1. Integument

Chauvin, G.; Kristensen, Niels P.

doi:10.1515/9783110893724.1

Cited by 4 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Micropterix it covers the whole larval trunk except for the abdominal appendage tips; by Hamon and Chauvin () it was considered to be detached epicuticle (an interpretation also reflected by the labelling of Fig. 1.4L in Chauvin and Kristensen, ). Hamon and Chauvin noted the presence of foreign bodies resembling bacteria and algae, another similarity with conditions in Sabatinca .…”

Section: Discussionmentioning

confidence: 95%

“…Further questions concern the nature and function of the fluid in the intracuticular space/exocuticular chambers; here obviously development of techniques for analyzing its composition, and temporal variation (if any) in the latter, will prove crucial. Suggestions (Kristensen, ; Chauvin and Kristensen, ) that the fluid might have predator‐deterrent properties and/or contribute to maintaining water‐balance in periods of dessication are straightforward, but pure conjectures. What does seem almost certain is that, at least periodically, the dorsal/lateral chambers contain precursors of the pellicle.…”

Section: Discussionmentioning

confidence: 99%

“…In previously examined micropterigid larvae surface, specializations on the lateral trunk cuticle including the spiracles have been interpreted as likely plastron-forming structures, as described in most detail by Davis and Landry (2012) following previous suggestions (Davis, 1987;Hamon and Chauvin, 1995;Chauvin and Kristensen, 2003). A plastron is a constant-volume air film maintaining a permanent oxygen-carbon dioxide exchange surface (Flynn and Bush, 2008;Shirtcliffe et al, 2006).…”

Section: Integumentmentioning

confidence: 96%

“…Some aspects of its surface structure have been illustrated in scanning electron micrographs (SEM; Davis 1987;Hamon and Chauvin, 1995;Hashimoto 2001Hashimoto , 2006Davis and Landry, 2012), but it is the internal cuticular structure, particularly the chambered exocuticle and the open space between endocuticle and exocuticle, which renders the integument unique at the arthropod level. The striking specializations in question long remained described only in a very preliminary way (Kristensen, 1984a(Kristensen, , 1990, and also the later more substantial accounts (Hamon and Chauvin, 1995;Chauvin and Kristensen, 2003;Davis and Landry, 2012) are of a nondefinitive nature; records of the marked differences around the trunk periphery were only very recently published (Dupont, 2010;Davis and Landry, 2012).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Chambered cuticle, pellicles, strange sensilla, and extraordinary muscle arrangements: A study of the micropterigid larval trunk (Lepidoptera: Micropterigidae)

Dupont

2014

Journal of Morphology

View full text Add to dashboard Cite

The larvsal trunk wall of Sabatinca chalcophanes (Meyrick, 1885), representing the "sabatincoid morphotype," is described (brightfield and polarization microscopies, scanning and transmission electron microscopies). Eight sensillum types are identified, including four previously undescribed subventral and ventral kinds. The cuticle is nonsolid, the exocuticle being chambered in a honeycomb-like fashion with chamber walls apparently secreted along epidermal cells boundaries. The chamber contents open to the exterior via minute pores in the chamber roofs. A space between endo and exocuticle communicates with the chamber interiors via pores in the chamber floors; the dense endocuticular surface in places form thickened domes. On the lower trunk region, lateral chamber walls are highly porous (lattice like), hence their contents are continuous; individual chamber roofs here are markedly convex, and the external trunk surface, therefore, papillate. The trunk surface is more or less completely covered by a pellicle, likely formed by exudates from the exocuticular chambers. Unusually for Lepidoptera all trunk muscles are slender strands covering a modest proportion of the inner trunk surface. Conspicuous insertion "nodes" are located at lateral and ventral segmental boundaries, ventromedially near segmental midlengths, and paramedially on the dorsum behind segmental midlengths. Overall similar cuticular specializations are also present in the distantly related Micropterix, strongly supporting micropterigid monophyly.

show abstract

Section: Discussionmentioning

confidence: 95%

Section: Discussionmentioning

confidence: 99%

Section: Integumentmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Chambered cuticle, pellicles, strange sensilla, and extraordinary muscle arrangements: A study of the micropterigid larval trunk (Lepidoptera: Micropterigidae)

Dupont

2014

Journal of Morphology

View full text Add to dashboard Cite

show abstract

Partner-specific induction ofSpodoptera frugiperdaimmune genes in response to the entomopathogenic nematobacterial complexSteinernema carpocapsae-Xenorhabdus nematophila

