XIV.—Male Haploidy and Female Diploidy in Sirex cyaneus F. (Hymen.)

1932 ◽  
Vol 51 ◽  
pp. 97-103 ◽  
Author(s):  
A. D. Peacock ◽  
R. A. R. Gresson
Keyword(s):  
Reproductive Tissue ◽  
Chromatoid Body ◽  
Cytoplasmic Granules ◽  
Male Gametes ◽  
Male Reproductive Tissue ◽  
Chromatoid Bodies ◽  
Diploid Organism

Summary1. From the above it is therefore justifiable to conclude that Sirex cyaneus is typically hymenopterous, in that:(a) the ripe male reproductive tissue is haploid (8 chromosomes), while the female oogonia are diploid (16 chromosomes);(b) the abortive character of the first spermatocyte division is evidence that chromosome reduction does not occur during the maturation of the male gametes.2. Support is thus afforded to the hypothesis commonly held, that the male hymenopteron is a haploid organism and is the product of an unfertilised (haploid) egg, while the female is a diploid organism arising from a fertilised egg.3. Feulgen's “Nuclealreaktion” holds for the chromatin involved in the abortive division and for the chromosomes of the second spermatocyte; but the large chromatoid body and cytoplasmic granules seen in these same stages by the iron hæmatoxylin technique did not give the chromatin reaction. The nature of these chromatoid bodies remains to be discovered.

The Chromatoid Body in Syrian Hamster Spermatocytes: Its Morphology and Distinctive Characteristics

1967 ◽  
Vol 25 ◽  
pp. 214-215
Author(s):  
A. Krishan ◽  
B. G. Uzman
Keyword(s):  
Syrian Hamster ◽  
Developmental Stages ◽  
Mammalian Species ◽  
Chromatoid Body ◽  
Similar Material ◽  
Nuclear Pores ◽  
Dense Granules ◽  
Cytoplasmic Structure ◽  
Close Proximity ◽  
Chromatoid Bodies

The chromatoid body (“sphere chromatophile”) has recently been characterized in the developmental stages of animal sperm cells as a cytoplasmic structure rich in RNA and basic proteins but containing no DNA. In electron micrographs of widely divergent species several different structures have been designated chromatoid bodies: aggregates of dense granules; bodies with concentric membranous substructure; and tubules (500 A in diameter) arranged in parallel array.We shall describe, in early spermatocytes of the Syrian hamster, masses of fine, amorphous, electron-dense material adjacent to the nuclear membrane often in close proximity to nuclear pores (Figure 1); similar material has been so identified in other mammalian species. In later spermatocytes and in spermatids, this same material is recognized closely associated with the centriolar area which in these stages lies at the posterior end of the nucleus or sperm head.

scholarly journals Aging and chromatoid body assembly: Are these two physiological events linked?

2018 ◽  
Vol 243 (11) ◽  
pp. 917-925 ◽  
Author(s):  
Elisa G Santos ◽  
Maraisa A Silva ◽  
Renata P Amorim ◽  
Leticia de Souza Giordano ◽  
Dayana de Sales Silva ◽  
...  
Keyword(s):  
Germ Cell ◽  
Structural Changes ◽  
Morphological Changes ◽  
Sperm Count ◽  
Cell Structure ◽  
Male Germ Cell ◽  
Seminiferous Tubules ◽  
Chromatoid Body ◽  
Adult Mice ◽  
Chromatoid Bodies

