• Animal cells and systems
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• 제5권4호
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• pp.327-331
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• 2001

There is a critical developmental period during which brain sexual differentiation proceeds irreversibly under the influence of gonadal hormone. Recently, kinesin superfamily-associated protein 3 (KAP3) gene expressed during the 'critical period' of rat brain differentiation was identified by us (Choi and Lee, 1999). KAP3 functions as a microtubule-based motor that transports membranous organelles anterogradely in cells, including neurons (Yamazaki et al., 1996). mRNA level of KAP3 gene markedly increased before the initiation of puberty. Neonatal treatment of estrogen clearly inhibited the prepubertal increase in KAP3 mRNA level (Choi and Lee, 1999). In the present study, we aimed to investigate the effects of polychlorinated biphenyls (PCBs), as endocrine disruptors (EDs) on the expression of KAP3 gene during the 'critical period' of rat brain development. In our data, PCBs significantly decreased the expression of KAP3 gene in the fetal (day 17) and the neonatal (day 6 after birth in) male and female rat brains. The body weight and the breeding ability were significantly decreased in the PCBs-exposed rats compared with the control. These results showed that PCBs affect the transcriptional level of brain sexual differentiation related gene, KAP3, in the fetal and the neonatal rat brains. The maternal exposure to the PCBs may lead to toxic response in embryonic brain sexual differentiation and breeding ability after sexual maturation. This study indicates that KAP3 gene may be useful as a gene marker to analyze the molecular mechanism of toxic response in the animal brain development and sexual maturation exposed to PCBs.

• Journal of Oral Medicine and Pain
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• 제8권1호
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• pp.121-126
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• 1983

This study is conducted with a view to make correct sexual differentiation by the utilization of discriminant functions. For that purpose were randomly sampled out 148 young adults testes, comprising 67 males and 81 females, ranging from 15 through 18 years fo age. Based on the values made available from the measurement of 6 items corresponding to the maxillary cast models, a statistical analysis was made to abstract feasible discriminant functions. The results findings are as follows: 1. The mean value by sex indicates, in all items, higher one in male group than in female group. 2. Through the measurement were defined as singnificant items in sexual differentiation the bucco-lingual dimensions of canine, 1st-molar, 2nd molar, and 1st bimolat width. 3. Derived from the value from measurement items were discriminant functions with the intention of applying them to sexual differentiation, as follows: 1) Y=-25.4112+0.7513BL3+0.3298BL4-0.2854BL5+0.7350BL6-0.3482BL7+0.2893AW (as tested by Method I) 2)Y=-25.0628+0.7737BL3+0.7468BL6-0.3885BL5+0.2951AW(as tested by Method II) BL3 : Bucco-lingual dimension of upper canine BL4 : Bucco-lingual dimension of upper first prmolar BL5 : Bucco-lingual dimension of upper second premolar BL5 : Bucco-lingual dimension of upper first molar BL6 : Bucco-lingual dimension of upper second molar AW : Upper first bimolar width 4. Sexual defferentiation in terms of descriminant functions represented a probility of 74.6%.

• 생명과학회지
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• 제6권3호
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• pp.165-170
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• 1996

The action of phospholipid on the rhodotorucine A(RH.A) acceptance by heterbasidiomyceteous yeast Rhodosporidium toruloides mating type a cells and the effect of medium composition during sexual differentiation were investigated. Activation of trigger peptidase(TPase)was very sensitive to the originated phospholipid from R. toruloides and was more sensitive to phospholipid liposome made up of phospholipi. Phospholopod present on the membrance of mating type a cells consists of phospatidylglycerol(PG), phosphatidylethanolamine(PE), phospatidylcholine(PC), phospatidylinositol(PI), and phosphatidylserine(PS) of 12.9, suprisingly 45.4, 11.0, and 13.9%, respectively. As the result of using C-1 and N-1 mediums which limited C and N sources capable of inhibiting the synthesis of phospholipid, it resulted inhibiting sexual dlfferentiation and production of Rh.A from mating type Acells.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제52차 춘계학술대회 초록집
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• pp.19-37
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• 2007

• 한국발생생물학회지:발생과생식
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• 제4권1호
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• pp.95-100
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• 2000

