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Structure of a cereal purple acid phytase provides new insights to phytate degradation in plants

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Plant Communications 2022年第2期3卷 52-61页

作者： Raquel Faba-Rodriguez Yinghong Gu melissa Salmon Giuseppe Dionisio Henrik Brinch-pedersen Charles A.Brearley Andrew m.Hemmings School of Chemistry University of East AngliaNorwich Research ParkNorwich NR47TJUK School of Biological Sciences University of East AngliaNorwich Research ParkNorwich NR47TJUK Department of Agroecology Research Center FlakkebjergAarhus University4200 SlagelseDenmark College of Food Science and Technology Shanghai Ocean UniversityShanghai 201306China

Grain phytate,a mixed metal ion salt of inositol hexakisphosphate,accounts for 60%–80%of stored phosphorus in plants and is a potent antinutrient of non-ruminant animals including *** neofunctionalization of purple acid phytases(PAPhy),some cereals such as wheat and rye have acquired particularly high mature grain phytase *** PAPhy activity supplies phosphate,liberates metal ions necessary for seedling emergence,and obviates antinutrient effects of phytate,its manipulation and control are targeted crop *** we show the X-ray crystal structure of the b2 isoform of wheat PAPhy induced during *** high-resolution crystal structure suggests a model for phytate recognition that,validated by molecular dynamics simulations,implicates elements of two sequence inserts(termed PAPhy motifs)relative to a canonical metallophosphoesterase(mPE)domain in forming phytate-specific substrate specificity *** motifs are well conserved in PAPhys from monocot cereals,enzymes which are characterized by high specificity for *** by mutagenesis,residues His229 in PAPhy motif 4 and Lys410 in the mPE domain,both conserved in PAPhys,are found to strongly influence phytase *** results explain the observed phytase activity of cereal PAPhys and open the way to the rational engineering of phytase activity in planta.

关键词： wheat purple acid phytase X-ray crystallography stereospecificity

Geodynamic evolution of the Earth over the Phanerozoic:Plate tectonic activity and palaeoclimatic indicators

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Journal of Palaeogeography 2015年第2期4卷 167-188页

作者： christian Vérard Cyril Hochard Peter O.Baumgartner Gérard m.Stampfli Université de Lausanne (UNIL) Institut des Sciences de la Terre (ISTE)

During the last decades, numerous local reconstructions based on field geol- ogy were developed at the University of Lausanne （UNIL）. Team members of the UNIL partici- pated in the elaboration of a 600 ma to present global plate tectonic model deeply rooted in geological data, controlled by geometric and kinematic constraints and coherent with forces acting at plate boundaries. In this paper, we compare values derived from the tectonic model （ages of oceanic floor, production and subduction rates, tectonic activity） with a combination of chemical proxies （namely CO2, 87Sr/86Sr, glaciation evidence, and sea-level variations） known to be strongly in- fluenced by tectonics. One of the outstanding results is the observation of an overall decreas- ing trend in the evolution of the global tectonic activity, mean oceanic ages and plate velocities over the whole Phanerozoic. We speculate that the decreasing trend reflects the global cooling of the Earth system. Additionally, the parallel between the tectonic activity and CO2 together with the extension of glaciations confirms the generally accepted idea of a primary control of CO2 on climate and highlights the link between plate tectonics and CO2 in a time scale greater than 107 yr. Last, the wide variations observed in the reconstructed sea-floor production rates are in contradiction with the steady-state model hypothesized by some.

关键词： geodynamic plate tectonics plate model Phanerozoic palaeoclimate CO2,strontium glaciation

3D palaeogeographic reconstructions of the Phanerozoic versus sea-level and Sr-ratio variations

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Journal of Palaeogeography 2015年第1期4卷 64-84页

作者： christian Vérard Cyril Hochard Peter O.Baumgartner Gérard m.Stampfli Université de Lausanne (UNIL) Institut des Sciences de la Terre (ISTE)Geopolis Ch–1015 Lausanne Switzerland

