ISSN : 1225-3480
담수 복족류인 다슬기, Semisulcospira libertina libertina의 난자형성과정 동안 생식세포의 미세구조 변화를 광학현미경과 전자현미경으로 관찰하였다. 난소는 나탑 후방부의 간췌장의 표면에 위치하며, 성숙시기에는 녹색을 나타내었다. 난소는 다수의 난자형성소낭들로 이루어져 있었다. 난자형성과정은 5단계로, 난원세포기, 난황형성전기, 난황형성개시기, 난황형성활성기, 성숙기로 구분하였다. 난원세포는 직경 <TEX>$4-6\;{\mu}m$</TEX>의 원형으로 커다란 핵을 가진다. 난황형성전기의 난모세포는 직경이 약 <TEX>$20\;{\mu}m$</TEX>이며, H-E 염색에서 세포질은 호염기성을 나타냈다. 난황형성개시기의 난모세포는 직경 <TEX>$60-80\;{\mu}m$</TEX> 내외로 세포질에는 전자밀도가 낮은 난황과립들을 가지며, 난병에 의하여 난자형성소낭에 연결되어 있었다. 난황형성 활성기의 난모세포는 직경 <TEX>$100-120\;{\mu}m$</TEX>로 난황과립의 전자밀도, 크기, 양이 증가하였으며, 세포질에는 골지체, 미토콘드리아, 조면소포체들이 발달하였다. 성숙기 난모세포의 세포질 대부분은 전자밀도가 높은 단백질성의 난황과립들로 채워져 있었으며, 난막에서는 길이 약 <TEX>$1.1\;{\mu}m$</TEX>의 미세융모가 관찰되었다.
The ultrastructural changes in germ cells during oogenesis of the melania snail, Semisulcospira libertina libertina have been investigated by light and electron microscopy. The ovary is located on the surface of the hepatopancreas in the spiral posterior region. The ovary exhibited greenish color in the gonadal mature season. The ovary was composed of a number of oogenic follicles. Oogenesis was divided into five stages with histological features: (1) oogonia, (2) previtellogenic, (3) initial vitellogenic, (4) active vitellogenic, and (5) mature stages. Oogonia were oval in shape, 4-6 μm in diameter, and had a large nucleus. Previtellogenic oocytes were about 20 μm in diameter and the cytoplasm reacted with hematoxylin in H-E satin. Initial vitellogenic stage, oocytes were 60-80 μm in diameter, and small yolk granules of low electron density are scattered in the cytoplasm. Oocytes in the initial vitellogenic stage were connected with ovarian follicle by egg stalk. Active vitellogenic oocyte were 100-120 μm in diameter. Electron density, size and quantity of yolk granules that are distributed in the cytoplasm have increased from the previous stage. Result of TEM observations, the oocyte contains well-developed Golgi complex, endoplasmic reticula and tubular mitochondria in the cytoplasm. Cytoplasm of mature oocyte was filled with proteinaceous yolk globules of high electron density. In this stage, the length of microvilli in the egg envelope was approximately 1.1 μm.
Amor, M.J., Ramón, M. and Durfort, M. (2004) Ultrastructral studies of oogenesis in Bolinus brandaris (Gastropoda: Muricidae). Scientia Marina, 68: 343-353.
Beams, H.W. and Sekhon, S.S. (1966) Electron microscope studies on the oocyte of the fresh-water mussel (Anodonta), with special reference to the stalk and mechanism of yolk deposition. Journal of Morphology, 119: 477-501.
Chang, Y.J. and Lee, T.Y. (1982) Gametogenesis and reproductive cycle of the cockle, Fulvia mutica (Reeve). Bulletin of Korean Fisheries Society, 15: 241-253. [in Korean]
Chang, Y.J., Chang, H.J., Min, B.H. and Bang, I.C. (2000) Reproductive cycle of the melania snail, Semisulcospira libertina libertina. Development and Reproduction, 4: 175-180.
Chung, E.Y. and Kim, Y.M. (2000) Ultrastructural study of germ cell development and sexual maturation of the hard clam, Meretrix lusoria (Bivalvia: Veneridae), on the west coast of Korea. Journal of Medical and Applied Malacology, 10: 181-202.
Chung, E.Y. and Ryou, D.K. (2000) Gametogenesis and sexual maturation of the surf clam Mactra veneriformis on the west coast of Korea. Malacologia, 42: 149-163.
Chung, E.Y., Kim, S.Y., Park, K.H. and Park, G.M. (2002) Sexual maturation, spawning, and deposition of the egg capsules of the female purple shell, Rapana venosa (Gastropoda: Muricidae). Malacologia, 44: 241-257.
Eckelbarger, K.J. and Young, C.M. (1997) Ultrastructure of the ovary and oogenesis in the methane-seep mollusc Bathynerita naticoidea (Gastropoda: Neritidae) from the Louisiana slope. Invertebrate Biology, 116(4): 299-312.
