scholarly journals A Subset of Odorant Receptors from the Desert Locust Schistocerca gregaria Is Co-Expressed with the Sensory Neuron Membrane Protein 1

Insects ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 350
Author(s):  
Pablo Pregitzer ◽  
Xingcong Jiang ◽  
René-Sebastian Lemke ◽  
Jürgen Krieger ◽  
Jörg Fleischer ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Sensory Neuron ◽  
Schistocerca Gregaria ◽  
Odorant Receptor ◽  
Phylogenetic Analyses ◽  
Desert Locust ◽  
Neuron Membrane ◽  
Group Iii ◽  
Group I ◽  
Sensory Neuron Membrane Protein

In the desert locust Schistocerca gregaria (S. gregaria), pheromones are considered to be crucial for governing important behaviors and processes, including phase transition, reproduction, aggregation and swarm formation. The receptors mediating pheromone detection in olfactory sensory neurons (OSNs) on the antenna of S. gregaria are unknown. Since pheromone receptors in other insects belong to the odorant receptor (OR) family and are typically co-expressed with the “sensory neuron membrane protein 1” (SNMP1), in our search for putative pheromone receptors of S. gregaria, we have screened the OR repertoire for receptor types that are expressed in SNMP1-positive OSNs. Based on phylogenetic analyses, we categorized the 119 ORs of S. gregaria into three groups (I–III) and analyzed a substantial number of ORs for co-expression with SNMP1 by two-color fluorescence in situ hybridization. We have identified 33 ORs that were co-expressed with SNMP1. In fact, the majority of ORs from group I and II were found to be expressed in SNMP1-positive OSNs, but only very few receptors from group III, which comprises approximately 60% of all ORs from S. gregaria, were co-expressed with SNMP1. These findings indicate that numerous ORs from group I and II could be important for pheromone communication. Collectively, we have identified a broad range of candidate pheromone receptors in S. gregaria that are not randomly distributed throughout the OR family but rather segregate into phylogenetically distinct receptor clades.

scholarly journals PPi-Dependent Phosphofructokinase fromThermoproteus tenax, an Archaeal Descendant of an Ancient Line in Phosphofructokinase Evolution

1998 ◽  
Vol 180 (8) ◽  
pp. 2137-2143 ◽  
Author(s):  
Bettina Siebers ◽  
Hans-Peter Klenk ◽  
Reinhard Hensel
Keyword(s):  
Streptomyces Coelicolor ◽  
Phylogenetic Analyses ◽  
Active Site Residues ◽  
Group Iii ◽  
Metabolic Intermediates ◽  
Physiological Conditions ◽  
Link Type ◽  
Group I ◽  
Key Enzyme ◽  
Thermoproteus Tenax

ABSTRACT Flux into the glycolytic pathway of most cells is controlled via allosteric regulation of the irreversible, committing step catalyzed by ATP-dependent phosphofructokinase (PFK) (ATP-PFK; EC 2.7.1.11 ), the key enzyme of glycolysis. In some organisms, the step is catalyzed by PPi-dependent PFK (PPi-PFK; EC 2.7.1.90 ), which uses PPi instead of ATP as the phosphoryl donor, conserving ATP and rendering the reaction reversible under physiological conditions. We have determined the enzymic properties of PPi-PFK from the anaerobic, hyperthermophilic archaeonThermoproteus tenax, purified the enzyme to homogeneity, and sequenced the gene. The ∼100-kDa PPi-PFK fromT. tenax consists of 37-kDa subunits; is not regulated by classical effectors of ATP-PFKs such as ATP, ADP, fructose 2,6-bisphosphate, or metabolic intermediates; and shares 20 to 50% sequence identity with known PFK enzymes. Phylogenetic analyses of biochemically characterized PFKs grouped the enzymes into three monophyletic clusters: PFK group I represents only classical ATP-PFKs from Bacteria and Eucarya; PFK group II contains only PPi-PFKs from the genusPropionibacterium, plants, and amitochondriate protists; whereas group III consists of PFKs with either cosubstrate specificity, i.e., the PPi-dependent enzymes from T. tenaxand Amycolatopsis methanolica and the ATP-PFK fromStreptomyces coelicolor. Comparative analyses of the pattern of conserved active-site residues strongly suggest that the group III PFKs originally bound PPi as a cosubstrate.

Ultrastructural Lesions Produced by Alcohol and Sucrose in the Heart and Liver of C57BL Mice

1970 ◽  
Vol 28 ◽  
pp. 208-209
Author(s):  
K.K. SEKHRI ◽  
C.S. ALEXANDER ◽  
H.T. NAGASAWA
Keyword(s):  
Osmium Tetroxide ◽  
Male Mice ◽  
Alcohol Group ◽  
Group Iii ◽  
Group I ◽  
C57bl Mice ◽  
Group Ii

C57BL male mice (Jackson Lab., Bar Harbor, Maine) weighing about 18 gms were randomly divided into three groups: group I was fed sweetened liquid alcohol diet (modified Schenkl) in which 36% of the calories were derived from alcohol; group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose; group III was fed regular mouse chow ad lib for five months. Liver and heart tissues were fixed in 2.5% cacodylate buffered glutaraldehyde, post-fixed in 2% osmium tetroxide and embedded in Epon-araldite.

