Search results for "genetics [Transcriptome]"

Structural mechanism of signal transduction in a phytochrome histidine kinase

2022

AbstractPhytochrome proteins detect red/far-red light to guide the growth, motion, development and reproduction in plants, fungi, and bacteria. Bacterial phytochromes commonly function as an entrance signal in two-component sensory systems. Despite the availability of three-dimensional structures of phytochromes and other two-component proteins, the conformational changes, which lead to activation of the protein, are not understood. We reveal cryo electron microscopy structures of the complete phytochrome from Deinoccocus radiodurans in its resting and photoactivated states at 3.6 Å and 3.5 Å resolution, respectively. Upon photoactivation, the photosensory core module hardly changes its ter…

The Striking Case of Tryptophan Provision in the Cedar Aphid Cinara cedri

2008

ABSTRACT Buchnera aphidicola BCc has lost its symbiotic role as the tryptophan supplier to the aphid Cinara cedri . We report the presence of a plasmid in this endosymbiont that contains the trpEG genes. The remaining genes for the pathway ( trpDCBA ) are located on the chromosome of the secondary endosymbiont “ Candidatus Serratia symbiotica.” Thus, we propose that a symbiotic consortium is necessary to provide tryptophan.

Binding Sites for Neurotoxins and Cholinergic Ligands in Peripheral and Neuronal Nicotinic Receptors Studies with Synthetic Receptor Sequencesa

1995

Unusual conformations of 1,3-dialkoxythiacalix[4]arenes in the solid state

2006

The structures of three syn-1,3-dialkoxythiacalix[4]arenes with unusual conformations in the solid state are reported. The pinched cone conformation of syn-2 2 ,4 2 -dihydroxy-1 2 ,3 2 -bis-(prop-2-enyloxy)thiacalix[4]arene, C 30 H 24 O 4 S 4 , (3a), is stabilized by two intramolecular hydrogen bonds, remarkably formed from both OH groups to the same ether O atom. In syn-22,42-dihydroxy-1 5 ,2 5 ,3 5 ,4 5 -tetranitro-12,32-bis(prop-2-enyloxy)thiacalix[4]arene acetone disolvate, C 30 H 20 N 4 O 12 S 4 ·-2C 3 H 6 O, (3b1), the molecule is found in the 1,3-alternate conformation. The crystallographic C2 symmetry is due to a twofold rotation axis running through the centre of the calixarene rin…

Micelles, Rods, Liposomes, and Other Supramolecular Surfactant Aggregates: Computational Approaches

2017

Surfactants are an interesting class of compounds characterized by the segregation of polar and apolar domains in the same molecule. This peculiarity makes possible a whole series of microscopic and macroscopic effects. Among their features, their ability to segregate particles (fluids or entire domains) and to reduce the surface/interfacial tension is the utmost important. The interest in the chemistry of surfactants never weakened; instead, waves of increasing interest have occurred every time a new field of application of these molecules has been discovered. All these special characteristics depend largely on the ability of surfactants to self-assemble and constitute supramolecular struc…

Independence between developmental stability and canalization in the skull of the house mouse.

2000

The relationship between the two components of developmental homeostasis, that is canalization and developmental stability (DS), is currently debated. To appraise this relationship, the levels and morphological patterns of interindividual variation and fluctuating asymmetry were assessed using a geometric morphometric approach applied to the skulls of laboratory samples of the house mouse. These three samples correspond to two random-bred strains of the two European subspecies of the house mouse and their F1 hybrids. The inter- and intraindividual variation levels were found to be smaller in the hybrid group compared to the parental ones, suggesting a common heterotic effect on skull canali…

L’audition chez les primates : entre forme, fonction, écologie et comportement

2019

The order Primates is composed of species whose morphologies, life history traits and behaviors are very diversified. The oldest representatives are dated about 65 million years. Because of this diversity, studies have focused on understanding the relationships between different parameters. Among the morphological structures studied, the basicranium, in particular the characters of the ear, have very often been considered in a phylogenetic perspective. Since the development of new acquisition techniques such as micro-tomography (μCT), new data are available. Thus, the interest for the morphology of the inner and middle ear, hitherto difficult to access, is growing. The structures of the ear…

Differential Greek and northern African migrations to Sicily are supported by genetic evidence from the Y chromosome

2009

The presence or absence of genetic heterogeneity in Sicily has long been debated. Through the analysis of the variation of Y-chromosome lineages, using the combination of haplogroups and short tandem repeats from several areas of Sicily, we show that traces of genetic flows occurred in the island, due to ancient Greek colonization and to northern African contributions, are still visible on the basis of the distribution of some lineages. The genetic contribution of Greek chromosomes to the Sicilian gene pool is estimated to be about 37% whereas the contribution of North African populations is estimated to be around 6%. In particular, the presence of a modal haplotype coming from the southern…

Procedural learning and prefrontal cortex.

1995

The NFκB-inducing kinase is essential for the developmental programming of skin-resident and IL-17-producing γδ T cells

2015

γδ T cells contribute to first line immune defense, particularly through their ability for rapid production of proinflammatory cytokines. The cytokine profile of γδ T cells is hard-wired already during thymic development. Yet, the molecular pathways underlying this phenomenon are incompletely understood. Here we show that signaling via the NFκB-inducing kinase (NIK) is essential for the formation of a fully functional γδ T cell compartment. In the absence of NIK, development of Vγ5+ dendritic epidermal T cells (DETCs) was halted in the embryonic thymus, and impaired NIK function caused a selective loss of IL-17 expression by γδ T cells. Using a novel conditional mutant of NIK, we could show…