Experiments on blocking and unblocking of first meiotic metaphase in eggs of the parthenogenetic stick insect Carausius morosus Br. (Phasmida, Insecta)

Development ◽  
1976 ◽  
Vol 36 (2) ◽  
pp. 383-394
Author(s):  
L. P. Pijnacker ◽  
M. A. Ferwerda
Keyword(s):  
Interphase Nucleus ◽  
Stick Insect ◽  
Meiotic Metaphase ◽  
Anterior Region ◽  
Egg Cell ◽  
Metaphase Chromosomes ◽  
Carausius Morosus ◽  
Cytoplasmic Factors ◽  
Activating Agent ◽  
Nuclear Behaviour

The eggs of the parthenogenetic stick insect Carausius morosus, which remain arrested in first meiotic metaphase until oviposition, must be activated in order to develop. The activating agent is oxygen from the air, which enters the egg cell through the micropyle. An exposure shorter than one minute is sufficient to release the blockage. In non-activated (micropyle-less) eggs the first metaphase chromosomes either degenerate or change into an interphase nucleus. This nucleus polyploidizes by endoreduplication, and then either degenerates or multiplies by amitosis. Similarly more generations of nuclei may arise resulting in a chaotic development. These nuclei survive better in the anterior region of the egg. The question of whether the cytoplasmic factors which control nuclear behaviour, also operate in eggs of C. morosus is discussed.

Sex chromosomes and origin of males and sex mosaics of the parthenogenetic stick insect Carausius morosus Br.

Chromosoma ◽  
1980 ◽  
Vol 79 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Laas P. Pijnacker ◽  
Margriet A. Ferwerda
Keyword(s):  
Sex Chromosomes ◽  
Stick Insect ◽  
Carausius Morosus

Hormonal Control of the Malpighian Tubules of the Stick Insect, Carausius Morosus

1970 ◽  
Vol 52 (3) ◽  
pp. 653-665 ◽  
Author(s):  
DIANA E. M. PILCHER
Keyword(s):  
Stick Insect ◽  
Hormonal Control ◽  
The State ◽  
Malpighian Tubules ◽  
Suboesophageal Ganglion ◽  
Carausius Morosus ◽  
Corpora Cardiaca ◽  
Diuretic Hormone ◽  
The Brain

1. Urine secretion by isolated Malpighian tubules of Carausius is accelerated by a diuretic hormone which can be extracted from the brain, corpora cardiaca and suboesophageal ganglion. 2. The level of this hormone in the haemolymph varies according to the state of hydration of the insect. 3. The hormone is inactivated by the tubules, and a mechanism is proposed whereby the tubules might be controlled by the hormone in vivo.

Memoirs: The Embryonic Development of the Stick-Insect, Carausius morosus

1936 ◽  
Vol s2-78 (311) ◽  
pp. 487-511
Author(s):  
A. J. THOMAS
Keyword(s):  
Embryonic Development ◽  
Stick Insect ◽  
Malpighian Tubules ◽  
Germ Band ◽  
Ventral Plate ◽  
Carausius Morosus ◽  
Gut Epithelium ◽  
Cleavage Nucleus ◽  
Endodermal Cells ◽  
Late Stages

1. The maturation of the egg takes place in the ovarian tube, and is immediately followed by the formation of the cleavagenucleus and its division into many nuclei. 2. The entire products of the cleavage-nucleus migrate to the surface to form the blastoderm. Cleavage of the yolk was not observed even in late stages. Yolk-cells are absent when the blastoderm is being formed. 3. Primitive endodermal cells are proliferated from the middle of the germ-band, and form a membrane between the germ-band and the yolk. The membrane is present only in embryonic stages; some of the cells proliferated wander into the yolk and act as vitellophags. 4. Mesoderm is formed by proliferation of cells from the ventral plate. It is preceded by the formation of a shallow gastrular furrow, and from the bottom of this furrow proliferation takes place. The mesoderm becomes arranged in segmental masses. 5. Two masses of cells proliferated at the anterior and posterior ends of the germ-band are shown to be the endodermal rudiments from which the mid-gut epithelium is formed. The invaginations of the stomodaeum and proctodaeum grow against these masses and carry parts of the proliferating areas near their blind ends. It is shown that the various methods of mid-gut formation which have been described could be reconciled with the process described in Carausius. 6. The hinder end of the mid-gut is flanked by two plates of ectoderm which are forward extensions of the proctodaeum. Into these extensions the Malpighian tubules open, and, as their histology is identical with that of these extensions and widely different from that of the mid-gut, these tubules must be ectodermal in nature. 7. The formation of the amnion and serosa are described.

Calcium Action Potentials in the Skeletal Muscle Fibres of the Stick Insect Carausius Morosus

1981 ◽  
Vol 93 (1) ◽  
pp. 257-267 ◽  
Author(s):  
FRANCES M. ASHCROFT
Keyword(s):  
Action Potential ◽  
Action Potentials ◽  
Inhibitory Effect ◽  
Stick Insect ◽  
Muscle Fibres ◽  
Carausius Morosus ◽  
Outward Currents ◽  
Ca Antagonist ◽  
Ventral Longitudinal Muscle ◽  
Skeletal Muscle Fibres

The ionic requirements for the generation of action potentials in the ventral longitudinal muscle fibres of the stick insect, Carausius morosus, were investigated. Ca-free Ringer rapidly and reversibly abolished the action potential. In the presence of tetraethylammonium (TEA) ions (to suppress outward currents) the overshoot of the action potential changed 26 mV for a 10-fold change in [Ca]o. The maximum rate of rise of the action potential (measured in TEA Ringer) showed saturation at high [Ca]o. Cobaltous ions (20 mM) and the organic Ca antagonist D 600 (5×10−4g/ml) reversibly inhibited the action potential; the inhibitory effect of 1 mM-La3+ was irreversible. Barium and strontium, but not magnesium, were able to substitute for calcium as charge carriers. These results suggest that an inward movement of Ca2+ underlies the action potential of Carausius fibres.

Transcriptomic and Neuropeptidomic Analysis of the Stick Insect, Carausius morosus

2018 ◽  
Vol 17 (6) ◽  
pp. 2192-2204 ◽  
Author(s):  
Sander Liessem ◽  
Lapo Ragionieri ◽  
Susanne Neupert ◽  
Ansgar Büschges ◽  
Reinhard Predel
Keyword(s):  
Stick Insect ◽  
Carausius Morosus
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