Giant plant genomes are driven by the accumulation of repetitive DNA and its conversion into a „dark matter“
Genome size varies more than 2,000-fold between different plant species. This variation is not proportional to the number of genes but rather reflects differential accumulation of repetitive DNA. Our study revealed that giant plant genomes emerge due to less efficient removal of repetitive elements that subsequently diversify by acquiring random mutations. The resulting “dark matter” is no longer recognizable to molecular mechanisms facilitating repeat removal.
- Novak P., Guignard M.S., Neumann P., Kelly L.J., Mlinarec J., Koblizkova A., Dodsworth S., Kovarik A., Pellicer J., Wang W., Macas J., Leitch I.J., Leitch A.R. (2020) – Repeat-sequence turnover shifts fundamentally in species with large genomes. Nature Plants 6:1325-1329. [IF = 13.256]
Chronic exposure of soybean plants to nanomolar cadmium reveals specific additional high-affinity targets of Cd toxicity
Solving the global environmental and agricultural problem of chronic low-level cadmium (Cd) exposure (e.g. from traffic and fertiliser contamination) requires better mechanistic understanding. Our work revealed that chronic, sublethal cadmium toxicity in soybean plants impacts primary and secondary metabolism by hampering photosynthesis and affecting the micronutrient nutrition status, leading to changes in metabolite and lipid composition. It will help in risk assessment and breeding efforts.
- Andresen E., Lyubenova L., Hubáček T., Bokhari S.N.H., Matoušková Š., Mijovilovich A., Rohovec J., Küpper H. (2020) Chronic exposure of soybean plants to nanomolar cadmium reveals specific additional high-affinity targets of Cd toxicity. Journal of Experimental Botany 71, 1628-1644, DOI: https://doi.org/10.1093/jxb/erz530. [IF = 5.908]
Elimination of viroids from tobacco pollen involves a decrease in propagation rate and an increase of the degradation processes
We analyzed the mechanism of elimination of AFCVd and CBCVd viroids from pollen of infected and transformed N. tabacum at different stages. These viroids are eradicated from pollen during the last steps of its development. For the first time AGO5, DICER-like and TUDOR S-like nucleases were identified degrading viroids in concurrency with factors of ribosomal regulation IIIA and protein L5, whose modifications and viroid replication is according to model proposed blocked in pollen.
Matoušek J., Steinbachová L., Drábková L.Z., Kocábek T., Potěšil D., Mishra A.K., Honys D., Steger G.: Elimination of Viroids from Tobacco Pollen Involves a Decrease in Propagation Rate and an Increase of the Degradation Processes. Int J Mol Sci. 2020; 21(8):3029. DOI: 10.3390/ijms21083029. [IF = 4.556]
Intramolecular charge-transfer state of carotenoids siphonaxanthin and siphonein: function of non-conjugated acyl-oxy group
We used ultrafast transient absorption spectroscopy to study excited-state dynamics of two keto-carotenoids, siphonaxanthin and siphonein. These two carotenoids differ in the presence of dodecanoyl-oxy group in siphonein, which is attached to the C19 carbon on the same side of the molecule as the conjugated keto group. We show that this dodecanoyl-oxy group, though not in conjugation, is still capable of modifying excited state properties.
- Staleva-Musto H., Kuznetsova V., Bína D., Litvín R., Polívka T. (2020). Intramolecular charge‑transfer state of carotenoids siphonaxanthin and siphonein: function of non‑conjugated acyl‑oxy group. Photosynthesis Research 144: 127-135. DOI: 10.1007/s11120-019-00694-x [IF = 3.216]
Comparison of the incidence of viruses within germplasm, orchards and wild cherry trees in the Czech Republic
A total of 184 sweet and sour cherry trees in germplasm, orchards and wild trees were tested for 19 viruses using RT-PCR and sequencing. 10 viruses were detected, some of them for the first time. Virus frequency was different in locality types. No significant association were found between symptoms and virus presence. Next‐generation sequencing of selected samples yielded major genome portions (71.7–99.9%) of 9 viruses. The first complete coding sequences of a European PNRSV isolate was obtained.
- Přibylová J., Lenz O., Fránová J., Koloniuk I., & Špak J. (2020). Comparison of the incidence of viruses within germplasm, orchards and wild cherry trees in the Czech Republic. Annals of Applied Biology, 176(2), 138–146. http://doi.org/10.1111/aab.12577 [IF = 2.037]