Mitochondrial DNA in Siberian conifers indicates multiple postglacial colonization centers

Abstract

The geographic variation of the mitochondrial DNA in Siberian fir (Abies sibirica Ledeb.) was studied using the newly developed markers and compared with the phylogeographic pattern of another previously studied Siberian conifer, Siberian larch (Larix sibirica Ledeb.). Similar to Siberian larch, the distribution of mtDNA haplotypes in Siberian fir revealed clear differentiation among distinct geographic regions of southern Siberia and the Urals, likely indicating postglacial recolonization from several sources. The northern part of the range of both species was genetically homogeneous, which is probably due to its recent colonization from one of the glacial refugia. This conclusion is in agreement with published pollen and macrofossil data in Siberian fir and with the reconstruction of environmental niches indicating a dramatic reduction of the range and a likely survival of fir in certain southern areas during the Last Glacial Maximum (LGM), 21 thousand years ago. Although the modeling of the Siberian larch ecological niche reconstructed a shift of the range to the south at that period, the paleontological data indicated the presence of this species in most areas of the current range during LGM, which corresponds to the results of a previous historical demographic study suggesting that the population expansion preceding the LGM.

Sequence Capture of Mitochondrial Genome with PCR-Generated Baits Provides New Insights into the Biogeography of the Genus Abies Mill.

“…Samples of most species form monophyletic clades ( Figure 2 ), though variation was observed within the species that were represented in the analysis by more than one accession. Among the 4 A. sibirica sequences, including the reference, 16 mutations were encountered, 4 of which were previously detected during resequencing of A. sibirica mitochondrial contigs and were used in phylogeographic research [ 19 ]. In 3 A. alba Mill.…”

Mitochondrial DNA Confirms the American Origin of Modern Firs

“…To study the phylogeny of mtDNA of the genus Abies, we used resequencing of the assembly of the mitochondrial genome of Siberian fir A. sibirica, obtained on the basis of whole genome NGS sequencing [12]. For this, 42 fragments were randomly selected in the contigs of this assembly.…”

“…The fragments were 700-1500 bp in length. The PCR and sequencing conditions corresponded to those described in [12]. For further use, 27 pairs of primers were selected, which gave amplification in at least 13 Abies species out of 15.…”