환경에 방출되어 있는 많은 내분비교란물질들은 사람과 동물의 내분비계에 교란을 일으킬 수 있는 잠재력을 가진다. 뇌의 성분화는 생식소 호르몬 영향하에 비가역적으로 진행되며 흰쥐의 경우 이 시기는 임신말기에서 생후 7∼10일 가량이다. 최근에 본 연구진은 횐쥐의 뇌 성 분화의 결정적인 시기에 발현되는 KAP3유전자를 클로닝하였다 (Choi ＆ Lee, 1999). KAP3의 기능은 신경세포를 포함한 세포에서 aronal tansport를 조절하는 것으로 알려져 있다. 본 연구에서는 흰쥐 뇌 발생의 결정적인 시기에 내분비 교란물질인 Dichlorodiphenyl trichloroethane (DDT)가 KAP3유전자 발현과 성분화에 미치는 영향을 검토하였다. DDT에 노출된 임신 17일된 흰쥐 태아 암컷과 수컷의 뇌에서 KAP3 mRNA의 발현이 증가하였다. 그러나 출생후 DDT에 노출된 흰쥐 암컷과 수컷의 뇌에서는 KAP3 mRNA의 발현은 감소하였다. 또한 태어난 직후 DDT에 노출된 경우 체중이 현저히 감소하였으며 수정율도 DDT에 노출되지 않은 흰쥐에 비하여 크게 낮았다. 이러한 결과는 내분비 교란물질인 DDT가 뇌의 성 분화와 관련된 유전자인 KAP3의 전사에 영향을 미치며, 내분비 교란물질에 노출된 태아의 뇌 분화에서 독성을 보이는 것을 의미한다. 그리고 KAP3유전자는 동물의 신경세포의 발생에 미치는 내분비 교란 물질의 독성을 분자생물학적으로 연구하기 위한 유전자 지표로도 사용 가능하다고 생각된다.

• Ocean and Polar Research
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• 제30권4호
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• pp.401-406
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• 2008

Early gonadal development and sexual differentiation of dark-banded rockfish (Sebastes inermis Cuvier) were followed from parturition to 400 days post parturition (dpp). During this period, average total length (TL) increased from 0.57 to 13.18 cm. Primordial germ cells (PGCs) were first detected at 0.68 cm TL (10 dpp). When fish reached 1.52 cm TL (50 dpp), initial stages of ovarian differentiation were identified by the presence of PGCs containing condensed chromatin and their transformation into meiotic oocytes. At 10.23 cm TL (300 dpp), the ovaries gradually developed into oocytes in the primary yolk stages. Ovary growth was rapid after sex differentiation, but testis tissue continued to multiply without growing until fish reached 6.97 cm TL (200 dpp), after which the production of spermatocytes, spermatogonia, and cyst cells was apparent. Histological analysis of gonadal structure suggested a gonochoristic sexual development pathway. Our analysis of the sex ratio at 400 dpp showed a significantly higher proportion of males.

• Mycobiology
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• 제37권3호
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• pp.171-182
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• 2009

Many aspergilli that belongs to ascomycetes have sexuality. In a homothallic or self-fertile fungus, a number of fruiting bodies or cleistothecia are formed in a thallus grown from a single haploid conidia or ascospores. Genome-sequencing project revealed that two mating genes (MAT) encoding the regulatory proteins that are necessary for controlling partner recognition in heterothallic fungi were conserved in most aspergilli. The MAT gene products in some self-fertile species were not required for recognition of mating partner at pheromone-signaling stage but required at later stages of sexual development. Various environmental factors such as nutritional status, culture conditions and several stresses, influence the decision or progression of sexual reproduction. A large number of genes are expected to be involved in sexual development of Emericella nidulans (anamorph: Aspergillus nidulans), a genetic and biological model organism in aspergilli. The sexual development process can be grouped into several development stages, including the decision of sexual reproductive cycle, mating process, growth of fruiting body, karyogamy followed by meiosis, and sporulation process. Complicated regulatory networks, such as signal transduction pathways and gene expression controls, may work in each stage and stage-to-stage linkages. In this review, the components joining in the regulatory pathways of sexual development, although they constitute only a small part of the whole regulatory networks, are briefly mentioned. Some of them control sexual development positively and some do negatively. Regarding the difficulties for studying sexual differentiation compare to asexual one, recent progresses in molecular genetics of E. nidulans enlarge the boundaries of understanding sexual development in the non-fertile species as well as in fertile fungi.

