Large-scale mitogenome sequencing reveals consecutive expansions of domestic taurine cattle and supports sporadic aurochs introgression.

The contribution of domestic cattle in human societies is enormous, making cattle, along with other essential benefits, the economically most important domestic animal in the world today. To expand existing knowledge on cattle domestication and mitogenome diversity, we performed a comprehensive complete mitogenome analysis of the species (802 sequences, 114 breeds). A large sample was collected in South-east Europe, an important agricultural gateway to Europe during Neolithization and a region rich in cattle biodiversity. We found 1725 polymorphic sites (810 singletons, 853 parsimony-informative sites and 57 indels), 701 unique haplotypes, a haplotype diversity of 0.9995 and a nucleotide diversity of 0.0015. In addition to the dominant T3 and several rare haplogroups (Q, T5, T4, T2 and T1), we have identified maternal line in Austrian Murbodner cattle that possess surviving aurochs' mitochondria haplotype P1 that diverged prior to the Neolithization process. This is convincing evidence for rare female-mediated adaptive introgression of wild aurochs into domesticated cattle in Europe. We revalidated the existing haplogroup classification and provided Bayesian phylogenetic inference with a more precise estimated divergence time than previously available. Occasionally, classification based on partial mitogenomes was not reliable; for example, some individuals with haplogroups P and T5 were not recognized based on D-loop information. Bayesian skyline plot estimates (median) show that the earliest population growth began before domestication in cattle with haplogroup T2, followed by Q (~10.0-9.5 kyBP), whereas cattle with T3 (~7.5 kyBP) and T1 (~3.0-2.5 kyBP) expanded later. Overall, our results support the existence of interactions between aurochs and cattle during domestication and dispersal of cattle in the past, contribute to the conservation of maternal cattle diversity and enable functional analyses of the surviving aurochs P1 mitogenome.

Enzymatic and mRNA transcript response of ovine 6-phosphogluconate dehydrogenase (6PGD) in respect to different weights from weaning to four months of age.

Ovine 6-phosphogluconate dehydrogenase (6PGD), an enzyme of the pentose phosphate pathway, provides the necessary compounds of NADPH for the synthesis of fatty acids. Much of research has been conducted not only on the enzymatic level, but also on molecular level elucidating its cDNA sequence. Herein, we tried to elucidate if any correlation between enzymatic activity and expression of ovine 6PGD gene exists, in respect to two different weights from weaning to 4 months old. 18 male and 16 female lambs of Chios breed were randomly selected after weaning and assigned to two groups based on sex in a different experimental open-plan shed. Two subgroups were defined in each sex and they were slaughtered at 25 kg and 30 kg, respectively. Samples of adipose tissue (tail, perirenal and shoulder site) were collected and 6PGD enzymatic activity, gene expression, and characteristics of adipocytes were determined. According to the determined data, tail subcutaneous adipose tissue matures later than the others examined tissues and has a diminished lipogenic activity. A 6PGD gene expression pattern was not followed by analogous changes of its enzymatic activity, suggesting that other mechanisms such as post transcription or/and post translation regulation may be involved.

Enzymatic and mRNA Transcript Response of Ovine 6-Phosphogluconate Dehydrogenase (6PGD) in Respect to Different Milk Yield.

Ovine 6-phosphogluconate dehydrogenase (6PGD) is an enzyme of the pentose phosphate pathway, providing the necessary compounds of NADPH for the synthesis of fatty acids. Much of research has been conducted both on enzymatic level and on molecular level. However, to our knowledge, any correlation between enzymatic activity and 6PGD gene expression pattern related to different physiological stages has not been yet reported. With this report, we tried to highlight if any correlation between enzymatic activity and expression of ovine 6PGD gene exists, in respect to different milk yield. According to the determined enzymatic activities and adipocytes characteristics, ewes with low milk production possessed a greater (P ≤ .001) 6PGD activity and larger adipocytes than the highly productive ewes. Although 6PGD expression pattern was higher in low milk yield ewes than in ewes with high milk production, this difference was not found statistically significant. Thus, 6PGD gene expression pattern was not followed by so rapid and great/sizeable changes as it was observed for its respective enzymatic activity, suggesting that other mechanisms such as post translation regulation may be involved in the regulation of the respective gene.