• Applied Microscopy
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• 제27권2호
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• pp.189-196
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• 1997

The ultrastrucures of Xenopus otic vesicle from normal embryo (st. 43) and induced otic vesicle from animal cap assay with Activin A were compared. Activin A was applied to the presumptive ectoderm at various concentrations for three days at $20^{\circ}C$. The results were almost identical to the reference studies, but it was found that the otic vesicle was induced at the concentration of 10 ng/ml in to)v rate. This otic vesicle may be secondarily induced by the neural tissue showed commonly at the concentration of 10 ng/ml. Otoliths were observed as three or four-axis crystaline bodies in the lumen of otic vesicle. In electron micrograph of the normal embryo, two kinds of microvilli were observed on the apical position of hair cells. One was small and common, the other was large-sized and sparsely distributed. In both cell of otic vesicle, mitochondria, golgi apparatus and multivesicular body were rich, so, they showed a lot of similarities in ultrastructure. However, the otolith was not found and microvilli were overexpressed in the otic vesicle induced by Activin A.

• 한국동물학회지
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• 제33권1호
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• pp.94-102
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• 1990

무미 양서류발생중에 근절 예정 부위의 최전방에 나타나는 cranial myotomes인 W, X, Y, Z는 후기 배 발생중에 "reduction"을 나타내는 특이한 체절이다. Cranial Myotome이 programmed autonomous death를 수행하는지 또는 otic vesicle과 같은 주위 조직의 영향에 의해 reduction을 일으키는지에 대한 가설을 검증하기 위해 Xenopus를 재료로 하여 서술적인 면과 조직이식을 통한 발생학적 실험을 수행하였다. 먼저 주위의 otic vesicle을 제거하여도 W, X, Y, Z degeneration에는 아무런 영향도 없었으며 otic vesicle을 체절을 따라 새로운 지역으로 이식하여도 그 부위에서 체절이 사라지는 현상이 유도되지 않았다. 한편, WXYZ형성 예정지역을 trunk somite 부위로 이식한 결과 원래대로 reduction을 나타내었고 truck somite 형성조직을 WXYZ 부위로 이식하여도 원래의 운명대로 분화하였다. 따라서 cranial myotome은 근육이 분절되는 발생시기에 도달하면 주위의 조직에 상관없이 예정된 운명에 따라 자동적으로 소멸되는 것으로 결론지을 수 있다.결론지을 수 있다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.195.1-195
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• 1997

No Abstract, See Full Text

• 생명과학회지
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• 제9권5호
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• pp.504-509
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• 1999

The trend of organogenesis in Xenopus presumptive ectoderm was studied by combined dose of activin A and IGF-1(insulin-like growth factor-1). In reference study of Asashima and his colleagues, the inductive patterns of various organs were reported with activin, the potent mesoderm inducing factor. In present study, the inducing pattern was cleared with combined-dose of concentration 1-100 ng/ml activin A and IGF-1. In addition, the result from single treatment of activin A was compared with former study. As a result, eye was differentiated in 5-20% of explants at 10 and 50 ng/ml concentrative combination of activin A. Otic vesicle was appeared in the entire concentrative combination of IGF-1. Pronephric duct was induced 19-38% of explants at the concentration of activin A 100 ng/ml by adding IGF-1. The comparison of single treatment of activin A was showed some difference in dose-dependent inducing pattern.

• 한국수산과학회지
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• 제48권5호
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• pp.696-703
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• 2015

We investigated the characteristics of embryonic and abnormal organ development in haploid olive flounder, Paralichthys olivaceus, by comparing egg development and histological sections in haploid and diploid individuals. After the mid-blastula transition, abnormal development was observed in haploid fish, including delayed epiboly and malformation of the germ ring and embryonic body. In haploid flounder, Kupffer’s vesicles are irregularly shaped and of variable size compared to diploids. The embryonic body of haploids was shorter and broader than that of diploids and the tail length and size were variable. Most haploid embryos failed to hatch and the few larvae that did, did not survive for more than 6 h. The histological analysis of haploid larvae revealed deformed development in diverse organs, including the eye, otic vesicles, notochord, and neural tube. These results may be related to an abnormality in the axial system of haploid larvae. This study confirmed that the abnormalities of haploid olive flounder were similar to the reported characteristics of haploid syndrome. The abnormalities are caused by delayed epiboly and involution and deformity of Kupffer’s vesicle during egg development.