Genome-wide analysis of genetic diversity and artificial selection in Large White pigs in Russia

Breeding practices adopted at different farms are aimed at maximizing the profitability of pig farming. In this work, we have analyzed the genetic diversity of Large White pigs in Russia. We compared genomes of historic and modern Large White Russian breeds using 271 pig samples. We have identified 120 candidate regions associated with the differentiation of modern and historic pigs and analyzed genomic differences between the modern farms. The identified genes were associated with height, fitness, conformation, reproductive performance, and meat quality

The Insights into Mitochondrial Genomes of Sunflowers

The significant difference in the mtDNA size and structure with simultaneous slow evolving genes makes the mitochondrial genome paradoxical among all three DNA carriers in the plant cell. Such features make mitochondrial genome investigations of particular interest. The genus Helianthus is a diverse taxonomic group, including at least two economically valuable species—common sunflower (H. annuus) and Jerusalem artichoke (H. tuberosus). The successful investigation of the sunflower nuclear genome provided insights into some genomics aspects and significantly intensified sunflower genetic studies. However, the investigations of organelles’ genetic information in Helianthus, especially devoted to mitochondrial genomics, are presented by limited studies. Using NGS sequencing, we assembled the complete mitochondrial genomes for H. occidentalis (281,175 bp) and H. tuberosus (281,287 bp) in the current investigation. Besides the master circle chromosome, in the case of H. tuberosus, the 1361 bp circular plasmid was identified. The mitochondrial gene content was found to be identical for both sunflower species, counting 32 protein-coding genes, 3 rRNA, 23 tRNA genes, and 18 ORFs. The comparative analysis between perennial sunflowers revealed common and polymorphic SSR and SNPs. Comparison of perennial sunflowers with H. annuus allowed us to establish similar rearrangements in mitogenomes, which have possibly been inherited from a common ancestor after the divergence of annual and perennial sunflower species. It is notable that H. occidentalis and H. tuberosus mitogenomes are much more similar to H. strumosus than H. grosseserratus

<i> </i>Mitochondrial genomes organization in alloplasmic lines of sunflower (<i>Helianthus annuus</i>) with various types of cytoplasmic male sterility

Background. Cytoplasmic male sterility (CMS) is a common phenotype in higher plants, which often is associated with rearrangements in mitochondrial DNA (mtDNA), and is widely used to produce hybrid seeds in a variety of valuable crop species. The CMS phenomenon investigations are also promote understanding of a fundamental issue of nuclear-cytoplasmic interactions in the ontogeny of higher plants. In the present study, we analyzed the structural changes in mitochondrial genomes of three alloplasmic lines of sunflower (Helianthus annuus). The investigation was focused on CMS line PET2, as there are very few reports about its mtDNA organization. Methods. The NGS sequencing, de novo assembly, and annotation of sunflower mitochondrial genomes were performed. The comparative analysis of mtDNA of HA89 fertile line and two HA89 CMS lines (PET1, PET2) occurred. Results. The mtDNA of the HA89 fertile line was almost identical to the HA412 line (NC_023337). The comparative analysis of HA89 fertile and CMS (PET1) analog mitochondrial genomes revealed 11852 bp inversion, 4732 bp insertion, 451 bp deletion and 18 variant sites. In mtDNA of HA89 (PET2) CMS line 77 kb translocation, 711 bp and 3780 bp deletions, as well as 1558 bp, 5050 bp, 14330 bp insertions were determined. There are also revealed 83 polymorphic sites sites in the PET2 mitochondrial genome, as compared with the fertile line Discussion. Among the revealed rearrangements the 1558 bp insertion resulted in new open reading frames formation - orf228 and orf246. The orf228 and orf246 could be the main reason for the development of PET2 CMS phenotype, whereas the role of other mtDNA reorganizations in CMS formation is negligible.</jats:p