The chromatoid body is a cytoplasmic male germ cell structure that plays a role in the regulation of mRNA transcription during spermatogenesis. A proteomic analysis of this structure has identified the presence of its classic molecular markers (MVH and MIWI), as well as a significant number of transient proteins. Circadian locomotor output cycles protein kaput (CLOCK) and brain and muscle ARNT-like 1 (BMAL1), which are molecular components of the circadian clock, are likely located in the chromatoid body in a transient fashion. This study sought to determine whether aging produces morphological changes in the chromatoid bodies of round spermatids similar to those previously observed in BMAL1 knockout mice. A sample of 30 male mice was divided into three groups: juvenile mice (45 days old), adult mice (120 days old), and old mice (+180 days old). Aging was confirmed by viability and sperm count analyses and testosterone dosage. Squash slides prepared with fragments of seminiferous tubules were immunostained for MVH, MIWI, BMAL1, and CLOCK detection. In juvenile and adult specimens, single round chromatoid bodies were observed using MVH/BMAL1 and MIWI/CLOCK immunostaining. In old specimens, many chromatoid bodies displayed changes in number and morphology, as well as an increase in the interactions between MVH and BMAL1; MIWI and CLOCK. Changes in chromatoid body morphology increased interactions between the proteins analyzed herein, and decreased amounts of these proteins in seminiferous tubules of older mice may indicate that aging influences the assembly and physiology of chromatoid bodies, which may, in turn, affect fertility. Impact statement The results discussed in this paper indicate that aging compromises the structure and physiology of chromatoid bodies (CBs) in post-meiotic male cells. Since CB is a fundamental structure for the differentiation of the mature male germ cell it is possible that this imbalance in CB physiology may play a role in the reduction of fertility in older men. It is important to note that not only the classic CB markers (such as the MIWI and MVH proteins) were used to showcase the structural changes in the CBs but also the main components of circadian cycle control (the CLOCK and BMAL1 proteins), indicating that the reduction of circadian control in aged males may contribute to these changes in CBs as well. Therefore, it is intriguing to evaluate the hypothesis that controlling these physiological/structural changes in CBs may be a way of delaying the effects of aging in males.

A Comparison of the Formation and Structure of the Chromatoid Body in Two Strains of Entamoeba Histolytica

1967 ◽  
Vol 25 ◽  
pp. 14-15
Author(s):  
J. H. Miller ◽  
E. C. Nelson
Keyword(s):  
Light Microscopy ◽  
Entamoeba Histolytica ◽  
Intestinal Tract ◽  
Growth Characteristics ◽  
Chromatoid Body ◽  
Chromatoid Bodies ◽  
Entamoeba Invadens ◽  
Crystalline Array

Recent studies have shown that the chromatoid bodies of the Entamoebidae are composed primarily of RNA in a crystalline array of parallel rods, each consisting of pentagonal dodecahedra stacked linearly. These studies have been confined to Entamoeba invadens, an ameba in the intestinal tract of reptiles. Therefore, it was decided to examine the formation of chromatoid bodies in two strains of E. histolytica, the human intestinal ameba. The Laredo strain, considered by some not to be a true E. histolytica because of certain biochemical and growth characteristics, was compared to a strain isolated recently by one of us (E.C.N.). This strain was obtained from a case which exhibited classical symptoms. The morphology of this organism under light microscopy was typical of the species.Both strains were grown in Nelson's encystment medium, fixed in glutaraldehyde and osmium, embedded in Araldite and viewed in a Hitachi HU 11-A microscope.

Actin and RNA identification in the rat chromatoid body by means of protein A-gold and RNAse-gold techniques

1983 ◽  
Vol 41 ◽  
pp. 712-713
Author(s):  
B. L. Armbruster ◽  
H. Walt
Keyword(s):  
Messenger Rna ◽  
Protein A ◽  
Ultrastructural Level ◽  
Nuclear Pore ◽  
Nuclear Pore Complexes ◽  
Chromatoid Body ◽  
Major Function ◽  
High Resolution Autoradiography ◽  
Chromatoid Bodies ◽  
Pore Complexes

Differentiating spermatids display various forms of motility, the most obvious being microtubule-dynein motivated flagellar movements. Recent studies have demonstrated the presence of contractile proteins, in mammalian germinal epithelium, and some organelle movements seem to be based on an actin-myosin mechanism. Chromatoid bodies, found in the spermatocytes and spermatids of many animals, show directed movements around spermatid nuclei during differentiation. Although this phenomenon has been described frequently, the underlying motive force was not established. As the chromatoid body moves along the nuclear envelope towards the region of the differentiating acrosome, it established contact to intranuclear material through nuclear pore complexes. It has been postulated that nucleocytoplasmic RNA transport is a major function of the chromatoid body. Whereas light microsopic histochemical studies suggested the presence of RNA in this organelle, similar results were not found at the ultrastructural level. More recent studies by means of high resolution autoradiography supported that conclusion that the organelle contains long-lived messenger RNA for use in late spermiogenesis.

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