scholarly journals Non-thalamic origin of zebrafish sensory nuclei implies convergent evolution of visual pathways in amniotes and teleosts

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Solal Bloch ◽  
Hanako Hagio ◽  
Manon Thomas ◽  
Aurélie Heuzé ◽  
Jean-Michel Hermel ◽  
...  
Keyword(s):  
Convergent Evolution ◽  
Cell Lineage ◽  
Projection Neurons ◽  
Vertebrate Species ◽  
Thalamic Nuclei ◽  
Sensory Structure ◽  
Wide Range ◽  
Visual Projection ◽  
Juvenile Stages ◽  
Lateral Nucleus

Ascending visual projections similar to the mammalian thalamocortical pathway are found in a wide range of vertebrate species, but their homology is debated. To get better insights into their evolutionary origin, we examined the developmental origin of a thalamic-like sensory structure of teleosts, the preglomerular complex (PG), focusing on the visual projection neurons. Similarly to the tectofugal thalamic nuclei in amniotes, the lateral nucleus of PG receives tectal information and projects to the pallium. However, our cell lineage study in zebrafish reveals that the majority of PG cells are derived from the midbrain, unlike the amniote thalamus. We also demonstrate that the PG projection neurons develop gradually until late juvenile stages. Our data suggest that teleost PG, as a whole, is not homologous to the amniote thalamus. Thus, the thalamocortical-like projections evolved from a non-forebrain cell population, which indicates a surprising degree of variation in the vertebrate sensory systems.

scholarly journals Non-thalamic origin of zebrafish sensory relay nucleus: convergent evolution of visual pathways in amniotes and teleosts

2020 ◽  
Author(s):  
Solal Bloch ◽  
Hanako Hagio ◽  
Manon Thomas ◽  
Aurélie Heuzé ◽  
Jean-Michel Hermel ◽  
...  
Keyword(s):  
Convergent Evolution ◽  
Cell Lineage ◽  
Juvenile Stage ◽  
Projection Neurons ◽  
Lateral Part ◽  
Vertebrate Species ◽  
Thalamic Nuclei ◽  
Sensory Pathways ◽  
Wide Range ◽  
Relay Nucleus

AbstractAscending visual projections similar to the mammalian thalamocortical pathway are found in a wide range of vertebrate species, but their homologous relationship is debated. To get better insights into their evolutionary origin, we examined the developmental origin of a visual relay nucleus in zebrafish (a teleost fish). Similarly to the tectofugal visual thalamic nuclei in amniotes, the lateral part of the preglomerular complex (PG) in teleosts receives tectal information and projects to the pallium. However, our cell lineage study reveals that the majority of PG cells are derived from the midbrain, not from the forebrain. We also demonstrate that the PG projection neurons develop gradually until juvenile stage, unlike the thalamic projection neurons. Our data suggest that teleost PG is not homologous to the amniote thalamus and that thalamocortical-like projections can evolve from a non-forebrain cell population. Thus, sensory pathways in vertebrate brains exhibit a surprising degree of variation.

NMDAR-1 staining in the lateral geniculate nucleus of normal and visually deprived cats

2000 ◽  
Vol 17 (2) ◽  
pp. 187-196 ◽  
Author(s):  
JOKUBAS ZIBURKUS ◽  
MARTHA E. BICKFORD ◽  
WILLIAM GUIDO
Keyword(s):  
Nmda Receptors ◽  
Lateral Geniculate Nucleus ◽  
Cell Labeling ◽  
Acid Decarboxylase ◽  
Thalamic Nuclei ◽  
Neurofilament Protein ◽  
Lateral Geniculate ◽  
Wide Range ◽  
Soma Size ◽  
Adult Cats

