Nervous systems and scenarios for the invertebrate-to-vertebrate transition

Older evolutionary scenarios for the origin of vertebrates often gave nervous systems top billing in accordance with the notion that a big-brained Homo sapiens crowned a tree of life shaped mainly by progressive evolution. Now, however, tree thinking positions all extant organisms equidistant from the tree's root, and molecular phylogenies indicate that regressive evolution is more common than previously suspected. Even so, contemporary theories of vertebrate origin still focus on the nervous system because of its functional importance, its richness in characters for comparative biology, and its central position in the two currently prominent scenarios for the invertebrate-to-vertebrate transition, which grew out of the markedly neurocentric annelid and enteropneust theories of the nineteenth century. Both these scenarios compare phyla with diverse overall body plans. This diversity, exacerbated by the scarcity of relevant fossil data, makes it challenging to establish plausible homologies between component parts (e.g. nervous system regions). In addition, our current understanding of the relation between genotype and phenotype is too preliminary to permit us to convert gene network data into structural features in any simple way. These issues are discussed here with special reference to the evolution of nervous systems during proposed transitions from invertebrates to vertebrates.

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Myosinome: A Database of Myosins from Select Eukaryotic Genomes to Facilitate Analysis of Sequence-Structure-Function Relationships

Bioinformatics and Biology Insights ◽

10.4137/bbi.s9902 ◽

2012 ◽

Vol 6 ◽

pp. BBI.S9902 ◽

Cited By ~ 3

Author(s):

Divya P. Syamaladevi ◽

Margaret S Sunitha ◽

S. Kalaimathy ◽

Chandrashekar C. Reddy ◽

Mohammed Iftekhar ◽

...

Keyword(s):

Conformational Changes ◽

Atp Hydrolysis ◽

Homo Sapiens ◽

Relevant Literature ◽

Myosin Ii ◽

Coiled Coil ◽

Structural Features ◽

Model Organisms ◽

Congenital Diseases ◽

C Elegans

Myosins are one of the largest protein superfamilies with 24 classes. They have conserved structural features and catalytic domains yet show huge variation at different domains resulting in a variety of functions. Myosins are molecules driving various kinds of cellular processes and motility until the level of organisms. These are ATPases that utilize the chemical energy released by ATP hydrolysis to bring about conformational changes leading to a motor function. Myosins are important as they are involved in almost all cellular activities ranging from cell division to transcriptional regulation. They are crucial due to their involvement in many congenital diseases symptomatized by muscular malfunctions, cardiac diseases, deafness, neural and immunological dysfunction, and so on, many of which lead to death at an early age. We present Myosinome, a database of selected myosin classes (myosin II, V, and VI) from five model organisms. This knowledge base provides the sequences, phylogenetic clustering, domain architectures of myosins and molecular models, structural analyses, and relevant literature of their coiled-coil domains. In the current version of Myosinome, information about 71 myosin sequences belonging to three myosin classes (myosin II, V, and VI) in five model organisms ( Homo Sapiens, Mus musculus, D. melanogaster, C. elegans and S. cereviseae) identified using bioinformatics surveys are presented, and several of them are yet to be functionally characterized. As these proteins are involved in congenital diseases, such a database would be useful in short-listing candidates for gene therapy and drug development. The database can be accessed from http://caps.ncbs.res.in/myosinome .

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Synapsin I (protein I), a nerve terminal-specific phosphoprotein. I. Its general distribution in synapses of the central and peripheral nervous system demonstrated by immunofluorescence in frozen and plastic sections.

The Journal of Cell Biology ◽

10.1083/jcb.96.5.1337 ◽

1983 ◽

Vol 96 (5) ◽

pp. 1337-1354 ◽

Cited By ~ 345

Author(s):

P De Camilli ◽

R Cameron ◽

P Greengard

Keyword(s):