A full global geodynamical model over 600 million years （ma） has been de- veloped at the University of Lausanne during the past 20 years. We show herein how the 2D maps were converted into 3D （i.e., full hypsometry and bathymetry）, using a heuristic-based approach. Although the synthetic topography may be viewed as relatively crude, it has the advantage of being applicable anywhere on the globe and at any geological time. The model allows estimating the sea-level changes throughout the Phanerozoic, with the possibility, for the first time, to flood accordingly continental areas. One of the most striking results is the good correlation with ＂measured＂ sea-level changes, implying that long-term variations are predominantly tectonically-driven. Volumes of mountain relief are also estimated through time and compared with strontium isotopic ratio （Sr-ratio）, commonly thought to reflect mountain belt erosion. The tectonic impact upon the general Sr-retio trend is shown herein for the first time, although such influence was long been inferred.

关键词： palaeogeography reconstruction hypsometry bathymetry sea-level Sr-ratio tectonic-climate relationship

The beginning of a new era:pioneering direct screens for RNA modulators

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2660-2661页

作者： F.X.Reymond Sutandy Rebecca George Tharyan christian münch Institute of Biochemistry II Goethe University FrankfurtFaculty of MedicineFrankfurt am MainGermany Frankfurt Cancer Institute Frankfurt am MainGermany CardioPulmonary Institute Frankfurt am MainGermany

In a recent study published in Nature,1 Aguilar et *** the small molecule X1 that targets the long non-coding RNA *** X1 binding,Xist changes its structure,which prevents its role in X-chromosome inactivation(XCI).The vast majority of small molecule screens in drug discovery focus on targeting proteins.2,3 However,protein coding sequences merely constitute~1.5%of the human genome and only a small fraction of these proteins are currently targetable.2 In contrast,90%of the human genome is transcribed into RNA in different forms,which makes RNAs compelling targets for small molecule drugs.3 modulating mRNAs with small molecules could be an alternative route to change the levels of the corresponding protein products and their activities,especially for currently undruggable *** the diverse functions carried out by different classes of RNAs in cells,altering RNAs would provide a broad range of potential drug targets in the human *** modulating RNAs with small molecules carries a number of advantages,identifying RNA-targeting small molecules has proven difficult;previous compounds had been identified indirectly by phenotypic screens.1–3 Systematic approaches to screen for RNAtargeting compounds had been lacking.

关键词： drugs screen currently

Perception of the muller-Lyer illusion in guppies

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Current Zoology 2020年第2期66卷 205-213页

作者： maria SANTACA christian AGRILLO Department of General Psychology University of PadovaVia Venezia 8Padova 35131Italy

The muller-Lyer illusion is a well-known distortion illusion that occurs when the spatial arrangement of inducers(i.e.,inwards-or outwards-pointing arrowheads)influences a line's perceived relative *** date,this illusion has been reported in several animal species but only in 1 teleost fish(i.e.,redtail splitfins Xenotoca eiseni),although teleost fish represent approximately 50%of vertebrate *** investigated the perception of this illusion in another teleost fish:guppies Poecilia reticulata,a species that diverged from the redtail splitfin 65 million years *** guppies were trained to select the longer between 2 lines;after meeting the learning criterion,illusory trials were *** trials were also arranged to exclude the possibility that their choices were based on potential spatial biases that relate to the illusory *** guppies'overall performance indicated that they were susceptible to the muller-Lyer illusion,perceiving the line with the inwards-pointing arrowheads as *** performance in the control trials excluded the possibility that the subjects used the physical differences between the 2 figures as the discriminative cue in the illusory *** study suggests that sensibility to the muller-Lyer illusion could be widespread across teleost fish and reinforces the idea that the perceptual mechanisms underlying size estimation might be similar across vertebrates.