In normal adult cats, a monoclonal antibody directed toward the NR-1 subunit of the N-methyl-d-aspartate (NMDA) receptor (Pharmingen, clone 54.1) produced dense cellular and neuropil labeling throughout all layers of the lateral geniculate nucleus (LGN) and adjacent thalamic nuclei, including the thalamic reticular, perigeniculate, medial intralaminar, and ventral lateral geniculate nuclei. Cellular staining revealed well-defined somata, and in some cases proximal dendrites. NMDAR-1 cell labeling was also evident in the LGN of early postnatal kittens, suggesting that developing LGN cells possess this receptor subunit at or before eye opening. Within the A-layers of the adult LGN, staining encompassed a wide range of soma sizes. Soma size comparisons of NMDAR-1 stained cells with those stained with an antibody directed toward a nonphosphorylated neurofilament protein (SMI-32), which selectively stains Y-relay cells (Bickford et al., 1998), or an antibody to glutamic acid decarboxylase (GAD), which stains for GABAergic interneurons, suggested that NMDA receptors are utilized by relay cells and interneurons. NMDAR-1 staining was also observed in the LGN of cats with early monocular lid suture. Although labeling was apparent in both deprived and nondeprived A-layers of LGN, the distribution of soma sizes was significantly different. In the deprived A-layers of LGN, staining was limited to small- and medium-sized cells. Cells with relatively large soma were lacking. However, cell density measurements as well as soma size comparisons with cells stained for Nissl substance suggested these differences were due to deprivation-induced cell shrinkage and not to a loss of NMDAR-1 staining in Y-cells. Taken together, these results suggest that NMDA receptors are utilized by both relay cells and interneurons in LGN and that alterations in early visual experience do not necessarily affect the expression of NMDA receptors in the LGN.

Postnatal Development of Electrophysiological Properties of Nucleus Accumbens Neurons

2000 ◽  
Vol 84 (5) ◽  
pp. 2204-2216 ◽  
Author(s):  
Marc L. Belleau ◽  
Richard A. Warren
Keyword(s):  
Nucleus Accumbens ◽  
Postnatal Development ◽  
Action Potentials ◽  
Membrane Resistance ◽  
Inward Rectification ◽  
Resting Membrane Potential ◽  
Projection Neurons ◽  
Patch Clamp Technique ◽  
Whole Cell ◽  
Wide Range

We have studied the postnatal development of the physiological characteristics of nucleus accumbens (nAcb) neurons in slices from postnatal day 1 ( P1) to P49 rats using the whole cell patch-clamp technique. The majority of neurons (102/108) were physiologically identified as medium spiny (MS) projection neurons, and only these were subjected to detailed analysis. The remaining neurons displayed characteristics suggesting that they were not MS neurons. Around the time of birth and during the first postnatal weeks, the membrane and firing characteristics of MS neurons were quite different from those observed later. These characteristics changed rapidly during the first 3 postnatal weeks, at which point they began to resemble those found in adults. Both whole cell membrane resistance and membrane time constant decreased more than fourfold during the period studied. The resting membrane potential (RMP) also changed significantly from an average of −50 mV around birth to less than −80 mV by the end of the third postnatal week. During the first postnatal week, the current-voltage relationship of all encountered MS neurons was linear over a wide range of membrane potentials above and below RMP. Through the second postnatal week, the proportion of neurons displaying inward rectification in the hyperpolarized range increased steadily and after P15, all recorded MS neurons displayed significant inward rectification. At all ages, inward rectification was blocked by extracellular cesium and tetra-ethyl ammonium and was not changed by 4-aminopyridine; this shows that inward rectification was mediated by the same currents in young and mature MS neurons. MS neurons fired single and repetitive Na+/K+ action potentials as early as P1. Spike threshold and amplitude remained constant throughout development in contrast to spike duration, which decreased significantly over the same period. Depolarizing current pulses from rest showed that immature MS neurons fired action potentials more easily than their older counterparts. Taken together, the results from the present study suggest that young and adult nAcb MS neurons integrate excitatory synaptic inputs differently because of differences in their membrane and firing properties. These findings provide important insights into signal processing within nAcb during this critical period of development.

scholarly journals Author response: Visual projection neurons in the Drosophila lobula link feature detection to distinct behavioral programs

