A new look at the architecture and dynamics of theHydranerve net DOI Creative Commons
Athina Keramidioti,

Sandra Schneid,

Christina Busse

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Feb. 22, 2023

Abstract The Hydra nervous system is the paradigm of a “simple nerve net”. Nerve cells in , as many cnidarian polyps, are organized net extending throughout body column. This required for control spontaneous behavior: elimination leads to polyps that do not move and incapable capturing ingesting prey (Campbell, 1976). We have re-examined structure by immunostaining fixed with novel antibody stains all . Confocal imaging shows there two distinct nets, one ectoderm endoderm, unexpected absence endoderm tentacles. nets contact each other. High-resolution TEM serial block face SEM show consist bundles parallel overlapping neurites. Results from transgenic lines neurite include different neural circuits hence neurites require circuit-specific recognition. cell-specific innexins indicate gap junctions can provide this specificity. occurrence supports model continuous growth differentiation lateral addition new existing net. was confirmed tracking newly differentiated cells.

Language: Английский

Topological structures and syntenic conservation in sea anemone genomes DOI Creative Commons
Bob Zimmermann, Juan D. Montenegro, Sofia Robb

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Dec. 13, 2023

Abstract There is currently little information about the evolution of gene clusters, genome architectures and karyotypes in early branching animals. Slowly evolving anthozoan cnidarians can be particularly informative these features. Here we report chromosome-level assemblies two related anthozoans, sea anemones Nematostella vectensis Scolanthus callimorphus . We find a robust set 15 chromosomes with clear one-to-one correspondence between species. Both genomes show chromosomal conservation, allowing us to reconstruct ancestral cnidarian metazoan blocks, consisting at least 19 16 linkage groups, respectively. that, contrast Bilateria, Hox NK clusters investigated are largely disintegrated, despite presence staggered hox/gbx expression This loss microsynteny conservation may facilitated by shorter distances cis-regulatory sequences their cognate transcriptional start sites. no evidence for topologically associated domains, suggesting fundamental differences long-range regulation compared vertebrates. These data suggest that large sets genes have been retained groups some extant lineages; yet, higher order 3D architecture evolved only after cnidarian-bilaterian split.

Language: Английский

Citations

33

Novel technologies uncover novel ‘anti’-microbial peptides in Hydra shaping the species-specific microbiome DOI Creative Commons
Alexander Klimovich, Thomas C. G. Bosch

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 379(1901)

Published: March 18, 2024

The freshwater polyp Hydra uses an elaborate innate immune machinery to maintain its specific microbiome. Major components of this toolkit are conserved Toll-like receptor (TLR)-mediated pathways and species-specific antimicrobial peptides (AMPs). Our study harnesses advanced technologies, such as high-throughput sequencing machine learning, uncover a high complexity the 's AMPs repertoire. Functional analysis reveals that these against diverse members microbiome expressed in spatially controlled pattern. Notably, outer epithelial layer, produced mainly neurons. neuron-derived secreted directly into glycocalyx, habitat for symbiotic bacteria, display selectivity spatial restriction expression. In endodermal contrast, cells produce abundance different including arminin hydramacin families, while gland secrete kazal-type protease inhibitors. Since layer lines gastric cavity devoid we assume endodermally protect from intruding pathogens. conclusion, employs complex set distinct tissue layers cell types combat pathogens stable organized This article is part theme issue ‘Sculpting microbiome: how host factors determine respond microbial colonization’.

Language: Английский

Citations

12

Nutrition-induced changes in the microbiota can cause dysbiosis and disease development DOI Creative Commons
Tim Lachnit, Laura Ulrich,

Fiete M. Willmer

et al.

