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11.
Abstract An investigation has been carried out on the effects of some macroelements on the growth and differentiation of carnation meristem-tip. The meristem-tips were cultured over one year period using BAKER and PHILLIPS (1962) modified medium as basal medium. Different concentration of N, P, K and S were used and their effect on the explants was scored. Variation in the K level had no effect on the growth of the meristems except in one case while P at 1/2 X, 1/4 X to 1/8 X levels considerably increased the number of plantlets obtained. N supplied as urea had an inhibiting action on the explant as two different sources of S did. 相似文献
12.
Ferlosio Amedeo Doldo Elena Agostinelli Sara Costanza Gaetana Centofanti Federica Sidoni Angelo Orlandi Augusto 《Molecular biology reports》2020,47(9):6879-6886
Molecular Biology Reports - In recent years, new treatments with novel action mechanisms have been explored for advanced non-small cell lung cancer (NSCLC). Retinoids promote cancer cell... 相似文献
13.
A PBX1 transcriptional network controls dopaminergic neuron development and is impaired in Parkinson's disease
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J Carlos Villaescusa Bingsi Li Enrique M Toledo Pia Rivetti di Val Cervo Shanzheng Yang Simon RW Stott Karol Kaiser Saiful Islam Daniel Gyllborg Rocio Laguna‐Goya Michael Landreh Peter Lönnerberg Anna Falk Tomas Bergman Roger A Barker Sten Linnarsson Licia Selleri Ernest Arenas 《The EMBO journal》2016,35(18):1963-1978
14.
Chiara Salvesi Stefania Silvi Dennis Fiorini Serena Scortichini Gianni Sagratini Francesco A. Palermo Renato De Leone Nadaniela Egidi Lorella Fatone Carlo Cifani Amedeo Amedei Francesca Scocchera Mara Morici Beatrice Gatto Fausto Mannucci Valerio Valeriani Marco Malavasi Sara Servili Andrea Casula Andrea Cresci Ivano Corradetti Francesco Carpi Matteo Picciolini Maria Magdalena Coman Maria Cristina Verdenelli 《Journal of applied microbiology》2022,133(5):2941-2953
15.
Johannes Schilling Christian Jost Ioana Mariuca Ilie Joachim Schnabl Oralea Buechi Rohan S. Eapen Rafaela Truffer Amedeo Caflisch Patrik Forrer 《The Journal of biological chemistry》2022,298(1)
Designed ankyrin repeat proteins (DARPins) are antibody mimetics with high and mostly unexplored potential in drug development. By using in silico analysis and a rationally guided Ala scanning, we identified position 17 of the N-terminal capping repeat to play a key role in overall protein thermostability. The melting temperature of a DARPin domain with a single full-consensus internal repeat was increased by 8 °C to 10 °C when Asp17 was replaced by Leu, Val, Ile, Met, Ala, or Thr. We then transferred the Asp17Leu mutation to various backgrounds, including clinically validated DARPin domains, such as the vascular endothelial growth factor-binding domain of the DARPin abicipar pegol. In all cases, these proteins showed improvements in the thermostability on the order of 8 °C to 16 °C, suggesting the replacement of Asp17 could be generically applicable to this drug class. Molecular dynamics simulations showed that the Asp17Leu mutation reduces electrostatic repulsion and improves van-der-Waals packing, rendering the DARPin domain less flexible and more stable. Interestingly, this beneficial Asp17Leu mutation is present in the N-terminal caps of three of the five DARPin domains of ensovibep, a SARS-CoV-2 entry inhibitor currently in clinical development, indicating this mutation could be partly responsible for the very high melting temperature (>90 °C) of this promising anti-COVID-19 drug. Overall, such N-terminal capping repeats with increased thermostability seem to be beneficial for the development of innovative drugs based on DARPins. 相似文献
16.
PHYLOGENETIC RELATIONSHIPS AMONG PAPER WASP SOCIAL PARASITES AND THEIR HOSTS (HYMENOPTERA: VESPIDAE; POLISTINAE) 总被引:1,自引:0,他引:1
James M. Carpenter Joan E. Strassmann Stefano Turillazzi Colin R. Hughes Carlos R. Solís Rita Cervo 《Cladistics : the international journal of the Willi Hennig Society》1993,9(2):129-146
Abstract— Cladistic analyses of data from allozyme polymorphisms in paper wasp social parasites and their hosts do not support the hypothesis that social parasites are most closely related to their hosts. Electrophoretic data are adduced for nine species of Polistes , including all three known species of social parasites ( Sulcopolistes ) and their hosts. Three different coding methods are investigated; in no case do the social parasites cluster most closely with their hosts. Rather, there is limited evidence that they form a monophyletic group. However, formal taxonomic recognition of Sulcopolistes is not justified, as it renders Polistes sensu stricto paraphyletic. Although the social parasites are not most closely related to their hosts, hosts and parasites belong in the same subgenus and share many characteristics that may have facilitated the exploitation and deception practised by the parasites on the hosts. 相似文献
17.
