Untitled

Ostroumova, T. V.; Markova, L. N.

doi:10.1023/a:1015066424928

Cited by 6 publications

(2 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The diversity of biogenic amines in animals has been produced by several evolutionarily conserved enzymes (figure 4). Ctenophores [185], sponges [66,[186][187][188][189][190][191], placozoans and cnidarians [192][193][194][195][196][197][198][199][200][201][202][203][204][205][206][207][208][209][210] might synthesize additional catecholamines and indolamines, but their locations and potential transmitter functions should be subject to careful investigations. There are several, mostly early, reports for the presence of serotonin, dopamine and noradrenaline in cnidarians [197,200,[211][212][213][214][215][216][217][218][219][220], but it was not consistent with genomic data about predicted synthetic enzymes [176,177,179].…”

Section: (F ) Biogenic Aminesmentioning

confidence: 99%

Neural versus alternative integrative systems: molecular insights into origins of neurotransmitters

Moroz

Romanova

Kohn

2021

Phil. Trans. R. Soc. B

113

View full text Add to dashboard Cite

Transmitter signalling is the universal chemical language of any nervous system, but little is known about its early evolution. Here, we summarize data about the distribution and functions of neurotransmitter systems in basal metazoans as well as outline hypotheses of their origins. We explore the scenario that neurons arose from genetically different populations of secretory cells capable of volume chemical transmission and integration of behaviours without canonical synapses. The closest representation of this primordial organization is currently found in Placozoa, disk-like animals with the simplest known cell composition but complex behaviours. We propose that injury-related signalling was the evolutionary predecessor for integrative functions of early transmitters such as nitric oxide, ATP, protons, glutamate and small peptides. By contrast, acetylcholine, dopamine, noradrenaline, octopamine, serotonin and histamine were recruited as canonical neurotransmitters relatively later in animal evolution, only in bilaterians. Ligand-gated ion channels often preceded the establishment of novel neurotransmitter systems. Moreover, lineage-specific diversification of neurotransmitter receptors occurred in parallel within Cnidaria and several bilaterian lineages, including acoels. In summary, ancestral diversification of secretory signal molecules provides unique chemical microenvironments for behaviour-driven innovations that pave the way to complex brain functions and elementary cognition. This article is part of the theme issue ‘Basal cognition: multicellularity, neurons and the cognitive lens'.

show abstract

Section: (F ) Biogenic Aminesmentioning

confidence: 99%

Neural versus alternative integrative systems: molecular insights into origins of neurotransmitters

Moroz

Romanova

Kohn

2021

Phil. Trans. R. Soc. B

113

View full text Add to dashboard Cite

show abstract

“…In Hydra attenuata catecholamine inhibitors could prevent regeneration. Dopamine is a specific catecholamine where the inhibition induces morphogenetic anomalies in gastral spheroids, which do not retain their natural organizer 71 . However, when paclitaxel was applied, no morphological anomalies were observed in any of the surviving spheroids in the present study, so this precise mechanism appears not to be important in our case.…”

Section: Microtubule Polymerization Modifying Drugs Reveal Polymerizementioning

confidence: 99%

Symmetry breaking andde-novoaxis formation inhydraspheroids: the microtubule cytoskeleton as a pivotal element

Sander

Pasula

Sander

et al. 2020

Preprint

View full text Add to dashboard Cite

The establishment of polarity in cells and tissues is one of the first steps in multicellular development. The 'eternal embryo' hydra can completely regenerate from a disorganised cell cluster or a small fragment of tissue of about 10, 000 cells. During regeneration, the cells first form a hollow cell spheroid, which then undergoes de-novo symmetry breaking to irreversibly polarise. Here, we address the symmetry-related shape changes. Prior to axis establishment, the spherical aggregates of regenerating cells show highly coordinated mechanical oscillations on several timescales that are isotropic in space. There are transient periods of fluctuations in defined arbitrary directions, until these undergo a clearly identified irreversible transition to directed fluctuations along the future main axis of the regenerating hydra. Stabilised cytosolic actin structures disappear during the de-novo polarisation, while polymerised microtubules remain. Drugs that depolymerise actin filaments accelerate the symmetry breaking process, while drug-stabilised actin filaments prevent it. Nocodazole-depolymerised microtubules prevent symmetry breaking, but it can be rescued by the microtubule-stabilising drug paclitaxel at concentrations where microtubular structures start to reappear. We discuss the possibility that these mechanical fluctuations induce the orientation of the microtubules, which contribute to β -catenin nuclear translocation, to increase the organiserforming-potential of the cells. Our data suggest that in regenerating hydra spheroids, the biomechanical shape fluctuations are an integral part of the cooperative polarisation of the self-organising hydra, during which microtubules play a pivotal role.

show abstract

Neuronal evolution: analysis of regulatory genes in a first-evolved nervous system, the hydra nervous system

2004

View full text Add to dashboard Cite

Cnidarians represent the first animal phylum with an organized nervous system and a complex active behavior. The hydra nervous system is formed of sensory-motoneurons, ganglia neurons and mechanoreceptor cells named nematocytes, which all differentiate from a common stem cell. The neurons are organized as a nerve net and a subset of neurons participate in a more complex structure, the nerve ring that was identified in most cnidarian species at the base of the tentacles. In order to better understand the genetic control of this neuronal network, we analysed the expression of evolutionarily-conserved regulatory genes in the hydra nervous system. The PRD-CLASS homeogene, prdl-b, and the nuclear orphan receptor, hyCOUP-TF, are expressed at strong levels in proliferating nematoblasts, a lineage where they were found repressed during patterning and morphogenesis, and at low levels in distinct subsets of neurons. Interestingly, PRD-CLASS homeobox and COUP-TF genes are also expressed during neurogenesis in bilaterians, suggesting that mechanoreceptor and neuronal cells derive from a common ancestral cell. Moreover, the PRD-CLASS homeobox gene prdl-a, the ANTP-CLASS homeobox gene msh, and the thrombospondin-related gene TSP1, which are expressed in distinct subset of neurons in the adult polyp, are also expressed during early budding and/or head regeneration. These data strengthen the fact that two distinct regulations, one for neurogenesis and another for patterning, already apply to these regulatory genes, a feature also identified in bilaterian related-genes.

show abstract

Untitled

Cited by 6 publications

References 9 publications

Neural versus alternative integrative systems: molecular insights into origins of neurotransmitters

Neural versus alternative integrative systems: molecular insights into origins of neurotransmitters

Symmetry breaking andde-novoaxis formation inhydraspheroids: the microtubule cytoskeleton as a pivotal element

Neuronal evolution: analysis of regulatory genes in a first-evolved nervous system, the hydra nervous system

Contact Info

Product

Resources

About