Developmental Biology: Reissner’s Fiber and Straightening of the Body Axis

Reissner’s fiber (RF) is a secreted filament that floats in the neural canal of chordates. Since its discovery in 1860, there has been no agreement on its primary function, and its strong conservation across chordate species has remained a mystery for comparative neuroanatomists. Several findings, including the chemical composition and the phylogenetic history of RF, clinical observations associating RF with the development of the neural canal, and more recent studies suggesting that RF is needed to develop a straight vertebral column, may shed light on the functions of this structure across chordates. In this article, we will briefly review the evidence mentioned above to suggest a role of RF in the origin of fundamental innovations of the chordate body plan, especially the elongation of the neural tube and maintenance of the body axis. We will also mention the relevance of RF for medical conditions like hydrocephalus, scoliosis of the vertebral spine and possibly regeneration of the spinal cord.

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Faculty Opinions recommendation of A Gradient of Glycolytic Activity Coordinates FGF and Wnt Signaling during Elongation of the Body Axis in Amniote Embryos.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727347913.793529641 ◽

2017 ◽

Author(s):

Benjamin Feldman

Keyword(s):

Wnt Signaling ◽

The Body ◽

Body Axis ◽

Glycolytic Activity

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Black spicules from a new interstitial opheliid polychaete Thoracophelia minuta sp. nov. (Annelida: Opheliidae)

Scientific Reports ◽

10.1038/s41598-020-80702-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Naoto Jimi ◽

Shinta Fujimoto ◽

Mami Takehara ◽

Satoshi Imura

Keyword(s):

Developmental Biology ◽

Phylogenetic Analysis ◽

New Species ◽

Morphological Diversity ◽

The Body ◽

Evolutionary Significance ◽

Research Subject ◽

Ecological Diversity ◽

Coelomic Cavity ◽

Molecular Phylogenetic

AbstractThe phylum Annelida exhibits high morphological diversity coupled with its extensive ecological diversity, and the process of its evolution has been an attractive research subject for many researchers. Its representatives are also extensively studied in fields of ecology and developmental biology and important in many other biology related disciplines. The study of biomineralisation is one of them. Some annelid groups are well known to form calcified tubes but other forms of biomineralisation are also known. Herein, we report a new interstitial annelid species with black spicules, Thoracophelia minuta sp. nov., from Yoichi, Hokkaido, Japan. Spicules are minute calcium carbonate inclusions found across the body and in this new species, numerous black rod-like inclusions of calcium-rich composition are distributed in the coelomic cavity. The new species can be distinguished from other known species of the genus by these conspicuous spicules, shape of branchiae and body formula. Further, the new species’ body size is apparently smaller than its congeners. Based on our molecular phylogenetic analysis using 18S and 28S sequences, we discuss the evolutionary significance of the new species’ spicules and also the species' progenetic origin.

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Development of a new method for assessing otolith function in mice using three-dimensional binocular analysis of the otolith-ocular reflex

Scientific Reports ◽

10.1038/s41598-021-96596-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shotaro Harada ◽

Takao Imai ◽

Yasumitsu Takimoto ◽

Yumi Ohta ◽

Takashi Sato ◽

...

Keyword(s):

Eye Movement ◽

Three Dimensional ◽

Vertical Component ◽

Inertial Force ◽

Linear Acceleration ◽

The Body ◽

Body Axis ◽

Gravitational Acceleration ◽

Ocular Reflex ◽

Translational Movement

AbstractIn the interaural direction, translational linear acceleration is loaded during lateral translational movement and gravitational acceleration is loaded during lateral tilting movement. These two types of acceleration induce eye movements via two kinds of otolith-ocular reflexes to compensate for movement and maintain clear vision: horizontal eye movement during translational movement, and torsional eye movement (torsion) during tilting movement. Although the two types of acceleration cannot be discriminated, the two otolith-ocular reflexes can distinguish them effectively. In the current study, we tested whether lateral-eyed mice exhibit both of these otolith-ocular reflexes. In addition, we propose a new index for assessing the otolith-ocular reflex in mice. During lateral translational movement, mice did not show appropriate horizontal eye movement, but exhibited unnecessary vertical torsion-like eye movement that compensated for the angle between the body axis and gravito-inertial acceleration (GIA; i.e., the sum of gravity and inertial force due to movement) by interpreting GIA as gravity. Using the new index (amplitude of vertical component of eye movement)/(angle between body axis and GIA), the mouse otolith-ocular reflex can be assessed without determining whether the otolith-ocular reflex is induced during translational movement or during tilting movement.

