Věda, výzkum, biologie

The relationship between transposable elements and ecological niches in the Greater Cape Floristic Region: A study on the genus Pteronia (Asteraceae)

Napsal uživatel vojta dne St, 10/12/2022 - 09:19

Non-coding repetitive DNA (repeatome) is an active part of the nuclear genome, involved in its structure, evolution and function. It is dominated by transposable elements (TEs) and satellite DNA and is prone to the most rapid changes over time. The TEs activity presumably causes the global genome reorganization and may play an adaptive or regulatory role in response to environmental challenges.

The importance of considering the evolutionary history of polyploids when assessing climatic niche evolution

Napsal uživatel vojta dne St, 10/12/2022 - 09:09

Although whole-genome duplication (WGD) is an important speciation force, we still lack a consensus on the role of niche differentiation in polyploid evolution. In addition, the role of genome doubling per se vs. later divergence on polyploid niche evolution remains obscure. One reason for this might be that the intraspecific genetic structure of polyploid complexes and interploidy gene flow is often neglected in ecological studies. Here, we aim to investigate to which extent these evolutionary processes impact our inference on niche differentiation of autopolyploids.

Target enrichment v rostlinné systematice aneb HybSeq kurz 2022

Napsal uživatel vojta dne Pá, 06/03/2022 - 11:42

Praktický kurz fylogenomických metod se zaměřením na NGS metodu Hyb-Seq. Metoda Hyb-Seq kombinuje cílené obohacení a tzv. mělké sekvenování genomu. V rámci kurzu budou probrány základy i nejnovějších poznatky v oblasti Hyb-Seq (návrh sond, laboratorní postup, analýza dat). Součástí kurzu je i práce s daty a jejich praktické analýzy různými přístupy, od primárních dat po konstrukci evolučních stromů koalescenčními a dalšími metodami. V laboratorní části kurzu budou připravovány a obohacovány NGS knihovny s využitím sonikátoru.

Taraxacum assemanii represents a new section: A revision of the misinterpreted Taraxacum primigenium, and the elucidation of the enigmatic Taraxacum section Primigenia (Compositae, Crepidinae)

Napsal uživatel vojta dne St, 09/29/2021 - 15:44

On the basis of new gatherings at the type locality, Taraxacum primigenium was evaluated taxonomically. Its achenes differ substantially from the protologue description that is based on achenes of T. assemanii. Taraxacum primigenium, also on the basis of an nrDNA analysis, is close to T. sect. Piesis, and represents a narrow endemic confined to the Lalezar Mts., SE Iran. Taraxacum assemanii, newly typified, is known from mountains of SE Anatolia and Lebanon, and from the Zagros in SW Iran.

Relative performance of customized and universal probe sets in target enrichment: A case study in subtribe Malinae

Napsal uživatel vojta dne Po, 07/26/2021 - 12:46

Custom probe design for target enrichment in phylogenetics is tedious and often hinders broader phylogenetic synthesis. The universal angiosperm probe set Angiosperms353 may be the solution. Here, we test the relative performance of Angiosperms353 on the Rosaceae subtribe Malinae in comparison with custom probes that we specifically designed for this clade. We then address the impact of bioinformatically altering the performance of Angiosperms353 by replacing the original probe sequences with orthologs extracted from the Malus domestica genome.

Taraxacum mirabile, an enigmatic sexual halophilous endemic dandelion, represents a new section

Napsal uživatel vojta dne Po, 03/15/2021 - 15:26

Taraxacum mirabile Wagenitz (Asteraceae, Cichorieae, Crepidinae), a remarkable but taxonomically unexplored endemic species of Central Anatolia, is examined in detail. It is shown to be a sexually reproducing diploid (2n=16) species. It used to be included in Taraxacum sect. Orientalia in the literature. However, the nrDNA analysis revealed that T. mirabile is remote from that section.

Parallel Alpine Differentiation in Arabidopsis arenosa

Napsal uživatel vojta dne Út, 12/29/2020 - 11:12

Parallel evolution provides powerful natural experiments for studying repeatability of evolution and genomic basis of adaptation. Well-documented examples from plants are, however, still rare, as are inquiries of mechanisms driving convergence in some traits while divergence in others. Arabidopsis arenosa, a predominantly foothill species with scattered morphologically distinct alpine occurrences is a promising candidate. Yet, the hypothesis of parallelism remained untested.

Low genetic differentiation despite high fragmentation in the endemic serpentinophyte Minuartia smejkalii (M. verna agg., Caryophyllaceae) revealed by RADSeq SNP markers

Napsal uživatel vojta dne Po, 01/13/2020 - 10:46

Minuartia smejkalii is an obligate serpentinophyte plant endemic to the Czech Republic. Since the 1960s, the species’ habitat has undergone strong human-mediated fragmentation, resulting in extinction of some populations and dramatic size reduction of the remaining populations. Thus, contrary to the typically stable serpentine habitats, M. smejkalii habitats underwent a recent and severe decline, which can exacerbate the effects of fragmentation on population genetic structure. We examined the genetic structure of all known M.

HybSeq course 2020

Napsal uživatel vojta dne Čt, 12/19/2019 - 21:25

Intensive 4-days (5th day is not compulsory, but is open for any discussion, if there would be interest) course to learn all theory about HybSeq and practically learn how to analyze HybSeq data, how to solve all problems, and how to evaluate differences among gene trees. Important part is enough time to discuss everything, including practical problems and projects of individual participants.