• Applied Microscopy
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• v.33 no.3
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• pp.243-250
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• 2003

Ultrastructural changes of the male germ cells and structure of spermatozoa in Paralichthys olivaceus were examined by means of the light and transmission electron microscopes. The spermatogonium has a large nucleus with a single nucleus with a single nucleolus in the interphase. Primary spermatocytes are identified by the formation of the synaptonemal complex in the karyoplasm. The secondary spermatocytes are more concentrated and contains numerous cell organelle in the cytoplasm. The nucleus of spermatid in spermiogenesis is more condensed in the karyoplasm, and show spherical structure in shape. Mitochondria of the spermatids are observed in the lower portion of the nucleus. The spermatozoon consists of the head, mid piece and tail. The acrosome is not observed in the head. Axial filaments of the flagellum consists of nine pairs of the peripheral microtubules and one pair of the central microtubules.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.5-5
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• 2002

Nucleoside diphosphate kinases (NDPKs) are conserved through evolution and have been shown to be involved in various biological phenomena. By functional screening in yeast, we identified a new member of the NDPK family, ㎚23-M5, which encodes a 211-amino acid protein with 86% identify to the human homolog, ㎚23-H5. Northern blot analysis reveals that ㎚23-M5 encodes two transcripts of 0.8 and 0.7 kb, which are highly and specifically expressed in adult testis. Reverse transcriptase polymerase chain reaction analysis shows that nm23-M5 first appears in pachytene spermatocytes and increase chain reaction in abundance through subsequent stages. (omitted)

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.97-97
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• 2002

Achieving of in vitro development for mammalian premature spermatogenic cells are very difficult. In-vitro culture of spermatogenic cells were then initiated in an effort to try to study in vivo spermatogenesis and to understand its molecular events. Recently, the morphogenetic changes of spermatocytes or spermatid by in-vitro culture system were achieved. (omitted)

• BMB Reports
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• v.45 no.1
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• pp.7-13
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• 2012

Phospholipase D (PLD), a superfamily of signaling enzymes that most commonly generate the lipid second messenger Phosphatidic Acid (PA), is found in diverse organisms from bacteria to man and functions in multiple cellular pathways. A fascinating member of the family, MitoPLD, is anchored to the mitochondrial surface and has two reported roles. In the first role, MitoPLD-generated PA regulates mitochondrial shape through facilitating mitochondrial fusion. In the second role, MitoPLD performs a critical function in a pathway that creates a specialized form of RNAi required by developing spermatocytes to suppress transposon mobilization during meiosis. This spermatocyte-specific RNAi, known as piRNA, is generated in the nuage, an electron-dense accumulation of RNA templates and processing proteins that localize adjacent to mitochondria in a structure also called intermitochondrial cement. In this review, we summarize recent findings on these roles for MitoPLD functions, highlighting directions that need to be pursued to define the underlying mechanisms.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.269-274
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• 1990

Chromosome complements of Japanese quail (Coturnix coturnix japonica) were studied using several tissues which involving testis, leukocytes and embryos. The diploid count was estimated to be 2n＝78. Analyzing the metaphase of secondary meiosis in spermatocytes, the haploid count estimated to be n＝39. Morphometric analysis were studied by the centromeric index and relative length of 8 macro-chromosomes and Z, W chromosomes The differences of morphological feature were not significant among tissues. Exceptionally the chromosome 4 shelved a considerable variety in the presence of it's short arm.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.2
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• pp.171-181
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• 1999

We examined the ultrastructure of eupyrene and apyrene spermatogenesis in the testis of Helicoverpa assulta (Lepidoptera: Noctuidae). The spermatogenesis was progressed near the fringe adjacent to the follicular layer of the testicular follicle, surrounding the apical cell concentrically. Eupyrene and apyrene were firstly distinguished at the telophase stage of the primary spermatocyte. Chromatin was evenly scattered in eupyrene nuclei, whereas it was lumped near the nuclear envelope in apyrene spermatogenesis. Then, the nucleus of eupyrene was transformed into two daughter nuclei by meiosis, while the nucleus of apyrene was divided into many micronuclei by irregular meiosis. After the meiosis was completed, a number of mitochondria in the cytoplasm of the early spermatids of the eupyrene and the apyrene were fused into one nebenkern. Also, as axial filament was formed due to the elongation of the spermatid, the nebenkern became splitted into mitochondrial derivatives. An acrosome precursor was present only in the eupyrene, attached to nuclear envelope.

