The development of a biological novelty: a different way to make appendages as revealed in the snout of the star-nosed mole Condylura cristata

1999 ◽  
Vol 202 (20) ◽  
pp. 2719-2726
Author(s):  
K.C. Catania ◽  
R.G. Northcutt ◽  
J.H. Kaas
Keyword(s):  
Body Wall ◽  
Developmental Process ◽  
Deep Layer ◽  
The Body ◽  
Embryonic Stage ◽  
Unique Pattern ◽  
Appendage Development ◽  
The Face ◽  
Appendage Formation ◽  
Condylura Cristata

The nose of the star-nosed mole Condylura cristata is a complex biological novelty consisting of 22 epidermal appendages. How did this new set of facial appendages arise? Recent studies find remarkable conservation of the genes expressed during appendage formation across phyla, suggesting that the basic mechanisms for appendage development are ancient. In the nose of these moles, however, we find a unique pattern of appendage morphogenesis, showing that evolution is capable of constructing appendages in different ways. During development, the nasal appendages of the mole begin as a series of waves in the epidermis. A second deep layer of epidermis then grows under these superficial epidermal waves to produce 22 separate, elongated epidermal cylinders embedded in the side of the mole's face. The caudal end of each cylinder later erupts from the face and rotates forward to project rostrally, remaining attached only at the tip of the snout. As a result of this unique ‘unfolding’ formation, the rostral end of each adult appendage is derived from caudal embryonic facial tissue, while the caudal end of each appendage is derived from rostral facial tissue. This developmental process has essentially no outgrowth phase and results in the reversal of the original embryonic orientation of each appendage. This differs from the development of other known appendages, which originate either as outgrowths of the body wall or from subdivisions of outgrowths (e.g. tetrapod digits). Adults of a different mole species (Scapanus townsendii) exhibit a star-like pattern that resembles an embryonic stage of the star-nosed mole, suggesting that the development of the star recapitulates stages of its evolution.

The ultrastructure of the giant cell surrounding larvae of Thelazia spp. (Nematoda: Thelazioidea) in the face fly, Musca autumnalis De Geer

1985 ◽  
Vol 63 (10) ◽  
pp. 2352-2363 ◽  
Author(s):  
John G. Stoffolano Jr. ◽  
Lucy R. S. Yin
Keyword(s):  
Endoplasmic Reticulum ◽  
Body Wall ◽  
Giant Cells ◽  
The Body ◽  
Tissue Response ◽  
Cell Junctions ◽  
Annulate Lamellae ◽  
Defensive Reaction ◽  
The Face ◽  
Musca Autumnalis

The larval nematode, Thelazia spp., initiates a tissue response by the body-wall epidermal cells of its normal intermediate host, Musca autumnalis, resulting in the formation of giant cells. These giant cells differ in several ways from hemocytic capsules: they are larger, lack signs of necrosis, protect the parasite, and represent a true syncytium. Both, however, are considered to be the result of a defensive reaction by the host. Giant cells contain the following organelles which are absent from hemocytic capsules: hypertrophied nuclei, smooth-surfaced endoplasmic reticulum, and annulate lamellae. Further, unlike hemocytic capsules, giant cells lack cell junctions and cytolysosomes. Formation of giant cells is considered beneficial to both the host and the parasite.

Questions on the role of biofilms for the adaptation of microorganisms to unfavorable environmental factors by the example of P. aeruginosa

2020 ◽  
Vol 99 (4) ◽  
pp. 379-383
Author(s):  
Vasily N. Afonyushkin ◽  
N. A. Donchenko ◽  
Ju. N. Kozlova ◽  
N. A. Davidova ◽  
V. Yu. Koptev ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Barrier Function ◽  
Infectious Agent ◽  
Antagonistic Activity ◽  
The Body ◽  
Main Function ◽  
Pathogenic Potential ◽  
The Face

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

Lymphangiomatosis of the Body Wall: A Report of Two Cases Associated with Chylothorax and Fatal Outcome

1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  
Body Wall ◽  
Fatal Outcome ◽  
The Body

scholarly journals A screen for genetic loci required for body-wall muscle development during embryogenesis in Caenorhabditis elegans.

Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire
Keyword(s):  
Caenorhabditis Elegans ◽  
Myosin Heavy Chain ◽  
Muscle Cell ◽  
Heavy Chain ◽  
Body Wall ◽  
Muscle Development ◽  
Contractile Function ◽  
The Body ◽  
Body Wall Muscle ◽  
Genetic Loci

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.

scholarly journals Cloning and sequencing of cDNA of Sarcophaga peregrina humoral lectin induced on injury of the body wall.

