Evolva (Denmark)

We investigated population genetics of the native tree species Acer velutinum Boiss., Fagus orientalis Lipsky, and Quercus castaneifolia C.A. Mey. in the Hyrcanian forests of northern Iran and also F. orientalis populations in the Euro-Siberian and Colchic subregions of northern Türkiye. We used the double-digest RADseq method and genotyped 90 populations and 1,589 individuals across the distribution range of the species. Genome-wide SNPs from 28 populations of A. velutinum, 32 populations of F. orientalis, and 30 Q. castaneifolia revealed higher genetic differentiation among A. velutinum populations than among F. orientalis and Q. castaneifolia. The global FST value was lowest for F. orientalis populations and highest for A. velutinum populations, while the global FIS value was negative for A. velutinum. Demographic history analysis revealed a bottleneck during the last glacial period (11,500—115,000 Kya) for the A. velutinum populations with reduced effective population size (Ne). All three species show multiple bottlenecks and reduced Ne during the Quaternary. Pronounced genetic divergence among A. velutinum populations in the Hyrcanian forests compared to the other two species suggests cryptic speciation. Conversely, F. orientalis and Q. castaneifolia populations showed low levels of genetic structure, suggesting that species-specific factors, such as pollen production and pollination efficiency, may have influenced the genetic patterns within these species in similar environments. The nucleotide diversity of F. orientalis populations in Iran is negatively correlated with altitude (p = 0.046). In contrast, A. velutinum populations show a significant correlation between nucleotide diversity and longitude (p = 0.008). Furthermore, the F. orientalis populations from Türkiye showed a distinct west–east genetic structure and were highly diverged from the Iranian F. orientalis populations.

Companion diagnostics (CDx) hail promise of improving the drug development process and precision medicine. However, there are various challenges involved in the clinical development and regulation of CDx, which are considered high-risk in vitro diagnostic medical devices given the role they play in therapeutic decision-making and the complications they may introduce with respect to their sensitivity and specificity. The European Union (E.U.) is currently in the process of bringing into effect in vitro Diagnostic Medical Devices Regulation (IVDR). The new Regulation is introducing a wide range of stringent requirements for scientific validity, analytical and clinical performance, as well as on post-market surveillance activities throughout the lifetime of in vitro diagnostics (IVD). Compliance with General Safety and Performance Requirements (GSPRs) adopts a risk-based approach, which is also the case for the new classification system. This changing regulatory framework has an impact on all stakeholders involved in the IVD Industry, including Authorized Representatives, Distributors, Importers, Notified Bodies, and Reference Laboratories and is expected to have a significant effect on the development of new CDx.

The development of medical applications exploiting the broad bioactivities of the diterpene therapeutic triptolide from Tripterygium wilfordii is limited by low extraction yields from the native plant. Furthermore, the extraordinarily high structural complexity prevents an economically attractive enantioselective total synthesis. An alternative production route of triptolide through engineered Saccharomyces cerevisiae (yeast) could provide a sustainable source of triptolide. A potential intermediate in the unknown biosynthetic route to triptolide is the diterpene dehydroabietic acid. Here, we report a biosynthetic route to dehydroabietic acid by transient expression of enzymes from T. wilfordii and Sitka spruce (Picea sitchensis) in Nicotiana benthamiana. The combination of diterpene synthases TwTPS9, TwTPS27, and cytochromes P450 PsCYP720B4 yielded dehydroabietic acid and a novel analog, tentatively identified as ‘miltiradienic acid’. This biosynthetic pathway was reassembled in a yeast strain engineered for increased yields of the pathway intermediates, the diterpene olefins miltiradiene and dehydroabietadiene. Introduction in that strain of PsCYP720B4 in combination with two alternative NADPH-dependent cytochrome P450 reductases resulted in scalable in vivo production of dehydroabietic acid and its analog from glucose. Approaching future elucidation of the remaining biosynthetic steps to triptolide, our findings may provide an independent platform for testing of additional recombinant candidate genes, and ultimately pave the way to biotechnological production of the high value diterpenoid therapeutic.

Rab5 is a small GTPase known to regulate vesicular trafficking during interphase. Here, we show that Rab5 also plays an unexpected role during mitotic progression. RNAi-mediated silencing of Rab5 caused defects in chromosome congression and extensive prometaphase delay, and it correlated with a severe reduction in the localization of the centromere-associated protein CENP-F to kinetochores. CENP-F is a component of the nuclear matrix required for chromosome congression that, at mitotic entry, localizes to the nuclear envelope and assembles on kinetochores, contributing to the establishment of kinetochore microtubule interactions. We found that Rab5 forms a complex with a subset of CENP-F in mitotic cells and regulates the kinetics of release of CENP-F from the nuclear envelope and its accumulation on kinetochores. Simultaneous depletion of both Rab5 and CENP-F recapitulated the mitotic defects caused by silencing of either Rab5 or CENP-F alone, indicating epistatic roles for these two proteins in the pathway that orchestrates chromosome congression. These results reveal the involvement of Rab5 in the proper execution of mitotic programs whose deregulation can undermine chromosomal stability.