• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.41-41
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• 2001

Chromatin configuration and microtubule assembly were determined in porcine maturing and activated oocytes following intracytoplasmic sperm injection. Microtubule localization was confirmed using a mouse monoclonal antibody to $\alpha$-tubulin and detected using a fluorescent labeled goat anti-mouse secondary antibody. DNA was stained with propidium iodide. The image of microtubules and chromatin was captured using laser scanning confocal microscope. In germinal vesicle stage oocyte, sperm chromatin remained condensation and sperm derived microtubules were not observed at 8 to 12 h after sperm injection. At 24 h after injection, the sperm nucleus developed to the metaphase chromatin along the metaphase structure of female nucleus. In some metaphase I stage oocytes, sperm chromatin decondensed at 8 h to 12 h after injection, sperm aster was seen soon after sperm injection. At 24 h after sperm injection into metaphase I stage oocyte, male chromatin developed to the metaphase chromatin while female chromatin extruded first polar body and formed the metaphase chromatin. At 12 to 15 h after sperm injection into preactivated oocytes, condensed sperm nucleus was located in close proximity of female pronucleus. However, the condensed nucleus did not fuse with female pronucleus. In preactivated ocytes, injected sperm remained condensation, a few sperm organized small microtubular aster. Instead, maternal derived microtubules were organized near the female chromatin, which seem to move condensed male chromatin near to the female pronucleus. These results suggest that sperm nuclear decondensing activity and nucleation activity of centrosome during fertilization are cell cycle dependent. In absence of male functional centrosome, female origin centrosome takes over the role of microtubule nucleation for nuclear movement.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.18-18
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• 2001

Despite of importance of integrated events of nucleus and microtubule remodeling in nuclear transferred embryos with somatic cells, little information is available on this subject. In this study we configured chromatin and microtubule organization following somatic cell nuclear transfer in pre- and non-activated bovine oocytes in order to clearify nuclear remodeling process and to demonstrate centrosome inheritance during nuclear transfer. The cumulus-oocyte complexes were collected from slaughterhouse and were matured in vitro for 20 h in TCM 199 supplemented hormone. Matured bovine oocytes were enucleated by aspirating the frist polar body and metaphase chromatin using a beveled pipette. Bovine fibroblast cells were fused into enucleated oocyte by electrical stimulation. Reconstructed oocytes were activated with ionomycine and 6-dimethylaminopurin, and then cultured in CRlaa medium. The organization of nuclear and microtubules were observed using laser-scanning confocal microscopy. At 1 hour after fusion, microtubule aster was seen near the transferred nucleus in most oocytes regardless activation condition. While most of fibroblast nuclei remodeled to premature chromosome condensation (PCC) and to the two masses of chromosome in non-activated oocytes, a few number of fibloblasts went to PCC and multiple pronuclear like structures in activated oocytes. Microtubular spindle was seen around condensed chromosome. Gamma-tubulin was detected in the vicinity of condensed chromosome, suggesting this is a transient spindle. The spindle seperated nucleus into two masses of chromatin which developed to the pronuclear like structures. Two pronuclear like structures were than apposed by microtubular aster and formed one syngamy like nuclear structure at 15 h following nuclear transfer. At 17 to 18 h after fusion, two centrosomes were seen near the nucleus, which nucleates micrtubules for two cell cleavage. While 31% of reconstructed oocytes in non-activated condition developed to morulae and blastocysts, a few reconstructed oocytes in pre-activated condition developed to the blastocyst. These results suggested introduction of foreign centrosome during nuclear transfer, which appeared to give an important role for somatic cell nuclear reprogramming.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.99-99
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• 2001