• Journal of Animal Science and Technology
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• 제48권5호
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• pp.651-662
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• 2006

프탈레이트 에스테르는 플라스틱 가소제로서 이용되며 또한 유제품과 같은 음식에서 미량으로 발견되고, 종종 내분비 교란물질로 의심되고 있다. 본 연구의 목적은 DBP, DINP 또는 DEHA의 주산기 노출이 랫트에 있어 성 성숙 후, 번식기능 특히 뇌의 성분화에 어떤 영향을 끼치는 지에 대해 조사하였다. 이를 수행하기 위해서, 어미에게 식물성 에스트로겐의 함유가 낮은 분말 사료에 다음과 같은 단계적 농도의 DBP (20, 200, 2000, 10000 ppm), DINP (40, 400, 4000, 20000 ppm), DEHA (480, 2400, 12000 ppm)를 혼합한 후, 임신 15일째부터 출생 후, 21일째 (이유기)까지 섭취 시켰고, 성 성숙 후, 혈청 성호르몬 및 성선자극호르몬의 레벨과 교배행동 및 성주기 회귀를 분석하였다. 그 결과, DBP, DINP 또는 DEHA의 주산기 노출에 의한 생후 20~21주째의 암수 랫트에 있어, 성호르몬 및 성선자극호르몬의 레벨뿐만 아니라 암컷의 성주기의 회귀에 대해 어떠한 영향을 주지 않았다. 이것은 시상하부－하수체－성선축의 내분비계를 제어하는 뇌의 성분화에는 이들 화학물질이 영향을 주지 않았다는 사실을 시사한다. 하지만, 수컷의 성행동 특히, 사정 (ejaculation)과 암컷의 로도시스 반응이 억제되는 것이 관찰되었다. 이러한 결과로부터 DBP, DINP 또는 DEHA의 주산기 노출은 성선자극 호르몬의 분비에는 영향을 주지 않지만, 성행동을 제어하는 시상하부의 어떤 영역에 직접적으로 작용할 가능성 즉, 뇌의 성분화에 영향을 끼쳐 성 성숙 후, 성 특이적 행동을 억제시킬 가능성을 시사한다.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.275-280
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• 1999

Male sexual differentiation involves a cascade of events initiated by the presence on the Y chromosome of the of the SRY (sex determining region of Y chromosome) gene, which causes the indifferent gonad to develop into a testis. Hormonal products of the testis, predominantly testosterone and Mullerian inhibiting subtance (MIS), then control the sexual differentiation of the developing fetus. SRY is a transcription factor; however, target genes for its action have yet to be identified, because the DNA recognition sequence for SRY is found in many genes. Therefore the study of intersex disorders is being used to identify other genes active in the pathway of sexual differentiation. Patients with 46,XY gonadal dysgenesis, or Swyer's syndrome, have streak gonads, normal stature, and a sexually infantile phenotype with Mullerian structures present. The inheritance is usually sporadic but can be autosomal dominant or X-linked recessive. Unlike 45,X patients, stigmata of Turner syndrome are rare. As many as 20 to 30% of patients are at risk for malignant gonadal tumor formation and should undergo gonadectomy soon after the diagnosis is made. We have experienced a case of Swyer syndrome which showed a positive SRY gene in peripheral blood and gonad. So we report this case with a brief review of literatures.

• 한국어류학회지
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• 제13권4호
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• pp.248-253
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• 2001

대농갱이, Leiocassis ussuriensis의 생리학적 성전환을 위한 기초적인 연구로 성분화 과정을 조직학적으로 조사하였다. 부화 후 1일째에 중신관과 장 사이의 장간막에 원시생식세포가 나타났으며, 부화 후 5일째의 초기 생식소는 생식융기를 형성하는 원시생식소 구조를 나타내었다. 부화 후 20일째의 생식소는 암, 수로의 분화가 이루어졌는데 정소는 부화 후 20일째에 유사분열 단계의 원시생식세포들이 분포하였으며, 난소에서는 난소를 특징지을 수 있는 entovarian sac의 구조가 난소 중앙부분에 나타났다. 부화 후 40일째 정소에서는 정원세포의수가 점점 증가하였고, 부화 후 50일째 난소에서는 난소강이 더 뚜렸해지며 부화 후 100일째 난소에서는 초기 난모세포가 난소내에 가득 차기 시작하여 기능적 난소의 형태로 분화하였다. 이상의 결과 본 종은 초기 성분화 과정은 자성 단계를 거치지 않고 정소와 난소로 분화되는 분화형 자웅이체였다.