2016 ◽  
Author(s):  
Ming Wu ◽  
Aljoscha Nern ◽  
W Ryan Williamson ◽  
Mai M Morimoto ◽  
Michael B Reiser ◽  
...  
Keyword(s):  
Feature Detection ◽  
Author Response ◽  
Projection Neurons ◽  
Visual Projection

scholarly journals Myosin MyTH4-FERM structures highlight important principles of convergent evolution

2016 ◽  
Vol 113 (21) ◽  
pp. E2906-E2915 ◽  
Author(s):  
Vicente José Planelles-Herrero ◽  
Florian Blanc ◽  
Serena Sirigu ◽  
Helena Sirkia ◽  
Jeffrey Clause ◽  
...  
Keyword(s):  
Binding Sites ◽  
Convergent Evolution ◽  
Tail Domain ◽  
The Core ◽  
Binding Partners ◽  
The Social ◽  
Wide Range ◽  
Membrane Protrusions ◽  
Characteristic Features ◽  
Multifunctional Platform

Myosins containing MyTH4-FERM (myosin tail homology 4-band 4.1, ezrin, radixin, moesin, or MF) domains in their tails are found in a wide range of phylogenetically divergent organisms, such as humans and the social amoeba Dictyostelium (Dd). Interestingly, evolutionarily distant MF myosins have similar roles in the extension of actin-filled membrane protrusions such as filopodia and bind to microtubules (MT), suggesting that the core functions of these MF myosins have been highly conserved over evolution. The structures of two DdMyo7 signature MF domains have been determined and comparison with mammalian MF structures reveals that characteristic features of MF domains are conserved. However, across millions of years of evolution conserved class-specific insertions are seen to alter the surfaces and the orientation of subdomains with respect to each other, likely resulting in new sites for binding partners. The MyTH4 domains of Myo10 and DdMyo7 bind to MT with micromolar affinity but, surprisingly, their MT binding sites are on opposite surfaces of the MyTH4 domain. The structural analysis in combination with comparison of diverse MF myosin sequences provides evidence that myosin tail domain features can be maintained without strict conservation of motifs. The results illustrate how tuning of existing features can give rise to new structures while preserving the general properties necessary for myosin tails. Thus, tinkering with the MF domain enables it to serve as a multifunctional platform for cooperative recruitment of various partners, allowing common properties such as autoinhibition of the motor and microtubule binding to arise through convergent evolution.

Evolution of Placental Function in Mammals: The Molecular Basis of Gas and Nutrient Transfer, Hormone Secretion, and Immune Responses

2012 ◽  
Vol 92 (4) ◽  
pp. 1543-1576 ◽  
Author(s):  
Anthony M. Carter
Keyword(s):  
Gene Duplication ◽  
Convergent Evolution ◽  
Globin Gene ◽  
Hormone Secretion ◽  
Human Leukocyte ◽  
Amino Acid Transporters ◽  
Placental Lactogens ◽  
Wide Range ◽  
Duplication Events ◽  
Range Of Functions

Placenta has a wide range of functions. Some are supported by novel genes that have evolved following gene duplication events while others require acquisition of gene expression by the trophoblast. Although not expressed in the placenta, high-affinity fetal hemoglobins play a key role in placental gas exchange. They evolved following duplications within the beta-globin gene family with convergent evolution occurring in ruminants and primates. In primates there was also an interesting rearrangement of a cassette of genes in relation to an upstream locus control region. Substrate transfer from mother to fetus is maintained by expression of classic sugar and amino acid transporters at the trophoblast microvillous and basal membranes. In contrast, placental peptide hormones have arisen largely by gene duplication, yielding for example chorionic gonadotropins from the luteinizing hormone gene and placental lactogens from the growth hormone and prolactin genes. There has been a remarkable degree of convergent evolution with placental lactogens emerging separately in the ruminant, rodent, and primate lineages and chorionic gonadotropins evolving separately in equids and higher primates. Finally, coevolution in the primate lineage of killer immunoglobulin-like receptors and human leukocyte antigens can be linked to the deep invasion of the uterus by trophoblast that is a characteristic feature of human placentation.

