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991.
da Silva Mendes Johnatan Wellisson Cunha Walmir Emanuel Miranda Rodrigues Fábio Fernandes Galvão Silveira Edilberto Rocha de Lima Roberta Dávila Pereira da Costa José Galberto Martins 《Phytochemistry Reviews》2020,19(4):955-982
Phytochemistry Reviews - Species of Cissampelos (Menispermaceae) are widely used in folk medicine in various cultures, for the treatment of a wide variety of diseases. Several ethnobotanical... 相似文献
992.
Gabriela R. Villeth Fabio B. Reis Jr Angela Tonietto Luciano Huergo Emanuel M. de Souza Fabio O. Pedrosa Octávio L. Franco & Angela Mehta 《FEMS microbiology letters》2009,298(2):260-266
Black rot of cruciferous plants, caused by Xanthomonas campestris pv. campestris , causes severe losses in agriculture around the world. This disease affects several cultures, including cabbage and broccoli, among others. Proteome studies of this bacterium have been reported; however, most of them were performed using the bacterium grown under culture media conditions. Recently, we have analyzed the proteome of X. campestris pv. campestris during the interaction with the susceptible cultivar of Brassica oleracea and several proteins were identified. The objective of the present study was to analyze the expressed proteins of X. campestris pv. campestris during the interaction with the resistant cultivar of B. oleracea . The bacterium was infiltrated in the leaves of the resistant plant and recovered for protein extraction and two-dimensional electrophoresis. The protein profile was compared with that of the bacterium isolated from the susceptible host and the results obtained revealed a group of proteins exclusive to the resistant interaction. Among the proteins identified in this study were plant and bacterium proteins, some of which were exclusively expressed during the resistant interaction. 相似文献
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Catechol-O-methyltransferase (COMT; EC 2.1.1.6) is a physiologically important enzyme in the metabolism of catecholamine neurotransmitters and catechol drugs. Using primers derived from the known rat cDNA sequence for COMT, we have used the polymerase chain reaction to produce an amplified DNA fragment corresponding to the complete coding region of the rat gene. With this fragment as a probe, we have hybridized DNAs from two panels consisting of human/rodent and human/hamster somatic cell hybrids carrying various translocations and deletions to refine the chromosomal location of human COMT. Southern blot analysis indicates that the human COMT gene is localized to 22q11.1----q11.2, a region to which several anonymous DNA sequences, but until now, no structural genes, have been assigned. 相似文献
996.
Emanuel Wyler Franziska Wandrey Lukas Badertscher Christian Montellese Daniel Alper Ulrike Kutay 《FEBS letters》2014
BRCA2 and CDKN1A(p21,CIP1)-interacting protein (BCCIP) is an evolutionary conserved protein implicated in maintenance of genome stability and cell cycle progression. Two isoforms of BCCIP with distinct C-terminal domains exist in humans. We show that mammalian BCCIPβ, but not BCCIPα, forms a ternary complex with the ribosomal protein RPL23/uL14 and the pre-60S trans-acting factor eIF6. Complex formation is dependent on an intact C-terminal domain of BCCIPβ. Depletion of BCCIPβ reduces the pool of free RPL23, and decreases eIF6 levels in nucleoli. Overexpression of BCCIPβ leads to nucleoplasmic accumulation of extra-ribosomal RPL23 and stabilizes overexpressed RPL23, suggesting that BCCIPβ functions as nuclear chaperone for RPL23. 相似文献
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Sarthak P. Malusare Giacomo Zilio Emanuel A. Fronhofer 《Journal of evolutionary biology》2023,36(1):15-28
Temperatures are increasing due to global changes, putting biodiversity at risk. Organisms are faced with a limited set of options to cope with this situation: adapt, disperse or die. We here focus on the first possibility, more specifically, on evolutionary adaptations to temperature. Ectotherms are usually characterized by a hump-shaped relationship between fitness and temperature, a non-linear reaction norm that is referred to as thermal performance curve (TPC). To understand and predict impacts of global change, we need to know whether and how such TPCs evolve. Therefore, we performed a systematic literature search and a statistical meta-analysis focusing on experimental evolution and artificial selection studies. This focus allows us to directly quantify relative fitness responses to temperature selection by calculating fitness differences between TPCs from ancestral and derived populations after thermal selection. Out of 7561 publications screened, we found 47 studies corresponding to our search criteria representing taxa across the tree of life, from bacteria, to plants and vertebrates. We show that, independently of species identity, the studies we found report a positive response to temperature selection. Considering entire TPC shapes, adaptation to higher temperatures traded off with fitness at lower temperatures, leading to niche shifts. Effects were generally stronger in unicellular organisms. By contrast, we do not find statistical support for the often discussed “Hotter is better” hypothesis. While our meta-analysis provides evidence for adaptive potential of TPCs across organisms, it also highlights that more experimental work is needed, especially for under-represented taxa, such as plants and non-model systems. 相似文献
999.
Jér?me Cabana Brian Holleran Richard Leduc Emanuel Escher Gaétan Guillemette Pierre Lavigne 《The Journal of biological chemistry》2015,290(25):15835-15854
Biased signaling represents the ability of G protein-coupled receptors to engage distinct pathways with various efficacies depending on the ligand used or on mutations in the receptor. The angiotensin-II type 1 (AT1) receptor, a prototypical class A G protein-coupled receptor, can activate various effectors upon stimulation with the endogenous ligand angiotensin-II (AngII), including the Gq/11 protein and β-arrestins. It is believed that the activation of those two pathways can be associated with distinct conformations of the AT1 receptor. To verify this hypothesis, microseconds of molecular dynamics simulations were computed to explore the conformational landscape sampled by the WT-AT1 receptor, the N111G-AT1 receptor (constitutively active and biased for the Gq/11 pathway), and the D74N-AT1 receptor (biased for the β-arrestin1 and -2 pathways) in their apo-forms and in complex with AngII. The molecular dynamics simulations of the AngII-WT-AT1, N111G-AT1, and AngII-N111G-AT1 receptors revealed specific structural rearrangements compared with the initial and ground state of the receptor. Simulations of the D74N-AT1 receptor revealed that the mutation stabilizes the receptor in the initial ground state. The presence of AngII further stabilized the ground state of the D74N-AT1 receptor. The biased agonist [Sar1,Ile8]AngII also showed a preference for the ground state of the WT-AT1 receptor compared with AngII. These results suggest that activation of the Gq/11 pathway is associated with a specific conformational transition stabilized by the agonist, whereas the activation of the β-arrestin pathway is linked to the stabilization of the ground state of the receptor. 相似文献
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