mBio, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

Eukaryotic organisms are associated with complex microbial communities. Changes within these communities have been implicated in disease development. Nonetheless, it remains unclear whether changes a cause or consequence of disease. Here, we report causal link between environment-induced shifts the microbiota and Using model organism Hydra, observed composition when transferring laboratory-grown Hydra to natural lake environments. These were caused not only by new colonizers, through process community coalescence (merging previously separate communities), but also water nutrients. Moreover, selective manipulation nutrient environment induced compound-specific followed Finally, L-arginine supplementation alone transition Pseudomonas from symbiotic pathogenic, leading an upregulation immune response genes, tissue degradation, host death. findings challenge notion that host-associated is exclusively controlled host, highlighting dynamic interplay epithelial environment, colonizer pool, conditions surrounding water. Furthermore, our results show overfeeding allows for uncontrolled growth versatile interactions host. Environmental may thus render symbionts potential hazard their hosts, blurring divide pathogenic non-pathogenic microbes.IMPORTANCEThis study highlights critical need understand environmental factors obtain holistic view on organismal health. Our demonstrate ecosystem-wide trafficking (community coalescence) reshape profound implications By exploring nutrient-driven composition, research finds experimental support "overfeeding hypothesis," which states alters functionality such overabundance nutrients can facilitate development, transforming microbes into pathogens. emphasize role metabolic driving pathogenicity. provides empirical evidence "pathogenic potential" concept, challenging traditional distinctions supporting idea any microbe become under certain conditions.

Language: Английский

Citations

1

The Hydra stem cell system – Revisited DOI Creative Commons
Thomas W. Holstein

Cells and Development, Journal Year: 2023, Volume and Issue: 174, P. 203846 - 203846

Published: April 28, 2023

Cnidarians are >600 million years old and considered the sister group of Bilateria based on numerous molecular phylogenetic studies. Apart from Hydra, genomes all major clades Cnidaria have been uncovered (e.g. Aurelia, Clytia, Nematostella Acropora) they reveal a remarkable completeness metazoan genomic toolbox. Of particular interest is model system aging research, regenerative biology, stem cell biology. With knowledge gained scRNA it now possible to characterize expression profiles types with great precision. In functional studies, our picture Hydra biology has changed, we in process obtaining clear homeostasis properties different populations. Even though often compared plant systems, new data germline regeneration, but also dynamics plasticity nervous system, show that its simple body plan represents nutshell prototype an animal lineages, whose correspond many ways Bilateria. This review provides overview four two epithelial lineages constitute ectoderm endoderm, as well multipotent somatic interstitial lineage (MPSC) (GSC), known cells Hydra.

Language: Английский

Citations

20

A new look at the architecture and dynamics of the Hydra nerve net DOI Creative Commons
Athina Keramidioti,

Sandra Schneid,

Christina Busse

et al.

eLife, Journal Year: 2024, Volume and Issue: 12

Published: Feb. 26, 2024

The Hydra nervous system is the paradigm of a ‘simple nerve net’. Nerve cells in , as many cnidarian polyps, are organized net extending throughout body column. This required for control spontaneous behavior: elimination leads to polyps that do not move and incapable capturing ingesting prey (Campbell, 1976). We have re-examined structure by immunostaining fixed with novel antibody stains all . Confocal imaging shows there two distinct nets, one ectoderm endoderm, unexpected absence endoderm tentacles. nets contact each other. High-resolution TEM (transmission electron microscopy) serial block face SEM (scanning show consist bundles parallel overlapping neurites. Results from transgenic lines neurite include different neural circuits hence neurites require circuit-specific recognition. cell-specific innexins indicate gap junctions can provide this specificity. occurrence supports model continuous growth differentiation lateral addition new existing net. was confirmed tracking newly differentiated cells.

Language: Английский

Citations

8

Differentiation trajectories of theHydranervous system reveal transcriptional regulators of neuronal fate DOI Creative Commons
Abby S. Primack, Jack F. Cazet, Hannah Morris Little

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: March 16, 2023

The small freshwater cnidarian polyp

Language: Английский

Citations

14

Satiety controls behavior in Hydra through an interplay of pre-enteric and central nervous system-like neuron populations DOI Creative Commons
Christoph Giez, Christopher Noack,

Ehsan Sakib

et al.

