Search results for "Vertebrate"

Are dendrites in Drosophila homologous to vertebrate dendrites?

2005

AbstractDendrites represent arborising neurites in both vertebrates and invertebrates. However, in vertebrates, dendrites develop on neuronal cell bodies, whereas in higher invertebrates, they arise from very different neuronal structures, the primary neurites, which also form the axons. Is this anatomical difference paralleled by principal developmental and/or physiological differences? We address this question by focussing on one cellular model, motorneurons of Drosophila and characterise the compartmentalisation of these cells. We find that motorneuronal dendrites of Drosophila share with typical vertebrate dendrites that they lack presynaptic but harbour postsynaptic proteins, display c…

Neuroblast formation and patterning during early brain development in Drosophila.

2004

The Drosophila embryo provides a useful model system to study the mechanisms that lead to pattern and cell diversity in the central nervous system (CNS). The Drosophila CNS, which encompasses the brain and the ventral nerve cord, develops from a bilaterally symmetrical neuroectoderm, which gives rise to neural stem cells, called neuroblasts. The structure of the embryonic ventral nerve cord is relatively simple, consisting of a sequence of repeated segmental units (neuromeres), and the mechanisms controlling the formation and specification of the neuroblasts that form these neuromeres are quite well understood. Owing to the much higher complexity and hidden segmental organization of the bra…

The

2016

ABSTRACT Members of the Junctophilin (JPH) protein family have emerged as key actors in all excitable cells, with crucial implications for human pathophysiology. In mammals, this family consists of four members (JPH1-JPH4) that are differentially expressed throughout excitable cells. The analysis of knockout mice lacking JPH subtypes has demonstrated their essential contribution to physiological functions in skeletal and cardiac muscles and in neurons. Moreover, mutations in the human JPH2 gene are associated with hypertrophic and dilated cardiomyopathies; mutations in JPH3 are responsible for the neurodegenerative Huntington's disease-like-2 (HDL2), whereas JPH1 acts as a genetic modifier …

Established cotton stainer gut bacterial mutualists evade regulation by host antimicrobial peptides

2019

Symbioses with microorganisms are ubiquitous in nature and confer important ecological traits to animal hosts but also require control mechanisms to ensure homeostasis of the symbiotic interactions. In addition to protecting hosts against pathogens, animal immune systems recognize, respond to, and regulate mutualists. The gut bacterial symbionts of the cotton stainer bug, Dysdercus fasciatus, elicit an immune response characterized by the upregulation of c-type lysozyme and the antimicrobial peptide pyrrhocoricin in bugs with their native gut microbiota compared to that in dysbiotic insects. In this study, we investigated the impact of the elicited antimicrobial immune response on the estab…

Classification and retrieval on macroinvertebrate image databases

2011

Aquatic ecosystems are continuously threatened by a growing number of human induced changes. Macroinvertebrate biomonitoring is particularly efficient in pinpointing the cause-effect structure between slow and subtle changes and their detrimental consequences in aquatic ecosystems. The greatest obstacle to implementing efficient biomonitoring is currently the cost-intensive human expert taxonomic identification of samples. While there is evidence that automated recognition techniques can match human taxa identification accuracy at greatly reduced costs, so far the development of automated identification techniques for aquatic organisms has been minimal. In this paper, we focus on advancing …

Negative association between parental care and sibling cooperation in earwigs: a new perspective on the early evolution of family life?

2015

International audience; The evolution of family life requires net fitness benefits for offspring, which are commonly assumed to mainly derive from parental care. However, an additional source of benefits for offspring is often overlooked: cooperative interactions among juvenile siblings. In this study, we examined how sibling cooperation and parental care could jointly contribute to the early evolution of family life. Specifically, we tested whether the level of food transferred among siblings (sibling cooperation) in the European earwig F orficula auricularia (1) depends on the level of maternal food provisioning (parental care) and (2) is translated into offspring survival, as well as fem…

The giant spectrin βV couples the molecular motors to phototransduction and Usher syndrome type I proteins along their trafficking route.

2013

International audience; Mutations in the myosin VIIa gene cause Usher syndrome type IB (USH1B), characterized by deaf-blindness. A delay of opsin trafficking has been observed in the retinal photoreceptor cells of myosin VIIa-deficient mice. We identified spectrin bV, the mammalian b-heavy spectrin, as a myosin VIIa-and rhodopsin-interacting partner in photoreceptor cells. Spectrin bV displays a polarized distribution from the Golgi apparatus to the base of the outer segment, which, unlike that of other b spectrins, matches the trafficking route of opsin and other phototransduction proteins. Formation of spectrin bV-rhodopsin complex could be detected in the differentiating photoreceptors a…

A new late pleistocene vertebrate faunal complex from Sicily (S. Teodoro Cave, North-Eastern Sicily, Italy)

2001

Previous excavations at the S. Teodoro Cave were carried on mainly in the upper unit, Late Glacial in age, containing late Upper Palaeolithic stone artefacts and no endemic mammals remains belonging to the Castello Faunal complex, the youngest of the Pleistocene Sicilian faunal complexes. This unit overlies an older deposit of clay and sands which contain Pleistocene endemic mammal remains. During 1998 excavations a maximum depth of m 1.50 over an area of about 12 sq. m has been exploited. Scarce evidences of the Late Glacial have been encountered during excavations. The investigated lower unit (unit B) is made of clayey sands and gravels containing a highly diversified assemblage of verteb…

The Malawi Rift and vertebrate paleobiogeography of the African Rift Valley

2017

The oldest fossil evidence of a dental lamina in sharks

2006

(2006). The oldest fossil evidence of a dental lamina in sharks. Journal of Vertebrate Paleontology: Vol. 26, No. 4, pp. 1002-1003.