The acid-labile subunit (ALS) associates with insulin-like growth factor (IGF)-I or -II and IGF binding protein-3 (IGFBP-3) to form a 150-kD complex in the circulation. This complex is thought to regulate the serum IGFs by restricting them in the vascular system and promotes their endocrine actions. Little is known about how ALS binds to IGFBP3, which connects the IGFs to ALS. Xenopus oocyte was utilized to study the function of ALS in assembling IGFs into the ternary complexes. Xenopus oocyte was shown to correctly translate in vitro transcribed mRNAs of ALS and IGFBP3. IGFBP3 and ALS mRNAs were injected in mixture and their products were immunoprecipitated by antisera against ALS and IGFBP3. Contrary to the traditional reports that ALS interacts only with IGF-bound IGFBP3, this study shows that ALS is capable of forming a binary complex with IGFBP3 in the absence of IGF. When cross-linked by disuccinimidyl substrate, band representing ALS-IGFBP3 complex was evident on the PAGE. IGFBP3 movement was monitored according to the distribution between the hemispheres. Following a localized translation in the vegetal hemisphere, IGFBP3 was shown to remain in the vegetal half in the presence of ALS. Different from wild type IGFBP3, however, mutant IGFBP3 freely diffused into the animal half despite the presence of ALS. Taken together, this study suggests that ALS may play an important role in sequestering IGFBP3 polypeptides via the intermolecular aggregation. Studies using this heterologous model will lead to a better understanding of the IGFBP3 and ALS assembling into the ternary structure and circulating IGF system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.219-224
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• 2000

Reproductive biology of the naked-headed goby, Faronigobius gymnauchen was investigated by means of histological methods. The ovary was consisted of several ovarian lamellae and the oogonia originated from the inner surface of the ovarian lamella. The testis was seminiferous tubule One in internal structure. Seminiferous tubule was consisted of many testicular cysts which contained numerous germ cells in a same developmental stage. The size of group maturity was 4.5 cm intotal length. Gonadosomatic index(GSI) of the female and male was the highest in June and July, respectively. Reproductive cycle could be classified into the growing ($January{\~}March$), maturation ($April{\~}May$), ripe and spent (June{\~}July$), and recovery and resting ($August{\~}December$). Oocyte development was group-synchronous, and yolk nucleus was observed in the early growing oocyte.

• Applied Microscopy
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• v.20 no.2
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• pp.117-126
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• 1990

Structural changes of the vitelline envelopes during oogenesis of a polychaete, Nectoneanthes oxypoda, were examined with a scanning electron micrscope. Oocytes grow in the same coelomic fluid to the final stage, but the surface appears to change in the structure during oogenesis. Projections, which were identified to be microvilli, change in shape, number and size. Short microvilli, which cover the surface of oocyte of $33{\mu}m$ diameter densely, grow in length, reaching a maximum at the stage of $73{\mu}m$. The number of microvilli increases with the stages of oogenesis, reaching a plateau at the stage of $82{\mu}m$. The observations suggest that control of material transport including yolk precursor proteins may be correlated with the structural changes in the microvilli.

• The Korean Journal of Zoology
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• v.38 no.2
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• pp.212-219
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• 1995

Through the histolosical observation of ovary in the nine species of the genus Cobitis, we found that specific adhesive membranes were attached to the outer zone radials during the vitellosenesis. These adhesive membranes could be classified into four forms as follows: 1) granular form of Colitis lutheri, C. striate, and C. sinensis, 2) villous form of C. longicorpus, C. konensis koreensis, C. k. pumilus, and C. granoei, 3) saw-like form of C. rotundicaudata, and 4) filamentous form of C. chou. The various forms of adhesive membrane of egg in the cobitid fishes are showed a species specificitv with reference to their habitats and spawning property.

• The Korean Journal of Zoology
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• v.39 no.4
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• pp.419-425
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• 1996

The five spedes of genus Iksookimia from Korea were investigated by electron microscopes to clarify the adhesive membranes on zona radiata. In the late vitellogenic stage the adhesive membranes could be classified into three form as follows: 1) villous form of Iksookimia koreensis, I pumila, and I. hugowolfeldi, 2) cotton-shaped form of I. longicorpus, and 3) vine-shaped form of I. choii. And although I. koreensis, I pumila, and I. hugowolfeldi possessed the same villous form, It was evident that fine structure of the zona radiata varied according to spedes. The adhesive membranes and fine structures of zona radiata in Iksookimla showed a species specificity related to closely their habitats and spawning properties.