关键词： comparative perception muller-Lyer illusion Poecilia reticulata visual illusions

Recent advancements in the analysis of bone microstructure: new dimensions in forensic anthropology

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Forensic Sciences Research 2018年第4期3卷 294-309页

作者： Janna m.Andronowski christian Crowder miriam Soto martinez Department of Biology The University of AkronAkronOHUSA Harris County Institute of Forensic Sciences HoustonTXUSA

Bone is a mechanically active,three-dimensionally(3D)complex,and dynamic tissue that changes in structure over the human *** tissue exists and remodels in 3D and changes over time,introducing a fourth *** products of the remodelling process,secondary and fragmentary osteons,have been studied substantially using traditional two-dimensional(2D)*** a result,much has been learned regarding the biological information encrypted in the histomorphology of bone,yielding a wealth of information relating to skeletal structure and ***-dimensional imaging modalities,however,hold the potential to provide a much more comprehensive understanding of bone *** visualization and analysis of bone using high-resolution 3D imaging will improve current understandings of bone biology and have numerous applications in both biological anthropology and *** recent technological advancements,we can hone current anthropological applications of the analysis of bone microstructure and accelerate research into the third and fourth dimensional *** review will explore the methodological approaches used historically by anthropologists to assess cortical bone microstructure,spanning from histology to current ex vivo imaging modalities,discuss the growing capabilities of in vivo imaging,and conclude with an introduction of novel nonhistological modalities for investigating bone quality.

关键词： Forensic science forensic anthropology cortical bone synchrotron micro-CT in vivo ex vivo histological age estimation bone quality

Validation of a novel animal model for sciatic nerve repair with an adipose-derived stem cell loaded fibrin conduit

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Neural Regeneration Research 2018年第5期13卷 854-861页

作者： maximilian m.Saller Rosa-Eva Huettl Julius m.mayer Annette Feuchtinger christian Krug Thomas Holzbach Elias Volkmer Experimental Surgery and Regenerative medicine (Experimed) Department of General Trauma and Reconstructive SurgeryLudwig-Maximilians-University (LMU) max-Planck-Institute of Psychiatry Department of Stress Neurobiology and Neurogenetics Department of Hand- Plastic-and Aesthetic Surgery Ludwig-Maximilians-University (LMU) Research Unit Analytical Pathology Munich Helmholtz Zentrum Muenchen-German Research Center for Environmental Health (GmbH) Department of Hand and Plastic Surgery Spital Thurgau AG

Despite the regenerative capabilities of peripheral nerves, severe injuries or neuronal trauma of critical size impose immense hurdles for proper restoration of neuro-muscular circuitry. Autologous nerve grafts improve re-establishment of connectivity, but also comprise substantial donor site morbidity. We developed a rat model which allows the testing of different cell applications, i.e., mesenchymal stem cells, to improve nerve regeneration in vivo. To mimic inaccurate alignment of autologous nerve grafts with the injured nerve, a 20 mm portion of the sciatic nerve was excised, and sutured back in place in reversed direction. To validate the feasibility of our novel model, a fibrin gel conduit containing autologous undifferentiated adipose-derived stem cells was applied around the coaptation sites and compared to autologous nerve grafts. After evaluating sciatic nerve function for 16 weeks postoperatively, animals were sacrificed, and gastrocnemius muscle weight was determined along with morphological parameters（g-ratio, axon density ＆ diameter） of regenerating axons. Interestingly, the addition of undifferentiated adipose-derived stem cells resulted in a significantly improved re-myelination, axon ingrowth and functional outcome, when compared to animals without a cell seeded conduit. The presented model thus displays several intriguing features： it imitates a certain mismatch in size, distribution and orientation of axons within the nerve coaptation site. The fibrin conduit itself allows for an easy application of cells and, as a true critical-size defect model, any observed improvement relates directly to the performed intervention. Since fibrin and adipose-derived stem cells have been approved for human applications, the technique can theoretically be performed on humans. Thus, we suggest that the model is a powerful tool to investigate cell mediated assistance of peripheral nerve regeneration.