1985 ◽  
Vol 260 (22) ◽  
pp. 12228-12233 ◽  
Author(s):  
H Takahashi ◽  
H Komano ◽  
N Kawaguchi ◽  
N Kitamura ◽  
S Nakanishi ◽  
...  
Keyword(s):  
Body Wall ◽  
The Body ◽  
Cloning And Sequencing

scholarly journals Mutations Affecting Nerve Attachment of Caenorhabditis elegans

Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1611-1622 ◽  
Author(s):  
Go Shioi ◽  
Michinari Shoji ◽  
Masashi Nakamura ◽  
Takeshi Ishihara ◽  
Isao Katsura ◽  
...  
Keyword(s):  
Caenorhabditis Elegans ◽  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Body Wall ◽  
The Body ◽  
Genetic Loci ◽  
Muscle Attachment ◽  
C Elegans ◽  
Ventral Cord ◽  
Excretory Canal

Abstract Using a pan-neuronal GFP marker, a morphological screen was performed to detect Caenorhabditis elegans larval lethal mutants with severely disorganized major nerve cords. We recovered and characterized 21 mutants that displayed displacement or detachment of the ventral nerve cord from the body wall (Ven: ventral cord abnormal). Six mutations defined three novel genetic loci: ven-1, ven-2, and ven-3. Fifteen mutations proved to be alleles of previously identified muscle attachment/positioning genes, mup-4, mua-1, mua-5, and mua-6. All the mutants also displayed muscle attachment/positioning defects characteristic of mua/mup mutants. The pan-neuronal GFP marker also revealed that mutants of other mua/mup loci, such as mup-1, mup-2, and mua-2, exhibited the Ven defect. The hypodermis, the excretory canal, and the gonad were morphologically abnormal in some of the mutants. The pleiotropic nature of the defects indicates that ven and mua/mup genes are required generally for the maintenance of attachment of tissues to the body wall in C. elegans.

Circadian tuning of motivation. A little organ of yesterday?

1995 ◽  
Vol 7 (2) ◽  
pp. 21-23 ◽  
Author(s):  
S. Daan
Keyword(s):  
Internal State ◽  
External Environment ◽  
Animal Behaviour ◽  
The Body ◽  
Biological Clocks ◽  
Motivational Systems ◽  
Regulatory Principle ◽  
The Face ◽  
Temporal Organisation ◽  
The Ideal

The analysis of motivational systems underlying temporal organisation in animal behaviour has relied primarily on two conceptual functional frameworks: Homeostasis and biological clocks. Homeostasis is one of the most general and influential concepts in physiology. Walter Cannon introduced homeostasis as a universal regulatory principle which animals employ to maintain constancy of their ‘internal milieu’ in the face of challenges and perturbations from the external environment. Cannon spoke of “The Wisdom of the Body”, the collective of responses designed to defend the ideal internal state against those perturbations.

The cuticle of adultNippostrongylus brasiliensis

Parasitology ◽  
1965 ◽  
Vol 55 (1) ◽  
pp. 173-181 ◽  
Author(s):  
D. L. Lee
Keyword(s):  
Electron Microscope ◽  
Body Wall ◽  
Technical Assistance ◽  
Cortical Layer ◽  
The Body ◽  
Collagen Fibrils ◽  
Intestinal Cells ◽  
Nippostrongylus Brasiliensis ◽  
Normal Appearance

The cuticle of adults ofNippostrongylus brasiliensishas been described using histological, histochemical and ultrastructural techniques.The cuticle has the following layers: an outer triple-layered membrane; a single cortical layer; a fluid-filled layer which is traversed by numerous collagen fibrils; struts which support the fourteen longitudinal ridges of the cuticle and which are suspended by collagen fibrils in the fluid-filled layer; two fibre layers, each layer apparently containing three layers of fibres; and a basement lamella.The fluid-filled layer contains haemoglobin and esterase.The muscles of the body wall are attached to either the basement lamella or to the fibre layers of the cuticle.The mitochondria of the hypodermis are of normal appearance.The longitudinal ridges of the cuticle appear to abrade the microvilli of the intestinal cells of the host.Possible functions of the cuticle are discussed.I wish to thank Dr P. Tate, in whose department this work was done, for helpful suggestions and criticism at all stages of this work, and Mr A. Page for technical assistance. I also wish to thank Professor Boyd for permission to use the electron microscope in the Department of Anatomy.

Lymphangiomatosis of the Body Wall: A Report of Two Cases Associated with Chylothorax and Fatal Outcome

1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  
Body Wall ◽  
Fatal Outcome ◽  
The Body
Sign in / Sign up

Export Citation Format

Share Document