Projection neurons of the lateral amygdaloid nucleus are virtually silent throughout the sleep--waking cycle

1996 ◽  
Vol 75 (3) ◽  
pp. 1301-1305 ◽  
Author(s):  
H. Gaudreau ◽  
D. Pare
Keyword(s):  
Firing Rate ◽  
Slow Wave Sleep ◽  
Paradoxical Sleep ◽  
Discharge Rate ◽  
Projection Neurons ◽  
Amygdaloid Nucleus ◽  
Average Firing Rate ◽  
Sensory Stimuli ◽  
Firing Rates ◽  
Lateral Nucleus

1. Amygdala neurons were recorded extracellularly during the sleep-waking cycle in chronically implanted cats. Neurons were identified as projection cells when they could be antidromically invaded from the perirhinal and/or entorhinal cortices. 2. In contrast with other nuclei of the amygdala, few spontaneously active neurons were encountered in the lateral nucleus. However, when hunting stimuli were applied to the parahippocampal cortices, we noticed the presence of numerous projection cells that would have otherwise remained undetected because they had little or no spontaneous activity. 3. In the states of waking, slow-wave sleep, and paradoxical sleep, the discharge rate of antidromically invaded neurons averaged 0.09 +/- 0.07 Hz (mean +/- SE) with 82% of cells firing at < 0.01 Hz in all states. However, they transiently increased their firing rate when cats were presented complex sensory stimuli, which apparently were specific to each cell. In contrast to projection cells, spontaneously active neurons of the lateral nucleus that could not be backfired from the parahippocampal cortices had an average firing rate of 4.34 +/- 1.15 Hz with 38% of cells firing at > or = 6 Hz in at least one state. 4. These results on the extremely low firing rates of identified projection cells suggest that previous extracellular studies of lateral amygdaloid neurons were biased toward a class of spontaneously active cells which probably includes local-circuit cells.

Comparison of Oculomotor Neuronal Activity in Paralaminar and Mediodorsal Thalamus in the Rhesus Monkey

2005 ◽  
Vol 93 (1) ◽  
pp. 614-619 ◽  
Author(s):  
Ikuo Tanibuchi ◽  
Patricia S. Goldman-Rakic
Keyword(s):  
Thalamic Nucleus ◽  
Delayed Response ◽  
Thalamic Nuclei ◽  
Related Activity ◽  
Dorsal Thalamus ◽  
Mediodorsal Thalamic Nucleus ◽  
Picture Stimuli ◽  
Fixation Task ◽  
Response Task ◽  
Lateral Nucleus

We previously reported that neurons in the mediodorsal thalamic nucleus (MD) are topographically organized and express spatial and nonspatial coding properties similar to those of the prefrontal areas with which they are connected. In the course of mapping the dorsal thalamus, we also studied neurons in a subset of thalamic nuclei (the caudal part of the ventral lateral nucleus (VLc), the oral part of the ventral posterior lateral nucleus (VPLo), the parvocellular part of the ventral anterior nucleus (VApc)) lateral to the MD and just across the internal medullary lamina. We compared these “paralaminar” neurons to MD neurons by having monkeys perform the same spatial and nonspatial cognitive tasks as those used to investigate the MD; these included two saccadic tasks—one requiring delayed and the other immediate responses—and one picture fixation task. Of the paralaminar thalamic neurons modulated by the saccadic tasks, a majority had saccade-related activity, and this was nearly always spatially tuned. Also, for about half of these neurons, the saccade-related activity occurred exclusively during the delayed-response task. No neurons with event-related activity in the saccadic tasks were preferentially modulated by specific picture stimuli, although other neurons were. All of these results were similar to what we had found for MD neurons. However, in contrast to the high proportion of presaccadic responses observed in the MD, the majority of saccade-related neurons in paralaminar thalamus exhibited mid- or postsaccadic activity, i.e., that started during or after the saccade. Our findings suggest that neurons in the paralaminar thalamus may be possible conduits of oculomotor feedback signals, especially during memory-guided saccades.

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