关键词： critical-size nerve defect fibrin conduit autologous nerve transplant peripheral nerve regeneration adipose-derived stem/progenitor cells sciatic function index sciatic nerve re-innervation axon guidance peripheral circuitry

Inflammatory pathways of importance for management of inflammatory bowel disease

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World Journal of Gastroenterology 2014年第1期20卷 64-77页

作者： Jannie pedersen mehmet Coskun Christoffer Soendergaard mohammad Salem Ole Haagen Nielsen Department of Gastroenterology Medical SectionUniversity of CopenhagenHerlev HospitalDK-2730 HerlevDenmark Department of Cellular and molecular medicine the Panum InstituteUniversity of CopenhagenDK-2200 CopenhagenDenmark

Inflammatory bowel disease (IBD) is a group of chronic disorders of the gastrointestinal tract comprising Crohn’s disease (CD) and ulcerative colitis (UC). Their etiologies are unknown, but they are characterised by an imbalanced production of pro-inflammatory mediators, e.g., tumor necrosis factor (TNF)-α, as well as increased recruitment of leukocytes to the site of inflammation. Advantages in understanding the role of the inflammatory pathways in IBD and an inadequate response to conventional therapy in a large portion of patients, has over the last two decades lead to new therapies which includes the TNF inhibitors (TNFi), designed to target and neutralise the effect of TNF-α. TNFi have shown to be efficient in treating moderate to severe CD and UC. However, convenient alternative therapeutics targeting other immune pathways are needed for patients with IBD refractory to conventional therapy including TNFi. Indeed, several therapeutics are currently under development, and have shown success in clinical trials. These include antibodies targeting and neutralising interleukin-12/23, small pharmacologic Janus kinase inhibitors designed to block intracellular signaling of several pro-inflammatory cytokines, antibodies targeting integrins, and small anti-adhesion molecules that block adhesion between leukocytes and the intestinal vascular endothelium, reducing their infiltration into the inflamed mucosa. In this review we have elucidated the major signaling pathways of clinical importance for IBD therapy and highlighted the new promising therapies available. As stated in this paper several new treatment options are under development for the treatment of CD and UC, however, no drug fits all patients. Hence, optimisations of treatment regimens are warranted for the benefit of the patients either through biomarker establishment or other rationales to maximise the effect of the broad range of mode-of-actions of the present and future drugs in IBD.

关键词： Anti-tumor necrosis factor, Biologics, Crohn’ s disease, Pro-inflammatory cytokines, Signaling pathways, Treatment, Ulcerative colitis

Effects of supplementation of green tea extract on the milk performance of peripartal dairy cows and the expression of stress response genes in the liver

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Journal of Animal Science and Biotechnology 2020年第4期11卷 1163-1174页

作者： Denise K.Gessner Corinna Brock Lena m.Hof Erika most christian Koch Klaus Eder Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenHeinrich-Buff-Ring 26-3235392 GiessenGermany Educational and Research Centre for Animal Husbandry Hofgut Neumühle67728 Münchweiler an der AlsenzGermany.

Background: We hypothesised that supplementation of green tea extract(GTE) in dairy cows during the transition period can attenuate proinflammatory conditions and prevent endoplasmic reticulum(ER) stress in the liver of these cows. Thirty Holstein cows with an average parity of 3.06(± 1.31, SD) were divided into a control group and a group that received a daily amount of 10 g of GTE from d 7 before the calving day and a daily amount of 20 g of GTE from the day of calving until d 7 of ***: Cows supplemented with GTE did not show differences in energy intake or milk yield in weeks 2–7 of lactation. However, these cows had a lower milk fat concentration and a lower energy corrected milk yield than the control cows and showed a trend of improved energy balance. The relative m RNA concentrations of proinflammatory genes, genes involved in the acute phase reaction and antioxidant genes in the liver in weeks 1, 4 and 7 of lactation were not different between the two groups of cows. The concentrations of α-tocopherol and the Trolox equivalent antioxidant capacity in plasma were not different between the two groups. However, the group supplemented with GTE showed significant reductions of some genes of the unfolded protein response(UPR) in week 1 and a trend of lower liver triacylglycerol(TAG) concentrations in the liver compared to the control ***: This study shows that supplementation of GTE in dairy cows lowers the fat concentration in the milk but overall has no effect on the expression of inflammatory genes and the antioxidative status in dairy cows during early lactation. The finding of reduced m RNA levels of genes involved in the UPR at week 1, however, supports other results showing that supplementation of polyphenols could prevent the development of ER stress in the liver of cows during early lactation. The finding of a tendency towards a reduced TAG concentration in the liver of cows supplemented with GTE might be due to an improved ene

关键词： Animal nutrition Cow Green tea extract Liver metabolism milk performance