Habe, S. and Itagake, H. (1978) Ecological study on the freshwater snail, Semisulcospira libertina (G.). Venus, 37: 77-82.
Hodgson, A.N. and Eckelbarger, K.J. (2000) Ultrastructure of the ovary and oogenesis in six species of patellid limpets (Gastropoda: Patellogastropoda) from South Africa. Invertebrate Biology, 119: 265-277.
Jong-Brink, M. and Geraerts, W.P.M. (1982) Oogenesis in gastropods. Malacologia, 22: 145-149.
Jung, G.K., Park, J.J., Ju, S.M., Jin, Y.G. and Lee, J.S. (2007) Ovarian structure and oogenesis of the spiny top shell, Batillus cornutus (Lightfoot, 1786) (Gastropoda: Turbinidae). The Korean Journal of Malacology, 23: 209-216. [in Korean]
Kim, B.H., Choi, K.S. and Lee, Y.D. (1996) Study on the reproductive cycle of the top shell, Chlorostoma argrostoma turbinata. Bulletin of Marine Research Institute Cheju National University, 20: 9-15. [in Korean]
Koike, K., Kuniyoshi, S., Furuse, K., Umezawa, N., Masuda, A. and Nishiwaki, S. (1992) Seasonal changes in gametogenesis and embryo composition in the brood pouch of Semisulcospira libertina. Venus, 51: 279-294.
Lee, J.H. (1999) Gametogenesis and reproductive cycle of the rock shell, Reishia (Thais) clavigera (Neogastropoda: Muricidae), on the west coast of Korea. Korean Journal of Biological Society, 3: 375-383.
Lee, J.H. (2000) Sexual maturation of the turban shell, Lunella coronata coreensis (Gastropoda: Turbinidae), on the west coast of Korea. Journal of the Korean Fisheries Society, 33: 533-540. [in Korean]
Lee, J.H. (2001) Gonadal development and reproductive cycle of the top shell, Omphalius rusticus (Gastropoda: Trochidae). Korean Journal of Biological Society, 5: 37-44.
Lee, J.H. (2002) Gonadal development and reproductive cycle of the sand snail, Umbonium thomasi. Journal of the Korean Fisheries Society, 35: 702-708. [in Korean]
Lee, J.Y., Chang, Y.J. and Chang, Y.J. (2003) Ultrastructure of germ cell during the gametogenesis in surf clam, Spisula sachalinensis. Journal of the Korean Fisheries Society, 36: 157-162. [in Korean]
Lee, J.Y., Park, Y.J. and Chang, Y.J. (1999) Gonadal development and reproductive cycle of Gomphina melanaegis (Bivalvia: Veneridae). Journal of the Korean Fisheries Society, 32: 198-203. [in Korean]
Lee, T.Y. (1974) Gametogenesis and reproductive cycle of abalones. Publication of the Marine Laboratory from Pusan Fisheries College, 7: 21-50. [in Korean]
Nakano, D. and Izawa, K. (1996) Reproductive biology of Semisulcospira libertina in Iga Basin, Mie Prefecture. Venus, 55: 235-241.
Nakano, D. and Nishiwaki, S. (1989) Anatomical and histological studies on the reproductive system of Semisulcospira libertina (Prosobranchia: Pleuroceridae). Venus, 48: 263-273.
NFRDI (National Fisheries Research and Development Institute). (1999) Commercial Molluscs from the Freshwater and Continental Shelf in Korea. pp. 197. Gudeok, Busan. [in Korean]
Park, J.J., Lee, J.Y., Lee, J.S. and Chang, Y.J. (2003) Gonadal development and gametogenic cycle of the equilateral venus, Gomphina veneriformis (Bivalvia: Veneridae). Journal of the Korean Fisheries Society, 36: 352-357. [in Korean]
Riehl, R. (1978) Light and electron microscopical investigations on the oocytes of the freshwater teleost fishes Noemacheillus barbatulus L. and Gobio gobio L. (Pisces, Teleostei). Zoologischer Anzeiger, 201: 199-219.
Selman, K. and Wallace, R.A. (1982) Oocyte growth in the sheepshead minnow: uptake of exogenous proteins by vitellogenic oocytes. Tissue and Cell, 14: 555-571.
Selman, K. and Wallace, R.A. (1983) Oogenesis in Fundulus heteroclitus III. Vitellogenesis. Journal of Experimental Zoology, 226: 441-457.
Selman, K. and Wallace, R.A. (1986) Gametogenesis in Fundulus heteroclitus. American Zoologist, 26: 173-192.
Wallace, R.A. and Selmen, K. (1981) Cellular and dynamic aspects of oocyte growth in teleosts. American Zoologist, 21: 325-343.
