Characterization of Drosophila Larval Crawling at the Level of Organism, Segment, and Somatic Body Wall Musculature

Over 30 Caenorhabditis elegans mutants were identified with normal muscle differentiation and initial locomotion followed by catastrophic detachment of skeletal muscles from the body wall. Reducing the strength of muscle contraction in these mutants with a myosin gene mutation suppresses muscle detachment. These dystrophic mutants identify a novel class of genes required for growth and maintenance of functional muscle attachments, not exceptional alleles of genes required for muscle differentiation and contractility. Nine new genes, named mua, and two previously published loci, unc-23 and vab-10, cause fragile musscle attachments. The primary sites of muscle detachment, including the plane of tissue separation, are characteristic for each gene. We suggest these genes identify feedback mechanisms whereby local strain regulates the extent of myofibril contraction and the placement of new muscle attachments in functioning muscles. Finally, we draw some comparisons to vertebrate skin fragility diseases and muscular dystrophies.

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The evolution of air-breathing respiratory faculties in craniotes

Respiratory Biology of Animals ◽

10.1093/oso/9780199238460.003.0015 ◽

2019 ◽

pp. 177-191

Author(s):

Steven F. Perry ◽

Markus Lambertz ◽

Anke Schmitz

Keyword(s):

High Performance ◽

Body Wall ◽

Structure And Function ◽

Control Of Breathing ◽

Body Wall Muscle ◽

Positive Pressure ◽

Limiting Factor ◽

Swim Bladder ◽

Body Wall Musculature ◽

And Function

The origin of lungs from a swim bladder, swim bladder from lungs, or both from a relatively undifferentiated respiratory pharynx remains unresolved. Once present, the lungs can be ventilated by a positive-pressure buccal pump, which can be easily derived from the gill ventilation sequence in a lungfish, or by negative-pressure aspiration. Although aspiration breathing is characteristic of amniotes, it has also been observed in a lungfish and body wall muscle contraction in response to respiratory stimuli has even been reported in lamprey larvae. The hypaxial body wall musculature used for aspiration breathing is also necessary for locomotion in most amniotes, just when respiratory demand is greatest. This paradox, called Carrier’s constraint, is a major limiting factor in the evolution of high-performance faculties, and the evolution of anatomical and physiological specializations that circumvent it characterize most major amniote groups. Serendipitous combinations have resulted in evolutionary cascades and high-performance groups such as birds and mammals. Complementing evolution are the capacities for acclimatization and adaptation not only in the structure and function of the gas exchanger, but also in the control of breathing and the composition of the blood.

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A role for adenosine in metabolic depression in the marine invertebrate Sipunculus nudus

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1997.272.1.r350 ◽

1997 ◽

Vol 272 (1) ◽

pp. R350-R356 ◽

Cited By ~ 7

Author(s):

A. Reipschlager ◽

G. E. Nilsson ◽

H. O. Portner

Keyword(s):

Body Wall ◽

Marine Invertebrate ◽

Coelomic Fluid ◽

Metabolic Depression ◽

O2 Consumption ◽

Experimental Conditions ◽

Indwelling Catheter ◽

Sipunculus Nudus ◽

Body Wall Musculature ◽

Concentration Changes

Involvement of neurotransmitters in metabolic depression under hypoxia and hypercapnia was examined in Sipunculus nudus. Concentration changes of several putative neurotransmitters in nervous tissue during anoxic or hypercapnic exposure or during combined anoxia and hypercapnia were determined. Among amino acids (gamma-aminobutyric acid, glutamate, glycine, taurine, serine, and aspartate) and monoamines (serotonin, dopamine, and norepinephrine), some changes were significant, but none were consistent with metabolic depression under all experimental conditions applied. Only the neuromodulator adenosine displayed concentration changes in accordance with metabolic depression under all experimental conditions. Levels increased during anoxia, during hypercapnia, and to an even greater extent during anoxic hypercapnia. Adenosine infusions into coelomic fluid via an indwelling catheter induced a significant depression of the normocapnic rate of O2 consumption from 0.36 +/- 0.04 to a minimum of 0.24 +/- 0.02 (SE) mumol.g-1.h-1 after 90 min (n = 6). Application of the adenosine antagonist theophylline caused a transient rise in O2 consumption 30 min after infusion during hypercapnia but not during normocapnia. Effects of adenosine and theophylline were observed in intact individuals but not in isolated body wall musculature. The results provide evidence for a role of adenosine in inducing metabolic depression in S. nudus, probably through the established effects of decreasing neuronal excitability and neurotransmitter release. In consideration of our previous finding that metabolic depression in isolated body wall musculature was elicited by extracellular acidosis, it is concluded that central and cellular mechanisms combine to contribute to the overall reduction in metabolic rate in S. nudus.

