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801.
Matteo Schiavinato Alexandrina Bodrug-Schepers Juliane C. Dohm Heinz Himmelbauer 《The Plant journal : for cell and molecular biology》2021,106(3):672-688
Polyploidization is a well-known speciation and adaptation mechanism. Traces of former polyploidization events were discovered within many genomes, and especially in plants. Allopolyploidization by interspecific hybridization between two species is common. Among hybrid plants, many are domesticated species of agricultural interest and many of their genomes and of their presumptive parents have been sequenced. Hybrid genomes remain challenging to analyse because of the presence of multiple subgenomes. The genomes of hybrids often undergo rearrangement and degradation over time. Based on 10 hybrid plant genomes from six different genera, with hybridization dating from 10,000 to 5 million years ago, we assessed subgenome degradation, subgenomic intermixing and biased subgenome fractionation. The restructuring of hybrid genomes does not proceed proportionally with the age of the hybrid. The oldest hybrids in our data set display completely different fates: whereas the subgenomes of the tobacco plant Nicotiana benthamiana are in an advanced stage of degradation, the subgenomes of quinoa (Chenopodium quinoa) are exceptionally well conserved by structure and sequence. We observed statistically significant biased subgenome fractionation in seven out of 10 hybrids, which had different ages and subgenomic intermixing levels. Hence, we conclude that no correlation exists between biased fractionation and subgenome intermixing. Lastly, domestication may encourage or hinder subgenome intermixing, depending on the evolutionary context. In summary, comparative analysis of hybrid genomes and their presumptive parents allowed us to determine commonalities and differences between their evolutionary fates. In order to facilitate the future analysis of further hybrid genomes, we automated the analysis steps within manticore , which is publicly available at https://github.com/MatteoSchiavinato/manticore.git . 相似文献
802.
The different secretions of the mouth, the vestibular organs, and the vestibular pits of chaetognaths are shown on scanning
electron micrographs of the head ofSagitta setosa. The secreting organs are described and the functions of the secretions are discussed. In addition, the secretion under the
praeputium, a pit between the two rows of anterior teeth, and the surface structure of the teeth are described. 相似文献
803.
804.
Juliane Franze Andreas Ciroth 《The International Journal of Life Cycle Assessment》2011,16(4):366-379
Purpose
There is a need to assess social impacts of products along the full life cycle, not only to be able to address the “social dimension” in sustainability, but also for potentially improving the circumstances of affected stakeholders. This paper presents a case study for a social life cycle assessment (S-LCA) based on the recently published “Guidelines for Social Life Cycle Assessment of Products” developed by the United Nations Environment Programme/Society of Environmental Toxicology and Chemistry (UNEP/SETAC) working group. General aim is to “try out” the proposed method. The case study itself compares the impacts of rose production in Ecuador with the Netherlands. Furthermore, the objective is to identify differences and similarities in environmental and social life cycle modelling and both social and environmental hot spots in each of the life cycles. 相似文献805.
806.
807.
The architecture of the musculature of the eutardigrade species Milnesium tardigradum Doyère, 1840, Hypsibius sp. and Ramazzottius oberhaeuseri (Doyère in Ann Sci Nat Zool Sér 2(14):269–369, 1840) is investigated by phalloidin staining and confocal laser scanning microscopy. There are methodological problems in staining
eutardigrades due to physiological alterations under stress (anhydrobiosis) and due to penetration problems of the cuticle.
It is helpful to fix specimens in the state of asphyxy, where animals are stretched following an oxygen shortage in their
environment. The musculatures of all three species correspond in their general architecture, but differ in detail, such as
in the number of muscles. All muscles are isolated muscle strands. There are on each body side two dorsal and one ventral
muscle strands, in addition to a system of dorsoventral, lateral and lateroventral muscles. Seven median ventral attachment
points give rise to dorsoventral, ventrolateral and appendage muscles. The appendages receive several muscles originating
dorsally and ventrally. The number of muscles and the arrangement differ in each appendage. The fourth appendage shows the
greatest differences with a far smaller number of muscles compared to other species. The musculature shows comparably few
strict segmental patterns, for example, the musculature of each appendage differs from the other ones. By comparison with
literature data on the same species and data of Macrobiotus hufelandi it can be shown that eutardigrades have a roughly comparable muscular architecture, but that there are several differences
in detail.
Dedicated to Professor Westheide on the occasion of his 70th birthday. 相似文献
808.
809.
Johannes Raths Vid Švara Benedikt Lauper Qiuguo Fu Juliane Hollender 《Global Change Biology》2023,29(5):1390-1406
The acceleration of global climate change draws increasing attention towards interactive effects of temperature and organic contaminants. Many studies reported a higher sensitivity of aquatic invertebrates towards contaminant exposure with increasing or fluctuating temperatures. The hypothesis of this study was that the higher sensitivity of invertebrates is associated with the changes of toxicokinetic processes that determine internal concentrations of contaminants and consequently toxic effects. Therefore, the influence of temperature on toxicokinetic processes and the underlying mechanisms were studied in two key amphipod species (Gammarus pulex and Hyalella azteca). Bioconcentration experiments were carried out at four different temperatures with a mixture of 12 exposure relevant polar organic contaminants. Tissue and medium samples were taken in regular intervals and analysed by online solid-phase extraction liquid chromatography high-resolution tandem mass spectrometry. Subsequently, toxicokinetic rates were modelled and analysed in dependence of the exposure temperature using the Arrhenius equation. An exponential relationship between toxicokinetic rates versus temperature was observed and could be well depicted by applying the Arrhenius equation. Due to a similar Arrhenius temperature of uptake and elimination rates, the bioconcentration factors of the contaminants were generally constant across the temperature range. Furthermore, the Arrhenius temperature of the toxicokinetic rates and respiration was mostly similar. However, in some cases (citalopram, cyprodinil), the bioconcentration factor appeared to be temperature dependent, which could potentially be explained by the influence of temperature on active uptake mechanisms or biotransformation. The observed temperature effects on toxicokinetics may be particularly relevant in non-equilibrated systems, such as exposure peaks in summer as exemplified by the exposure modelling of a field measured pesticide peak where the internal concentrations increased by up to fourfold along the temperature gradient. The results provide novel insights into the mechanisms of chemical uptake, biotransformation and elimination in different climate scenarios and can improve environmental risk assessment. 相似文献
810.
Teixeira Fernanda Cardoso de Mattos Bruna da Silveira Mello Julia Eisenhardt de Cardoso Juliane Spohr Luiza Luduvico Karina Pereira Soares Mayara Sandrielly Pereira Carvalho Fabiano Barbosa Gutierres Jessie Martins Oliveira Campello Felix Anelize de Stefanello Francieli Moro Spanevello Roselia Maria 《Neurochemical research》2022,47(2):446-460
Neurochemical Research - This study investigated the effects of inosine on memory acquisition and consolidation, cholinesterases activities, redox status and Na+, K+-ATPase activity in a rat model... 相似文献