The Quantitative Ultrastructure of the Heart Muscle of Japanese Quail by Hypergravitation, Hypodynamy and Combination

1990 ◽  
Vol 48 (3) ◽  
pp. 188-189
Author(s):  
Anton Bózner ◽  
Mikuláš Gažo ◽  
Jozef Dostál
Keyword(s):  
Japanese Quail ◽  
Heart Muscle ◽  
Relative Size ◽  
Combination Group ◽  
Control Group ◽  
Group V ◽  
Group Iii ◽  
Space Flights ◽  
Group I ◽  
Quantitative Ultrastructure

It is anticipated that Japanese quail /Coturnix coturnix japonica/ will provide animal proteins in long term space flights. Consequently this species of birds is of research interest of international space program INTERCOSMOS. In the year 1987 we reported on an experiment /2/ in which the effect of chronic acceleration of 2 G hypergravitation, the hypodynamy and the simultaneous effect of chronic acceleration and the location in the centre of the turntable of the centrifuge on the protein fractions in skeletal muscles was studied. The ultrastructure of the heart muscle was now in this experiments examined as well.Japanese quail cockerels, aged 48 days were exposed to 2 G hypergravitation /group IV/ in a 6,4 m diameter centrifuge, to hypodynamy /group III/ and their combination /group V/, respectively for 6 days / Fig.1/. The hypodynamy in group III was achieved by suspending the birds in jackets without contact the floor. The group II was located in the centre ofthe turntable of the centrifuge. The control group I. was kept under normal conditions. The quantitative ultrastructure of myocard was evaluated by the methods of Weibel/3/ - this enables to determine the number, relative size and volume of mitochondria volume of single mitochondria, defficiency of mitochondrial cristae and volume of myofibrils.

Heterogeneity and Immunochemical Properties of Anti-β2-glycoprotein I Autoantibodies

1998 ◽  
Vol 80 (09) ◽  
pp. 393-398 ◽  
Author(s):  
V. Regnault ◽  
E. Hachulla ◽  
L. Darnige ◽  
B. Roussel ◽  
J. C. Bensa ◽  
...  
Keyword(s):  
Fluid Phase ◽  
Anticardiolipin Antibodies ◽  
Dual Reactivity ◽  
Group Iii ◽  
Important Group ◽  
Epitope Specificity ◽  
Glycoprotein I ◽  
Group I ◽  
Group Ii ◽  
Sufficient Concentration

SummaryMost anticardiolipin antibodies (ACA) associated with antiphospholipid syndrome (APS) are directed against epitopes expressed on β2-glycoprotein I (β2GPI). Despite a good correlation between standard ACA assays and those using purified human β2GPI as the sole antigen, some sera from APS patients only react in the latter. This is indicative of heterogeneity in anti-β2GPI antibodies. To characterize their reactivity profiles, human and bovine β2GPI were immobilized on γ-irradiated plates (β2GPI-ELISA), plain polystyrene precoated with increasing cardiolipin concentrations (CL/β2GPI-ELISA), and affinity columns. Fluid-phase inhibition experiments were also carried out with both proteins. Of 56 selected sera, restricted recognition of bovine or human β2GPI occurred respectively in 10/29 IgA-positive and 9/22 IgM-positive samples, and most of the latter (8/9) were missed by the standard ACA assay, as expected from a previous study. Based on species specificity and ACA results, IgG-positive samples (53/56) were categorized into three groups: antibodies reactive to bovine β2GPI only (group I) or to bovine and human β2GPI, group II being ACA-negative, and group III being ACA-positive. The most important group, group III (n = 33) was characterized by (i) binding when β2GPI was immobilized on γ-irradiated polystyrene or cardiolipin at sufficient concentration (regardless of β2GPI density, as assessed using 125I-β2GPI); (ii) and low avidity binding to fluid-phase β2GPI (Kd in the range 10–5 M). In contrast, all six group II samples showed (i) ability to bind human and bovine β2GPI immobilized on non-irradiated plates; (ii) concentration-dependent blockade of binding by cardiolipin, suggesting epitope location in the vicinity of the phospholipid binding site on native β2GPI; (iii) and relative avidities approximately 100-fold higher than in group III. Group I patients were heterogeneous with respect to CL/β2GPI-ELISA and ACA results (6/14 scored negative), possibly reflecting antibody differences in terms of avidity and epitope specificity. Affinity fractionation of 23 sera showed the existence, in individual patients, of various combinations of antibody subsets solely reactive to human or bovine β2GPI, together with cross-species reactive subsets present in all samples with dual reactivity namely groups III and II, although the latter antibodies were poorly purified on either column. Therefore, the mode of presentation of β2GPI greatly influences its recognition by anti-β2GPI antibodies with marked inter-individual heterogeneity, in relation to ACA quantitation and, possibly, disease presentation and pathogenesis.

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