Cell Reports, Journal Year: 2024, Volume and Issue: 43(6), P. 114210 - 114210

Published: May 23, 2024

Hunger and satiety can have an influence on decision-making, sensory processing, motor behavior by altering the internal state of brain. This process necessitates integration peripheral stimuli into central nervous system. Here, we show how animals without a system such as cnidarian Hydra measure integrate neuronal circuits which specific populations are involved. We demonstrate that this simple system, previously referred to diffuse, has endodermal subpopulation (N4) similar enteric (feeding-associated behavior) ectodermal population (N3) performs system-like functions (physiology/motor). view supposedly could open important window origin more complex systems.

Language: Английский

Citations

6

Multiple neuronal populations control the eating behavior in Hydra and are responsive to microbial signals DOI Creative Commons
Christoph Giez,

Denis Pinkle,

Yan Giencke

et al.

Current Biology, Journal Year: 2023, Volume and Issue: 33(24), P. 5288 - 5303.e6

Published: Nov. 22, 2023

Although recent studies indicate the impact of microbes on central nervous systems and behavior, it remains unclear how relationship between functionality system, microbiota evolved. In this work, we analyzed eating behavior Hydra, a host that has simple system low-complexity microbiota. To identify neuronal subpopulations involved, used subpopulation-specific cell ablation calcium imaging. The role was uncovered by manipulating diversity natural We show different are functioning together to control behavior. Animals with drastically reduced microbiome had severe difficulties in mouth opening due significantly increased level glutamate. This could be reversed adding full complement summary, provide mechanistic explanation Hydra's controls what play this.

Language: Английский

Citations

12

The dynamic genomes of Hydra and the anciently active repeat complement of animal chromosomes DOI Open Access
Koto Kon‐Nanjo, Tetsuo Kon, Tracy Chih-Ting Koubkova Yu

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: March 14, 2024

Many animal genomes are characterized by highly conserved chromosomal homologies that pre-date the ancient origin of this clade. Despite such conservation, evolutionary forces behind retention, expansion, and contraction elements, resulting macro-evolutionary implications, unknown. Here we present a comprehensive stem-cell resolved genomic transcriptomic study fresh-water cnidarian Hydra, an its high regenerative capacity, ability to propagate clonally, apparent lack aging. Using single-haplotype telomere-to-telomere genome assemblies two recently diverged hydra strains, show how history elements is shaped both old recent transposable element (TE) expansions. Unique features biology allowed us compare individual hydra's three stem cell lineages. We distinct TE families active at transcriptional levels via non-random insertions in each these In transcriptomes, over 14,000 transcripts were composed nearly complete sequences, further classification into families, subfamilies, loci reveals type-specific expression. The TEs include differentially contribute changes size as well persistent structural variants around associated with proliferation. Our 14 primarily act role predominantly DNA elements. Evolutionary analysis revealed constitute core eukaryotic metazoan genomes. results suggest for self-renewing components persist beyond homologies.

Language: Английский

Citations

4

Chromosome-level genome assembly of Hydractinia symbiolongicarpus DOI Creative Commons
Koto Kon‐Nanjo, Tetsuo Kon, Helen R Horkan

et al.

G3 Genes Genomes Genetics, Journal Year: 2023, Volume and Issue: unknown

Published: May 18, 2023

Abstract Hydractinia symbiolongicarpus is a pioneering model organism for stem cell biology, being one of only few animals with adult pluripotent cells (known as i-cells). However, the unavailability chromosome-level genome assembly has hindered comprehensive understanding global gene regulatory mechanisms underlying function and evolution i-cells. Here, we report first H. (HSymV2.0) using PacBio HiFi long-read sequencing Hi-C scaffolding. The final 483 Mb in total length 15 chromosomes representing 99.8% assembly. Repetitive sequences were found to account 296 (61%) genome; provide evidence at least two periods repeat expansion past. A 25,825 protein-coding genes predicted this assembly, which include 93.1% metazoan Benchmarking Universal Single-Copy Orthologs (BUSCO) set. 92.8% (23,971 genes) proteins functionally annotated. showed high degree macrosynteny conservation Hydra vulgaris genome. This will be an invaluable resource research community that enhances broad biological studies on unique organism.

Language: Английский

Citations

10