that average methylation levels in TEs and promoter regions correlate with biologically relevant climatic variables. Furthermore, we observed that DNA methylation was transmitted to the next clonal generation, but a fraction of the methylome changed relatively fast when comparing the parental individuals with the clonal offspring. - Our results suggest that the poplar methylome is a dynamic layer of information that can be transmitted to the clonal offspring and potentially affect how poplars acclimate to new environmental conditions.

ecology↗

Biodiversity lost: The phylogenetic relationships of a complete mitochondrial DNA genome sequenced from the extinct wolf population of Sicily

Using next-generation sequencing, we obtained for the first time a complete mitochondrial DNA genome from a museum specimen of the extinct wolf (Canis lupus) population of the island of Sicily (Italy). Phylogenetic analyses showed that this genome, which was aligned with a number of historical and extant complete wolf and dog mtDNAs sampled worldwide, was closely related to an Italian wolf mtDNA genome (TN93 and p-distances = 0.0012), five to seven times shorter than divergence among Sicilian and any other known wolf mtDNA genomes (distance range = 0.0050 - 0.0070). Sicilian and Italian haplotypes joined a basal clade belonging to the mtDNA haplogroup-2 of ancient western European wolf populations (Pilot et al. 2010). Bayesian calibration of divergence times indicated that this clade coalesced at MRCA = 13.400 years (with 95% HPD = 4000 - 21.230 years). These mtDNA findings suggest that wolves probably colonized Sicily from southern Italy towards the end of the last Pleistocene glacial maximum, when the Strait of Messina was almost totally dry. Additional mtDNA and genomic data will further clarify the origin and population dynamics before the extinction of wolves in Sicily.

zoology↗