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21.
De Schutter Kristof Verbeke Isabel Kontogiannatos Dimitriοs Dubruel Peter Swevers Luc Van Damme Els J. M. Smagghe Guy 《In vitro cellular & developmental biology. Plant》2022,58(4):511-520
In Vitro Cellular & Developmental Biology - Plant - While RNAi approaches based on transgenic plants overexpressing double-stranded RNAs (dsRNAs) have yielded a number of genetically modified... 相似文献
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Nico Dissmeyer Annika K. Weimer Stefan Pusch Kristof De Schutter Claire Lessa Alvim Kamei Moritz K. Nowack Bela Novak Gui-Lan Duan Yong-Guan Zhu Lieven De Veylder Arp Schnittger 《The Plant cell》2009,21(11):3641-3654
Entry into mitosis is universally controlled by cyclin-dependent kinases (CDKs). A key regulatory event in metazoans and fission yeast is CDK activation by the removal of inhibitory phosphate groups in the ATP binding pocket catalyzed by Cdc25 phosphatases. In contrast with other multicellular organisms, we show here that in the flowering plant Arabidopsis thaliana, cell cycle control does not depend on sudden changes in the phosphorylation pattern of the PSTAIRE-containing Cdk1 homolog CDKA;1. Consistently, we found that neither mutants in a previously identified CDC25 candidate gene nor plants in which it is overexpressed display cell cycle defects. Inhibitory phosphorylation of CDKs is also the key event in metazoans to arrest cell cycle progression upon DNA damage. However, we show here that the DNA damage checkpoint in Arabidopsis can also operate independently of the phosphorylation of CDKA;1. These observations reveal a surprising degree of divergence in the circuitry of highly conserved core cell cycle regulators in multicellular organisms. Based on biomathematical simulations, we propose a plant-specific model of how progression through the cell cycle could be wired in Arabidopsis. 相似文献
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During the past two decades, the use of probiotics as an alternative to the use of antibiotics has shown to be promising in
aquaculture, particularly in fish and shellfish larviculture. This article reviews the studies on probiotics in larviculture,
focusing on the current knowledge of their in vivo mechanisms of action. The article highlights that the in vivo mechanisms
of action largely remain to be unravelled. Several methodologies are suggested for further in vivo research, including studies
on gut microbiota composition, the use of gnotobiotic animals as test models, and the application of molecular techniques
to study host–microbe and microbe–microbe interactions. 相似文献
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Meelich K Zaleski CM Pecoraro VL 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1494):1271-9; discussion 1279-81
The molecular oxygen produced in photosynthesis is generated via water oxidation at a manganese-calcium cluster called the oxygen-evolving complex (OEC). While studies in biophysics, biochemistry, and structural and molecular biology are well known to provide deeper insight into the structure and workings of this system, it is often less appreciated that biomimetic modelling provides the foundation for interpreting photosynthetic reactions. The synthesis and characterization of small model complexes, which either mimic structural features of the OEC or are capable of providing insight into the mechanism of O2 evolution, have become a vital contributor to this scientific field. Our group has contributed to these findings in recent years through synthesis of model complexes, spectroscopic characterization of these systems and probing the reactivity in the context of water oxidation. In this article we describe how models have made significant contributions ranging from understanding the structure of the water-oxidation centre (e.g. contributions to defining a tetrameric Mn3Ca-cluster with a dangler Mn) to the ability to discriminate between different mechanistic proposals (e.g. showing that the Babcock scheme for water oxidation is unlikely). 相似文献
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Aminael Sánchez-Rodríguez Cindy Martens Kristof Engelen Yves Van de Peer Kathleen Marchal 《BMC evolutionary biology》2010,10(1):318
Background
Previous studies in Ascomycetes have shown that the function of gene families of which the size is considerably larger in extant pathogens than in non-pathogens could be related to pathogenicity traits. However, by only comparing gene inventories in extant species, no insights can be gained into the evolutionary process that gave rise to these larger family sizes in pathogens. Moreover, most studies which consider gene families in extant species only tend to explain observed differences in gene family sizes by gains rather than by losses, hereby largely underestimating the impact of gene loss during genome evolution. 相似文献28.
Gebruers K Brijs K Courtin CM Fierens K Goesaert H Rabijns A Raedschelders G Robben J Sansen S Sørensen JF Van Campenhout S Delcour JA 《Biochimica et biophysica acta》2004,1696(2):213-221
Two types of proteinaceous endoxylanase inhibitors occur in different cereals, i.e. the TAXI [Triticum aestivum endoxylanase inhibitor]-type and XIP [endoxylanase inhibiting protein]-type inhibitors. The present paper focuses on the TAXI-type proteins and deals with their structural characteristics and the identification, characterisation and heterologous expression of a TAXI gene from wheat. In addition, to shed light on the mechanism by which TAXI-type endoxylanase inhibitors work, the enzyme specificity, the optimal conditions for maximal inhibition activity, the molar complexation ratio and the inhibition kinetics of the inhibitors are explained and the effect of mutations of an endoxylanase on the inhibition by TAXIs is discussed. 相似文献
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Kristof Veitschegger Christian Kolb Eli Amson Marcelo R. Sánchez-Villagra 《Historical Biology》2019,31(4):510-516
AbstractLongevity and other life history variables are key to understanding evolutionary processes and the biology of extinct animals. For the past 20 years, the lifespan of cave bears received an increased interest. Studies focusing on incremental lines of tooth cementum resulted in detailed mortality patterns from different localities. In this review, we summarise literature on age estimation as well as mortality of different European cave bear localities and present novel data on longevity from 94 teeth originating from 20 European localities. Additionally, the relative tooth emergence pattern of the permanent dentition is investigated under the Schultz’s rule framework of possible life history implications. For this, the known sequences of extant bear species are compared with the one of cave bears. Our results suggest that the typical duration of the life of cave bears was 19 years but data from literature show that in rare cases ages of up to 30–32 years were achieved. Additionally, we present the oldest known age for the Middle Pleistocene cave bear Ursus deningeri, 29 years. The tooth eruption pattern of cave bears exhibits a heterochronic shift that implies, under the assumption of Schulz’ rule, a slightly faster life history than closely related species. 相似文献