Nervous System ◽

Detailed Examination ◽

Specific Protein ◽

Nerve Cells ◽

General Distribution ◽

Synapsin I ◽

Nervous Systems ◽

Synaptic Region ◽

Specific Localization ◽

Peripheral Nervous Systems

Synapsin I (formerly referred to as protein I) is the collective name for two almost identical phosphoproteins, synapsin Ia and synapsin Ib (protein Ia and protein Ib), present in the nervous system. Synapsin I has previously been shown by immunoperoxidase studies (De Camilli, P., T. Ueda, F. E. Bloom, E. Battenberg, and P. Greengard, 1979, Proc. Natl. Acad. Sci. USA, 76:5977-5981; Bloom, F. E., T. Ueda, E. Battenberg, and P. Greengard, 1979, Proc. Natl. Acad. Sci. USA 76:5982-5986) to be a neuron-specific protein, present in both the central and peripheral nervous systems and concentrated in the synaptic region of nerve cells. In those preliminary studies, the occurrence of synapsin I could be demonstrated in only a portion of synapses. We have now carried out a detailed examination of the distribution of synapsin I immunoreactivity in the central and peripheral nervous systems. In this study we have attempted to maximize the level of resolution of immunohistochemical light microscopy images in order to estimate the proportion of immunoreactive synapses and to establish their precise distribution. Optimal results were obtained by the use of immunofluorescence in semithin sections (approximately 1 micron) prepared from Epon-embedded nonosmicated tissues after the Epon had been removed. Our results confirm the previous observations on the specific localization of synapsin I in nerve cells and synapses. In addition, the results strongly suggest that, with a few possible exceptions involving highly specialized neurons, all synapses contain synapsin I. Finally, immunocytochemical experiments indicate that synapsin I appearance in the various regions of the developing nervous system correlates topographically and temporally with the appearance of synapses. In two accompanying papers (De Camilli, P., S. M. Harris, Jr., W. B. Huttner, and P. Greengard, and Huttner, W. B., W. Schiebler, P. Greengard, and P. De Camilli, 1983, J. Cell Biol. 96:1355-1373 and 1374-1388, respectively), evidence is presented that synapsin I is specifically associated with synaptic vesicles in nerve endings.

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Analysis of functional importance of binding sites in the Drosophila gap gene network model

BMC Genomics ◽

10.1186/1471-2164-16-s13-s7 ◽

2015 ◽

Vol 16 (Suppl 13) ◽

pp. S7 ◽

Cited By ~ 4

Author(s):

Konstantin Kozlov ◽

Vitaly V Gursky ◽

Ivan V Kulakovskiy ◽

Arina Dymova ◽

Maria Samsonova

Keyword(s):

Network Model ◽

Binding Sites ◽

Gene Network ◽

Functional Importance ◽

Gap Gene

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Drosophila Stathmin: A Microtubule-destabilizing Factor Involved in Nervous System Formation

Molecular Biology of the Cell ◽

10.1091/mbc.01-07-0362 ◽

2002 ◽

Vol 13 (2) ◽

pp. 698-710 ◽

Cited By ~ 56

Author(s):

Sylvie Ozon ◽

Antoine Guichet ◽

Olivier Gavet ◽

Siegfried Roth ◽

André Sobel

Keyword(s):

Nervous System ◽

System Development ◽

Nervous System Development ◽

Microtubule Assembly ◽

Nervous Systems ◽

Germ Cell Migration ◽

Numerous Cell ◽

First Time

Stathmin is a ubiquitous regulatory phosphoprotein, the generic element of a family of neural phosphoproteins in vertebrates that possess the capacity to bind tubulin and interfere with microtubule dynamics. Although stathmin and the other proteins of the family have been associated with numerous cell regulations, their biological roles remain elusive, as in particular inactivation of the stathmin gene in the mouse resulted in no clear deleterious phenotype. We identified stathmin phosphoproteins inDrosophila, encoded by a unique gene sharing the intron/exon structure of the vertebrate stathmin andstathmin family genes. They interfere with microtubule assembly in vitro, and in vivo when expressed in HeLa cells. Drosophila stathmin expression is regulated during embryogenesis: it is high in the migrating germ cells and in the central and peripheral nervous systems, a pattern resembling that of mammalian stathmin. Furthermore, RNA interference inactivation ofDrosophila stathmin expression resulted in germ cell migration arrest at stage 14. It also induced important anomalies in nervous system development, such as loss of commissures and longitudinal connectives in the ventral cord, or abnormal chordotonal neuron organization. In conclusion, a single Drosophilagene encodes phosphoproteins homologous to the entire vertebrate stathmin family. We demonstrate for the first time their direct involvement in major biological processes such as development of the reproductive and nervous systems.

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Glial kon/NG2 gene network for central nervous system repair

Neural Regeneration Research ◽

10.4103/1673-5374.198969 ◽

2017 ◽

Vol 12 (1) ◽

pp. 31 ◽

Cited By ~ 2

Author(s):

Alicia Hidalgo ◽

Maria Losada-Perez ◽

Neale Harrison

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Gene Network ◽

Central Nervous System Repair

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Network Neuroscience and Personality

Personality Neuroscience ◽

10.1017/pen.2018.12 ◽

2018 ◽

Vol 1 ◽

Cited By ~ 13

Author(s):

Sebastian Markett ◽

Christian Montag ◽

Martin Reuter

Keyword(s):