• Development and Reproduction
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• v.25 no.3
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• pp.123-131
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• 2021

We report on the gonadal structure abnormality and intersexuality found from a survey regarding the reproductive potential of the rock bream, Oplegnathus fasciatus, along the southern coast of Korea. In total, 448 samples were collected for histological analysis (total length 27.5±6.8 cm; total weight 522.9±385.6 g). The sex ratio (F:M) was 1:0.46 (n=307:141), with 68.5% being females. The frequency of oocyte atresia and ovarian neoplasm in the females was 85.3% and 21.5%, respectively, and the frequency of testicular lobule and cyst deformation and testicular neoplasm in the males was 73.1% and 37.6%, respectively. The scale formation in the ovary and testis was approximately 2.0% for both sexes. The intersexuality was 42.2%, with the intersexuality among females being 49.5%, which was significantly higher than that of males (26.2%). Such findings indicate a negative impact on the reproductive output of the rock bream along the southern coast of Korea; however, a more detailed study is required to ascertain accurate causes.

• Korean Journal of Ichthyology
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• v.26 no.3
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• pp.179-184
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• 2014

A histological study on the egg envelope and oogenesis of Gobiobotia brevibarba (Pisces, Cyprinidae) was carried out by a light microscope and a scanning electron microscope. Various developmental cells appeared in the ovary caught during May 2014, spawning season. For the relative area of oocyte, the ovary consisted of mature stage (74.5%), a vitellogenic stage (yolk granule stage, 16.6% and yolk vesicle stage, 6.6%) and previtellogenic stage (perinucleolus stage 2.2%), which means its spawning season. The cytoplasm of the perinucleolus oocyte is acidic and many nucleoli are located at the inner side of the nuclear membrane. The yolk vesicles, an early vitellogenic stage, has a follicular layer and a zona radiata clearly. Numerous villi, called an egg envelope, begin to form on the zona radiata. The yolk granules, an another vitellogenic stage, proceeds and they show a strong eosinophilic nature. Such yolk granules appeared between the yolk vesicles occupying most cytoplasm, and as the stage proceeds, there are some yolk masses fused with each other. Egg envelope is covered with plenty of villi ($2{\sim}3{\mu}m$ in the length) over the entire egg surface.

• Applied Microscopy
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• v.33 no.2
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• pp.105-116
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• 2003

In Vitro fertilization of U. unicinctus eggs observed by immunofluorescence and electron microscopes revealed an overview of the meiotic pattern of the tide animals. The eggs have been fertilized early at germinal vesicle stage, followed by germinal vesicle break down (GVBD), but pre-mitotic aster like structure could not be resolved by the methods employed in this work. The meiotic features, such as rotation-shift movement of spindle fibers, behavior of spermatozoonmonaster in the egg cytoplasm and active spindle fiber of the 1st polar body, have been observed. The antitubulin-FITC fluorescence show the 2nd meiotic apparatus appeared firstly parallel to the tangential line of the oolemma, proceeding the meiosis, its bipolarity is rotated and shifted towards the oolemma. The polar bodysite of the oolemma was not amorphous, but active in a sense of anti-tubulin-FITC reactions during the extrusions of the polar bodies. The immunofluorescence reactions of the spermatozoon centriole appeared at a later stage of the 2nd meiosis. During the time periods, the fertilized spermatozoon resided in the egg cytoplasm. Activating the centrioles, spermatozoon approaches towards the chromosomal materials of the 2nd oocyte. This suggests that spermatozoon centrioles initiate and play a roll to fuse male and female pronuclei.