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Preparation and Characterization of Anti-CeTNT-1 and Anti-CeTNT-4 Antibodies

Bangladesh Journal of Scientific and Industrial Research ◽

10.3329/bjsir.v44i3.4413 ◽

1970 ◽

Vol 44 (3) ◽

pp. 371-376

Author(s):

M Ziaul Amin ◽

Hiroaki Kagawa ◽

Mohammed A Satter

Keyword(s):

Fusion Proteins ◽

Tissue Specificity ◽

Body Wall ◽

Troponin T ◽

Specific Interaction ◽

The Body ◽

Expression Vectors ◽

Antibody Specificity ◽

Sds Page

Among the four CeTNT isoforms, CeTNT-1, CeTNT-2 are body wall types, CeTNT-4 is pharynx type and CeTNT-3 is expressed in both the body wall and pharyngeal tissue. In our previous study, we used body wall and pharynx type anti-CeTNI, anti-CeTNC and anti-CeTM antibodies to observe the tissue specific interaction of the TNI isoforms with others TN subunits and tropomyosin isoforms. To extent the interaction study of CeTNT isoforms, in this study, we prepared and characterized the body wall type anti-CeTNT-1 and pharynx type anti- CeTNT-4 antibodies. For the preparation of the anti-CeTNT-1 and anti-CeTNT-4 antibodies, in this study we constructed the pCTNT-1 and pCTNT-4 expression vectors. The sub-cloned of the pCTNT-1 and pCTNT-4 expression vectors were verified by DNA sequencing. These expression vectors were used to generate fusion proteins of the body wall, TNT-1 and pharyngeal TNT-4 isoforms in Escherichia Ecoli. The expression of these fusion proteins were confirmed by SDS-PAGE analysis. The anti-CeTNT-1 and anti-CeTNT-4 antibodies were prepared in the rabbit by using the gel cut of the CeTNT-1 and CeTNT-4 fusion proteins. The antibody specificity of the CeTNT-1 and CeTNT-4 fusion proteins was also judged by Western-analysis using prepared anti-CeTNT-1 and anti-CeTNT-4 antibodies. The antibody specificity results indicated that anti-sera against each of both the body wall type TNT-1 and pharynx type TNT-4 isoforms had tissue specificity. Key words: Troponin T, Caenorhabditis elegans, Body wall, Pharynx DOI: 10.3329/bjsir.v44i3.4413 Bangladesh J. Sci. Ind. Res. 44(3), 371-376, 2009

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The Fine Structure of Some Blood Vessels of the Earthworm, Eisenia foetida

The Journal of Cell Biology ◽

10.1083/jcb.7.4.717 ◽

1960 ◽

Vol 7 (4) ◽

pp. 717-724 ◽

Cited By ~ 61

Author(s):

Kiyoshi Hama

Keyword(s):

Fine Structure ◽

Basement Membrane ◽

Body Wall ◽

Circular Muscle ◽

Muscle Layer ◽

Eisenia Foetida ◽

Longitudinal Muscle Layer ◽

Cell Processes ◽

Body Wall Musculature ◽

Blood Pigment

The fine structure of the main dorsal and ventral circulatory trunks and of the subneural vessels and capillaries of the ventral nerve cord of the earthworm, Eisenia foetida, has been studied with the electron microscope. All of these vessels are lined internally by a continuous extracellular basement membrane varying in thickness (0.03 to 1 µ) with the vessel involved. The dorsal, ventral, and subneural vessels display inside this membrane scattered flattened macrophagic or leucocytic cells called amebocytes. These lie against the inner lining of the basement membrane, covering only a small fraction of its surface. They have long, attenuated branching cell processes. All of these vessels are lined with a continuous layer of unfenestrated endothelial cells displaying myofilaments and hence qualifying for the designation of "myoendothelial cells." The degree of muscular specialization varies over a spectrum, however, ranging from a delicate endowment of thin myofilaments in the capillary myoendothelial cells to highly specialized myoendothelial cells in the main pulsating dorsal blood trunk, which serves as the worm's "heart" or propulsive "aorta." The myoendothelial cells most specialized for contraction display well organized sarcoplasmic reticulum and myofibrils with thick and thin myofilaments resembling those of the earthworm body wall musculature. In the ventral circulatory trunk, circular and longitudinal myofilaments are found in each myoendothelial cell. In the dorsal trunk, the lining myoendothelial cells contain longitudinal myofilaments. Outside these cells are circular muscle cells. The lateral parts of the dorsal vessels have an additional outer longitudinal muscle layer. The blood plasma inside all of the vessels shows scattered particles representing the circulating earthworm blood pigment, erythrocruorin.

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