• Journal of Korean Biological Nursing Science
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• v.1 no.1
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• pp.42-55
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• 1999

The purpose of this study was to investigate the effect of cyclophosphamide on the mouse seminiferous tubules by transmission electron microscopy at different groups: a control group, a group treated one time a week, and a group treated two times a week. Cyclophosphamide was injected in the intraperitoneal at a dosage of level 200mg/kg. The results obtained were as follows. 1. In the group of one time a week, pyknotic body and large vesicles were observed in cytoplasm of spermatogonium of seminiferous tubules, and in the intercellular space between spermatocytes, respectively. 2. In the group of two times a week, nucleus envelope in the spermatid was disrupted partially, observed vesicles in the nucleoplasm of spermatid, and separated or disrupted inner and outer membranes of mitochondria in the Sertoli cells.

• Environmental Analysis Health and Toxicology
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• v.17 no.1
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• pp.7-11
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• 2002

Effects of nonylphenol (NP) on gonadal development and growth of olive flounder, Paralichthys olivaceus were investigated. NP treatment was carried out to fry fish (during 55 to 64 days after hatching) using oral adminstration at nominal NP concentrations of 50, 100 and 150 tig/g BW Gonad before NP treatment was sexually undifferentiated as observed with mostly gonia cells. At 159 days after hatching, ovarian lamella of ovary were filled with oogonia and perinucleolus oocytes. On the other hand, testicular lobules of the testis were occupied by spermatogonia, spermatocytes and spermatids. Histological observation of ovary and testis development was any different between the control and NP treated groups. However, growth was significantly increased in NP treated groups than control groups (P< 0.05). These results considerate that NP has any effect for sex differentiation and gonadal development, but act for early growth in olive flounder.

• Toxicological Research
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• v.17 no.4
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• pp.267-272
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• 2001

This study was carried out to assess the reproductive toxicity of 2-bromopropane (S-BP) using spermatogenesis stage classification and Sertoli cell indices (SCI).Vehicle control olive oil and 2-BP doses of 125, 250 and 500 mg/kg of body weight were injected in the interaperitoneum of 12 weeks male Sprague-Dawley rats for 28 days respectively of SCI on germ cells including the spermatogonia of stages II-III, Ⅵ,Ⅹ, XII, ⅩIII, and spermatocytes of stages VIII (preleptotene), Ⅹ (leptotene), XII (leptotene), V and Ⅵ (pachytene), and the round spermatids of stage Ⅵ. Considering the process of maturation depletion in spermatonesis, spermatogonia may be the primary target cells of 2-BP toxicity.

• Korean Journal of Animal Reproduction
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• v.22 no.3
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• pp.245-252
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• 1998

The three-dimensional structure of the Sertoli cell in the rat was investigated by scanning electron microscopy. Morphologically, seven types of Sertoli cell processes were evident : Shrot, flat and ramified processes are projected from the lateral side of the basal portion of Sertoli cell. Leaf-like processes are attached to the surface of spermatocytes and spermatids. Slender cord-like processes, flat and irregular shaped processes, sucker-like processes and club-like processes are observated in the middle and apical portion of seminiferous epithelium. The sheet-like processes rest upon more than one-thirds of the surface of each spermatogonium, spermatocyes and spermatids located in the proximity of the Sertoli cell. All Sertoli processes are originated from Sertoli cell column. Just before spermiation, the processes which are attached to the head of maturation spermatid are eliminated. Though the mechanism for elimination of residual body is not known, these observations segget that the Sertoli cell process are thought to have a reciprocity with the germ cells.