Morphology, distribution and abundance of antennal sensilla in four ant species (Hymenoptera: Formicidae) having mutualistic relationship with aphids

The early development of antenna and antennal sensilla in the noctuid moth, Agrotis segetum (Insecta: Lepidoptera)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160066 ◽

1990 ◽

Vol 48 (3) ◽

pp. 502-503

Author(s):

Eric Hallberg ◽

Lina Hansén

Keyword(s):

Cell Death ◽

Stem Cell ◽

Early Development ◽

Larval Stage ◽

Pupal Stage ◽

Agrotis Segetum ◽

Antennal Sensilla ◽

Noctuid Moth ◽

Standard Procedures

The antennal rudiments in lepidopterous insects are present as disks during the larval stage. The tubular double-walled antennal disk is present beneath the larval antenna, and its inner layer gives rise to the adult antenna during the pupal stage. The sensilla develop from a cluster of cells that are derived from one stem cell, which gives rise to both sensory and enveloping cells. During the morphogenesis of the sensillum these cells undergo major transformations, including cell death. In the moth Agrotis segetum the pupal stage lasts about 14 days (temperature, 25°C). The antennae, clearly seen from the exterior, were dissected and fixed according to standard procedures (3 % glutaraldehyde in 0.15 M cacaodylate buffer, followed by 1 % osmiumtetroxide in the same buffer). Pupae from day 1 to day 8, of both sexes were studied.

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Bacteriophages as drivers of bacterial virulence and their potential for biotechnological exploitation

FEMS Microbiology Reviews ◽

10.1093/femsre/fuaa041 ◽

2020 ◽

Author(s):

Kaat Schroven ◽

Abram Aertsen ◽

Rob Lavigne

Keyword(s):

Small Molecules ◽

Bacterial Infections ◽

Bacterial Virulence ◽

Arms Race ◽

Control Mechanisms ◽

Human Pathogens ◽

Vaccine Candidates ◽

Cargo Proteins ◽

Genes Encoding ◽

Mutualistic Relationship

ABSTRACT Bacteria-infecting viruses (phages) and their hosts maintain an ancient and complex relationship. Bacterial predation by lytic phages drives an ongoing phage-host arms race, whereas temperate phages initiate mutualistic relationships with their hosts upon lysogenization as prophages. In human pathogens, these prophages impact bacterial virulence in distinct ways: by secretion of phage-encoded toxins, modulation of the bacterial envelope, mediation of bacterial infectivity and the control of bacterial cell regulation. This review builds the argument that virulence-influencing prophages hold extensive, unexplored potential for biotechnology. More specifically, it highlights the development potential of novel therapies against infectious diseases, to address the current antibiotic resistance crisis. First, designer bacteriophages may serve to deliver genes encoding cargo proteins which repress bacterial virulence. Secondly, one may develop small molecules mimicking phage-derived proteins targeting central regulators of bacterial virulence. Thirdly, bacteria equipped with phage-derived synthetic circuits which modulate key virulence factors could serve as vaccine candidates to prevent bacterial infections. The development and exploitation of such antibacterial strategies will depend on the discovery of other prophage-derived, virulence control mechanisms and, more generally, on the dissection of the mutualistic relationship between temperate phages and bacteria, as well as on continuing developments in the synthetic biology field.

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Morphological Characterization of the Antennal Sensilla of the Afrotropical Sand Fly, Phlebotomus duboscqi (Diptera: Psychodidae)

Journal of Medical Entomology ◽

10.1093/jme/tjaa247 ◽

2020 ◽

Author(s):

Ana Cristina Bahia ◽

Ana Beatriz F Barletta ◽

Luciana Conceição Pinto ◽

Alessandra S Orfanó ◽

Rafael Nacif-Pimenta ◽

...

Keyword(s):

Morphological Characters ◽

Morphological Characterization ◽

Sand Fly ◽

Antennal Sensilla ◽

Olfactory Sensilla ◽

Zoonotic Cutaneous Leishmaniasis ◽

Electrophysiological Studies ◽

Phlebotomus Duboscqi ◽

Well Differentiated ◽

Function Number

Abstract We investigated by scanning electron microscopy the morphology, distribution, and abundance of antennal sensilla of females Phlebotomus duboscqi sand fly, an important vector of zoonotic cutaneous leishmaniasis at Afrotropical region. Thirteen well-differentiated sensilla were identified, among six types of cuticular sensilla. The probable function of these sensillary types is discussed in relation to their external structure and distribution. Five sensillary types were classified as olfactory sensilla, as they have specific morphological characters of sensilla with this function. Number and distribution of sensilla significantly differed between antennal segments. The results of the present work, besides corroborating in the expansion of the morphological and ultrastructural knowledge of P. duboscqi, can foment future electrophysiological studies for the development of volatile semiochemicals, to be used as attractants in traps for monitoring and selective vector control of this sand fly.