Nervous System ◽

Individual Differences ◽

Personality Traits ◽

Brain Connectivity ◽

Gray Matter Volume ◽

Actual Behavior ◽

Present Contribution ◽

Nervous Systems ◽

The Brain ◽

Network Neuroscience

AbstractPersonality and individual differences originate from the brain. Despite major advances in the affective and cognitive neurosciences, however, it is still not well understood how personality and single personality traits are represented within the brain. Most research on brain-personality correlates has focused either on morphological aspects of the brain such as increases or decreases in local gray matter volume, or has investigated how personality traits can account for individual differences in activation differences in various tasks. Here, we propose that personality neuroscience can be advanced by adding a network perspective on brain structure and function, an endeavor that we label personality network neuroscience.With the rise of resting-state functional magnetic resonance imaging (MRI), the establishment of connectomics as a theoretical framework for structural and functional connectivity modeling, and recent advancements in the application of mathematical graph theory to brain connectivity data, several new tools and techniques are readily available to be applied in personality neuroscience. The present contribution introduces these concepts, reviews recent progress in their application to the study of individual differences, and explores their potential to advance our understanding of the neural implementation of personality.Trait theorists have long argued that personality traits are biophysical entities that are not mere abstractions of and metaphors for human behavior. Traits are thought to actually exist in the brain, presumably in the form of conceptual nervous systems. A conceptual nervous system refers to the attempt to describe parts of the central nervous system in functional terms with relevance to psychology and behavior. We contend that personality network neuroscience can characterize these conceptual nervous systems on a functional and anatomical level and has the potential do link dispositional neural correlates to actual behavior.

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The Last Threshold

Inference: International Review of Science ◽

10.37282/991819.17.3 ◽

2017 ◽

Vol 3 (1) ◽

Author(s):

Anne Dambricourt Malassé

Keyword(s):

Nervous System ◽

Homo Sapiens ◽

Threshold Effects ◽

Definition Of ◽

Base Of The Skull

Anne Dambricourt Malassé argues for a morphological definition of Homo sapiens that allows us to see humans evolving through the straightening of the base of the skull, a result of the growing complexity of the nervous system, which led to a succession of threshold effects.

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The Problem

Brains as Engines of Association ◽

10.1093/oso/9780190880163.003.0005 ◽

2019 ◽

pp. 48-58

Author(s):

Dale Purves

Keyword(s):

Nervous System ◽

Real World ◽

Physical World ◽

Sensory Systems ◽

Fundamental Question ◽

Physical Parameters ◽

Everyday Experience ◽

Nervous Systems ◽

Neural Connections ◽

Sensory Inputs

Although understanding neural functions has progressed at a remarkable pace in recent decades, a fundamental question remains: How does the nervous system relate the objective world to the subjective domain of perception? Everyday experience implies that the neural connections on which we and other animals depend link physical parameters in the environment with useful responses. But that interpretation won't work: biological sensory systems cannot measure the physical world. Whereas something is linking sensory inputs to useful responses, it is not the physical world that instruments measure. How, then, have we animals met this challenge, and what is it that we end up perceiving? The purpose of this chapter is to suggest how nervous systems have evolved to deal with the inability to convey the objective properties of the real world.

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Organisms With Nervous Systems

Brains as Engines of Association ◽

10.1093/oso/9780190880163.003.0003 ◽

2019 ◽

pp. 23-34

Author(s):

Dale Purves

Keyword(s):

Nervous System ◽

Operating Principle ◽

The Other ◽

Neural Systems ◽

Animal Kingdom ◽

Nervous Systems ◽

Life On Earth

Definitions of the term “animals” in dictionaries and textbooks are surprisingly vague. The characteristics usually mentioned are eukaryotic, multicellular, heterotrophic, sexually reproducing, and capable of rapid and independent movement. But some or all of these properties are characteristic of many organisms in the other kingdoms of life on Earth. In fact, the major distinguishing feature of animals in most cases is the presence of a nervous system. But if nervous systems are indeed one of the main attributes that distinguish organisms in the animal kingdom, what exactly are nervous systems and what advantages do they bring? Without at least some provisional answers, seeking the operating principle of neural systems would be futile.

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The Retromolar Space and Wisdom Teeth in Humans: Reasons for Surgical Tooth Extraction

European Journal of Dentistry ◽

10.1055/s-0040-1716312 ◽

2020 ◽

Author(s):

Abed El Kaseh ◽

Maher Al Shayeb ◽

Syed Kuduruthullah ◽

Nadeem Gulrez

Keyword(s):

Homo Sapiens ◽

Third Molar ◽

Structural Features ◽

Morphometric Study ◽

Third Molars ◽

Facial Skeleton ◽

Lower Jaw ◽

Wisdom Teeth ◽

Retromolar Region

Abstract Objective This article explores the problem of developing pathologies in the retromolar region. Findings can serve a framework for disease prevention and for the improvement of the quality of life of patients. The present study aims to justify the possibility of utilizing morphometric methods to foresee problems in the eruption of third molars. Materials and Methods A comprehensive morphometric study of the lower jaw and facial skeleton involves 100 skulls of Homo sapiens to identify the anatomical causes of problems with wisdom teeth eruption. All said skulls are divided in two groups: I: skulls with intact dentition; II: skulls with impacted third molars. Results This work allows detecting abnormalities in the eruption of the third molar with high probability of success. The abnormalities in point are considered not only those associated with the generally accepted parameters but also those that occur in the leptoprosopic face cases. Conclusions Face type and the structural features of the facial skeleton play a significant role in the abnormal eruption of the lower third molar.

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