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Isograft and xenograft of the subcommissural organ into the lateral ventricle of the rat and the formation of Reissner's fiber

Cell and Tissue Research ◽

10.1007/s004410051306 ◽

1999 ◽

Vol 296 (3) ◽

pp. 457-469 ◽

Cited By ~ 7

Author(s):

S. Rodríguez ◽

E. H. Navarrete ◽

K. Vio ◽

C. González ◽

K. Schöbitz ◽

...

Keyword(s):

Lateral Ventricle ◽

Subcommissural Organ ◽

Reissner's Fiber ◽

Reissner’S Fiber

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Effects of SCO-spondin thrombospondin type 1 repeats (TSR) in comparison to Reissner's fiber material on the differentiation of the B104 neuroblastoma cell line

Cell and Tissue Research ◽

10.1007/s004410100383 ◽

2001 ◽

Vol 304 (3) ◽

pp. 361-369 ◽

Cited By ~ 14

Author(s):

El-Bitar F. ◽

Bamdad M. ◽

Dastugue B. ◽

Meiniel A.

Keyword(s):

Cell Line ◽

Neuroblastoma Cell ◽

Fiber Material ◽

Neuroblastoma Cell Line ◽

Reissner's Fiber ◽

Reissner’S Fiber ◽

Thrombospondin Type 1 Repeats

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The Caenorhabditis elegans gene lin-44 controls the polarity of asymmetric cell divisions

Development ◽

10.1242/dev.120.5.1035 ◽

1994 ◽

Vol 120 (5) ◽

pp. 1035-1047 ◽

Cited By ~ 13

Author(s):

M.A. Herman ◽

H.R. Horvitz

Keyword(s):

Caenorhabditis Elegans ◽

The Body ◽

Body Axis ◽

Nematode Caenorhabditis Elegans ◽

Asymmetric Cell Divisions ◽

Cell Divisions ◽

Sister Cells

The generation and orientation of cellular and organismic polarity are fundamental aspects of development. Mutations in the gene lin-44 of the nematode Caenorhabditis elegans reverse both the relative positions of specific sister cells and the apparent polarities of these cells. Thus, lin-44 mutants appear to generate polar cells but to misorient these cells along the body axis of the animal. We postulate that lin-44 acts to specify the orientation of polar cells.

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Head positioning control in a gravito-inertial field and in normal gravity

Journal of Vestibular Research ◽

10.3233/ves-2004-14402 ◽

2004 ◽

Vol 14 (4) ◽

pp. 321-333

Author(s):

Frédéric Sarès ◽

Christophe Bourdin ◽

Jean-Michel Prieur ◽

Jean-Louis Vercher ◽

Jean-Pierre Menu ◽

...

Keyword(s):

Inertial Force ◽

The Body ◽

Body Axis ◽

Positioning Control ◽

Head Positioning ◽

Subject Variability ◽

Visual Frame ◽

Vector Orientation ◽

The Right ◽

Within Subject Variability

The way in which the head is controlled in roll was investigated by dissociating the body axis and the gravito-inertial force orientation. Seated subjects (N = 8) were requested to align their head with their trunk, 30° to the left, 30° to the right or with the gravito-inertial vector, before, during (Per Rotation), after off-center rotation and on a tilted chair without rotation (Tilted). The gravito-inertial vector angle during rotation and the chair tilt angle were identical (17°). The subjects were either in total darkness or facing a visual frame that was fixed to the trunk. Both final error and within-subject variability of head positioning increased when the body axis and the gravito-inertial vector were dissociated (Per Rotation and Tilted). However, the behavior was different depending on whether the subjects were in the Tilted or Per Rotation conditions. The presentation of the visual frame reduced the within-subject variability and modified the perception of the gravito-inertial vector's orientation on the tilted chair. As head positioning with respect to the body and sensing of the gravito-inertial vector are modified when body axis and gravito-inertial vector orientation are dissociated, the observed decrease in performance while executing motor tasks in a gravito-inertial field may be at least in part attributed to the inaccurate sensing of head position.

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