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Fine Morphology of Antennal and Ovipositor Sensory Structures of the Gall Chestnut Wasp, Dryocosmus kuriphilus

Insects ◽

10.3390/insects12030231 ◽

2021 ◽

Vol 12 (3) ◽

pp. 231

Author(s):

Milos Sevarika ◽

Marco Valerio Rossi Stacconi ◽

Roberto Romani

Keyword(s):

Ultrastructural Organization ◽

Antennal Sensilla ◽

Dryocosmus Kuriphilus ◽

Transmission Electron ◽

Significant Damage ◽

Sensory Structures ◽

Host Plant Location ◽

Oviposition Sites ◽

Fine Morphology

Dryocosmus kuriphilus is a gall-inducing insect, which can cause significant damage on plants of the genus Castanea Mill., 1754. Antennae and ovipositor are the main sensory organs involved in the location of suitable oviposition sites. Antennal sensilla are involved in the host plant location, while ovipositor sensilla assess the suitability of the ovipositional bud. On both organs, diverse sensillar organs are present. Here, the distribution and ultrastructural organization of the sensilla were investigated by scanning and transmission electron microscopy. The antennae of D. kuriphilus are filiform and composed of 14 antennomeres, with the distal flagellomere bearing the highest number of sensilla. On the antennae, 6 sensilla types were found; sensilla chaetica, campaniformia, coeloconica-I, coeloconica-II, trichoidea and placoidea. The sensilla placoidea and trichoidea were the most abundant types. On the external walls of the ovipositor, gustatory and mechanoreceptive sensilla were observed. Internally, the egg channel hosted two additional sensory structures. The putative functional role of each sensilla in the context of insect’s ecology is discussed as well as the ovipositional mechanism used by this insect.

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Diarrhea Predominant-Irritable Bowel Syndrome (IBS-D): Effects of Different Nutritional Patterns on Intestinal Dysbiosis and Symptoms

Nutrients ◽

10.3390/nu13051506 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1506

Author(s):

Annamaria Altomare ◽

Claudia Di Rosa ◽

Elena Imperia ◽

Sara Emerenziani ◽

Michele Cicala ◽

...

Keyword(s):

Irritable Bowel Syndrome ◽

Intestinal Microbiota ◽

Gastrointestinal Disorder ◽

Additional Energy ◽

Nutritional Advice ◽

Intestinal Dysbiosis ◽

Gi Symptoms ◽

Mutualistic Relationship ◽

Irritable Bowel ◽

Fodmap Diet

Irritable Bowel Syndrome (IBS) is a chronic functional gastrointestinal disorder characterized by abdominal pain associated with defecation or a change in bowel habits. Gut microbiota, which acts as a real organ with well-defined functions, is in a mutualistic relationship with the host, harvesting additional energy and nutrients from the diet and protecting the host from pathogens; specific alterations in its composition seem to play a crucial role in IBS pathophysiology. It is well known that diet can significantly modulate the intestinal microbiota profile but it is less known how different nutritional approach effective in IBS patients, such as the low-FODMAP diet, could be responsible of intestinal microbiota changes, thus influencing the presence of gastrointestinal (GI) symptoms. The aim of this review was to explore the effects of different nutritional protocols (e.g., traditional nutritional advice, low-FODMAP diet, gluten-free diet, etc.) on IBS-D symptoms and on intestinal microbiota variations in both IBS-D patients and healthy subjects. To date, an ideal nutritional protocol does not exist for IBS-D patients but it seems crucial to consider the effect of the different nutritional approaches on the intestinal microbiota composition to better define an efficient strategy to manage this functional disorder.

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Symbiotic Nitrogen Fixation and the Challenges to Its Extension to Nonlegumes

Applied and Environmental Microbiology ◽

10.1128/aem.01055-16 ◽

2016 ◽

Vol 82 (13) ◽

pp. 3698-3710 ◽

Cited By ~ 193

Author(s):

Florence Mus ◽

Matthew B. Crook ◽

Kevin Garcia ◽

Amaya Garcia Costas ◽

Barney A. Geddes ◽

...

Keyword(s):

Nitrogen Fixation ◽

Synthetic Biology ◽

Biological Nitrogen Fixation ◽

Symbiotic Nitrogen Fixation ◽

Crop Plants ◽

Symbiotic Relationships ◽

Mutualistic Relationship ◽

Interest In Research ◽

Biological Nitrogen ◽

Developed World

ABSTRACTAccess to fixed or available forms of nitrogen limits the productivity of crop plants and thus food production. Nitrogenous fertilizer production currently represents a significant expense for the efficient growth of various crops in the developed world. There are significant potential gains to be had from reducing dependence on nitrogenous fertilizers in agriculture in the developed world and in developing countries, and there is significant interest in research on biological nitrogen fixation and prospects for increasing its importance in an agricultural setting. Biological nitrogen fixation is the conversion of atmospheric N2to NH3, a form that can be used by plants. However, the process is restricted to bacteria and archaea and does not occur in eukaryotes. Symbiotic nitrogen fixation is part of a mutualistic relationship in which plants provide a niche and fixed carbon to bacteria in exchange for fixed nitrogen. This process is restricted mainly to legumes in agricultural systems, and there is considerable interest in exploring whether similar symbioses can be developed in nonlegumes, which produce the bulk of human food. We are at a juncture at which the fundamental understanding of biological nitrogen fixation has matured to a level that we can think about engineering symbiotic relationships using synthetic biology approaches. This minireview highlights the fundamental advances in our understanding of biological nitrogen fixation in the context of a blueprint for expanding symbiotic nitrogen fixation to a greater diversity of crop plants through synthetic biology.

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