To verify whether the sleep-inducing properties of oleamide were related to its ability to perturb membrane homeoviscosity, affecting 5-HT(2A) receptors, we compared the effects of oleamide and oleic acid, the latter lacking both the sleep-inducing effect and the action on 5-HT(2A) receptors. In binding studies the two compounds did not directly interact with rat brain cortex 5-HT(2A) receptors, nor did they increase the affinity of a 5-HT(2A) agonist, either in vitro or ex vivo. They had similar fluidizing effects, in vitro at high concentrations (>/=10 microM), and ex vivo after a dose of 100 mg/kg, and they reduced locomotor activity with similar potency. There thus appears to be no causal relationship between the fluidizing effects of oleamide and its sleep-inducing properties. 相似文献
18.
The N-terminal domain of the Tn916 integrase protein (INT-DBD) is responsible for DNA binding in the process of strand cleavage and joining reactions required for transposition of the Tn916 conjugative transposon. Site-specific association is facilitated by numerous protein-DNA contacts from the face of a three-stranded beta-sheet inserted into the major groove. The protein undergoes a subtle conformational transition and is slightly unfolded in the protein-DNA complex. The conformation of many charged residues is poorly defined by NMR data but mutational studies have indicated that removal of polar side chains decreases binding affinity, while non-polar contacts are malleable. Based on analysis of the binding enthalpy and binding heat capacity, we have reasoned that dehydration of the protein-DNA interface is incomplete. This study presents results from a molecular dynamics investigation of the INT-DBD-DNA complex aimed at a more detailed understanding of the role of conformational dynamics and hydration in site-specific binding. Comparison of simulations (total of 13 ns) of the free protein and of the bound protein conformation (in isolation or DNA-bound) reveals intrinsic flexibility in certain parts of the molecule. Conformational adaptation linked to partial unfolding appears to be induced by protein-DNA contacts. The protein-DNA hydrogen-bonding network is highly dynamic. The simulation identifies protein-DNA interactions that are poorly resolved or only surmised from the NMR ensemble. Single water molecules and water clusters dynamically optimize the complementarity of polar interactions at the 'wet' protein-DNA interface. The simulation results are useful to establish a qualitative link between experimental data on individual residue's contribution to binding affinity and thermodynamic properties of INT-DBD alone and in complex with DNA. 相似文献
19.
Ischemic preconditioning changes the pattern of coronary reactive hyperemia regardless of mitochondrial ATP-sensitive K(+) channel blockade 总被引:1,自引:0,他引:1
Pagliaro P Chiribiri A Rastaldo R Mancardi D Penna C Gattullo D Losano G 《Life sciences》2002,71(19):2299-2309
Ischemic preconditioning increases the velocity of vasodilatation and reduces the total hyperemic flow (THF) of a subsequent coronary reactive hyperemia (CRH). The increase in the velocity of vasodilatation has been shown to depend on an up-regulation of the endothelial release of nitric oxide, while the reduction of THF is attributed to an adenosine A(1) receptor-mediated mechanism. We investigated whether the changes in CRH induced by preconditioning ischemia (PI) can still be obtained after blockade of mitochondrial ATP-sensitive K(+) channels by sodium 5-hydroxydecanoate (5-HD), and whether the blockade per se affects the pattern of CRH.In anesthetized goats, flow was recorded from the left circumflex coronary artery (LCCA). CRH was obtained with the occlusion of LCCA for 15 s. PI was obtained by 2 cycles of 2.5 min of LCCA occlusion with a 5 min interval of reperfusion between the two occlusions. CRH was studied before and after i.v. administration of 5-HD (20 mg/kg), as well as in the presence of 5-HD after PI. Following 5-HD, the pattern of CRH remained unchanged. After 5-HD and PI, velocity of vasodilatation and total hyperemic flow of CRH showed the same changes as in previous studies after PI alone. It was concluded that the blockade of mitochondrial ATP-sensitive K(+) channels, which is reported to prevent myocardial protection, does not affect CRH and does not prevent PI from increasing the velocity of vasodilatation and reducing THF. These results demonstrate that the changes induced in CRH by preconditioning are independent of the opening of the mitochondrial ATP-sensitive K(+) channels. 相似文献
20.