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Bogdanov, V. P.

Publications and source records attributed to Bogdanov, V. P..

3 recordsLinked to original sources

Sanger validation of WGS variants - when to?

With the development of Next-Generation Sequencing (NGS) technologies it became possible to simultaneously analyze millions of variants. Despite the quality improvement it is generally still required to confirm the variants before reporting. However, in recent years the dominant idea is that one could define the quality thresholds for "high quality" variants which do not require orthogonal validation. Despite that, no works to date report the concordance between variants from whole genome sequencing and their gold-standard Sanger validation. In this study we analyzed the concordance for 1756 WGS variants in order to establish the appropriate thresholds for high-quality variants filtering. Resulting thresholds allowed us to drastically reduce the number of variants which require validation, to 5,6% and 1.2% of the initial set for caller-agnostic thresholds and caller-dependent QUAL threshold respectively.

genomics↗

Knockout of cyclin dependent kinases 8 and 19 leads to depletion of cyclin C and suppresses spermatogenesis and male fertility in mice

Paralogs CDK8 and CDK19 are regulatory kinases associated with the transcriptional Mediator complex. We have e generated mice with the systemic inducible Cdk8 knockout on the background of Cdk19 constitutive knockout. Cdk8/19 double knockout (iDKO) males, but not single Cdk8 and Cdk19 KO, had an atrophic reproductive system and were infertile. The iDKO males lacked postmeiotic spermatids and spermatocytes after meiosis I pachytene. Testosterone levels were decreased whereas the amounts of the luteinizing hormone were unchanged. Single cell RNA sequencing showed marked differences in the expression of steroidogenic genes (such as Cyp17a1, Star and Fads) in Leydig cells concomitant with alterations in Sertoli cells and spermatocytes likely associated with impaired synthesis of steroids. Star and Fads were also downregulated in cultivated Leydig cells after iDKO. The treatment of primary Leydig cells culture with a CDK8/19 inhibitor did not induce the same changes in gene expression as iDKO, and prolonged treatment of mice with a CDK8/19 inhibitor did not affect the size of testes. iDKO, in contrast to single knockouts or treatment with a CDK8/19 kinase inhibitor, led to depletion of cyclin C (CcnC), the binding partner of CDK8/19 that has been implicated in CDK8/19-independent functions. This suggests that the observed phenotype was likely mediated through kinase-independent activities of CDK8/19, such as CcnC stabilization.

developmental biology↗

The genome of the toxic invasive species Heracleum sosnowskyi carries an increased number of genes despite the absence of recent whole-genome duplications

Heracleum sosnowskyi, belonging to a group of giant hogweeds, is a plant with large effects on ecosystems and human health. It is an invasive species that contributes to the deterioration of grassland ecosystems. The ability of H. sosnowskyi to produce linear furanocoumarins (FCs), photosensitizing compounds, makes it very dangerous. At the same time, linear FCs are compounds with high pharmaceutical value that are used in skin disease therapies. Despite this high importance, it has not been the focus of genetic and genomic studies. Here, we report a chromosome-scale assembly of the Sosnowskys hogweed genome. Genomic analysis revealed an unusually high number of genes (55 206) in the hogweed genome, in contrast to the 25-35 thousand found in most plants. However, we did not find any traces of recent whole genome duplications not shared with its confamiliar, Daucus carota (carrot), which has approximately thirty thousand genes. The analysis of the genomic proximity of duplicated genes indicates tandem duplications as a main reason for this increase. We performed a genome-wide search of the genes of the FC biosynthesis pathway and their expression in aboveground plant parts. Using a combination of expression data and phylogenetic analysis, we found candidate genes for psoralen synthase and experimentally showed the activity of one of them using a heterologous yeast expression system. These findings expand our knowledge on the evolution of gene space in plants and lay a foundation for further analysis of hogweed as an invasive plant and as a source of FCs.

genomics↗