Huot

Bigourdan

Pagès

et al. 2019

Preprint

View full text Add to dashboard Cite

13The Steinernema carpocapsae-Xenorhabdus nematophila association is a nematobacterial complex (NBC) 14 used in biological control of insect crop pests. The ability of this dual pathogen to infest and kill an insect 15 strongly depends on the dialogue between the host's immune system and each partner of the complex. Even 16 though this dialogue has been extensively studied from the two partners' points of view in several insect 17 models, still little is known about the structure and the molecular aspects of the insects' immune response 18 to the dual infection. Here, we used the lepidopteran pest Spodoptera frugiperda as a model to analyze the 19 respective impact of each NBC partner in the spatiotemporal immune responses that are induced after 20 infestation. To this aim, we first analyzed the expression variations of the insect's immune genes in the fat 21 bodies and hemocytes of infested larvae by using previously obtained RNAseq data. We then selected 22 representative immune genes for RT-qPCR investigations of the temporal variations of their expressions 23 after infestation and of their induction levels after independent injections of each partner. We found that 24 the fat body and the hemocytes both produce potent and stable immune responses to the infestation by the 25 NBC, which correspond to combinations of bacterium-and nematode-induced ones. Consistent with the 26 nature of each pathogen, we showed that X. nematophila mainly induces genes classically involved in 27 antibacterial responses, whereas S. carpocapsae is responsible for the induction of lectins and of genes 28 expected to be involved in melanization and cellular encapsulation. In addition, we found that two clusters 29 of unknown genes dramatically induced by the NBC also present partner-specific induction profiles, which 30 paves the way for their functional characterization. Finally, we discuss putative relationships between the 31 variations of the expression of some immune genes and the NBC's immunosuppressive strategies. 32 3 33Author summary 34 Entomopathogenic nematodes (EPNs) are living in the soil and prey upon insect larvae. They enter the 35 insect by the natural orifices, and reach the hemocoel through the intestinal epithelium. There, they release 36 their symbiotic bacteria that will develop within the insect and eventually kill it. Nematodes can then feed 37 and reproduce on the insect cadaver. By using transcriptomic approaches, we previously showed that 38 Lepidoptera larvae (caterpillars of the fall armyworm Spodoptera frugiperda) produce a strong immune 39 response in reaction to infestation by EPNs. However, we do not know if this immune reaction is triggered 40 by the nematode itself -Steinernema carpacapsae -or its symbiotic bacteria -Xenorhabdus nematophila. 41 To answer this question, we present in this work a careful annotation of immunity genes in S. frugiperda 42 and surveyed their activation by quantitative PCR in reaction to an injection of the bacteria alone, the axenic 43 nematode or the ...

show abstract

In Memoriam: Niels Peder Kristensen (1943–2014)

Karsholt¹,

Scoble²

2015

View full text Add to dashboard Cite

, Honorary Member and former president of SEL, passed away on Saturday December 6 th 2014 in Copenhagen. While his death was not unexpected, its timing came earlier than we had thought or hoped. His loss is felt widely and intensely. Born on March 2 nd 1943, Niels was the second child of Thorkil and Ellen Christine Kristensen (nee Nielsen). His father was an academic, politician and thinker who served as Minster of Finance in two different government cabinets, and later as General Secretary of the OECD. Growing up in such an environment undoubtedly had a profound influence on Niels' own world view, one which was powerfully international in its expression, yet retaining a strong interest and deep concern for Danish issues-local and national. Niels developed an interest in entomology and lepidopterology in particular at an early age, and once told TJS about the first time, when eight years old, he visited the Entomology Department at the Zoological Museum in Copenhagen (ZMUC) 'clutching his father's hand'. After completing high school at Birkerød Statsskole in 1961, Niels enrolled as a biology student at the University of Copenhagen, and quickly became a regular visitor to the Entomology Department of the Museum, where he had already started as a volunteer during his last years at high school. In 1965, while still a student, he published his first paper, which was on the faunistics of Danish cicadas. From the very start of his scientific career, one of Niels' abiding interests was the evolution (particularly evolutionary morphology) of primitive Lepidoptera. Indeed, the work for his Mag. Scient. degree was on the comparative morphology of the primitive glossatan family, Eriocraniidae. During this study, Niels spent the academic year 1966-67 at the University of

show abstract

1. Integument

Cited by 4 publications

References 13 publications

Chambered cuticle, pellicles, strange sensilla, and extraordinary muscle arrangements: A study of the micropterigid larval trunk (Lepidoptera: Micropterigidae)

Chambered cuticle, pellicles, strange sensilla, and extraordinary muscle arrangements: A study of the micropterigid larval trunk (Lepidoptera: Micropterigidae)

Partner-specific induction ofSpodoptera frugiperdaimmune genes in response to the entomopathogenic nematobacterial complexSteinernema carpocapsae-Xenorhabdus nematophila

In Memoriam: Niels Peder Kristensen (1943–2014)

Contact Info

Product

Resources

About