• Molecules and Cells
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• 제41권8호
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• pp.753-761
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• 2018

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is identified as a signaling adaptor protein that regulates bone metabolism, immunity, and the development of several tissues. Therefore, its functions are closely associated with multiple diseases. TRAF6 is also involved in the regulation of hematopoiesis under steady-state conditions, but the role of TRAF6 in modulating hematopoietic stem and progenitor cells (HSPCs) during the developmental stages remains unknown. Here, we report that the deletion of TRAF6 in hematopoietic lineage cells resulted in the upregulation of HSPCs in the fetal liver at the prenatal period. However, in the early postnatal period, deletion of TRAF6 drastically diminished HSPCs in the bone marrow (BM), with severe defects in BM development and extramedullary hematopoiesis in the spleen being identified. In the analysis of adult HSPCs in a BM reconstitution setting, TRAF6 played no significant role in HSPC homeostasis, albeit it affected the development of T cells. Taken together, our results suggest that the role of TRAF6 in regulating HSPCs is altered in a spatial and temporal manner during the developmental course of mice.

• Molecules and Cells
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• 제41권12호
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• pp.1024-1032
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• 2018

The central mechanisms coordinating growth and sexual maturation are well conserved across invertebrates and vertebrates. Although mutations in the gene encoding makorin RING finger protein 3 (mkrn3) are associated with central precocious puberty in humans, a causal relationship has not been elucidated. Here, we examined the role of mkrn1, a Drosophila ortholog of mammalian makorin genes, in the regulation of developmental timing. Loss of MKRN1 in $mkrn1^{exS}$ prolonged the $3^{rd}$ instar stage and delayed the onset of pupariation, resulting in bigger size pupae. MKRN1 was expressed in the prothoracic gland, where the steroid hormone ecdysone is produced. Furthermore, $mkrn1^{exS}$ larvae exhibited reduced mRNA levels of phantom, which encodes ecdysone-synthesizing enzyme and E74, which is a down-stream target of ecdysone. Collectively, these results indicate that MKRN1 fine-tunes developmental timing and sexual maturation by affecting ecdysone synthesis in Drosophila. Moreover, our study supports the notion that malfunction of makorin gene family member, mkrn3 dysregulates the timing of puberty in mammals.

• BMB Reports
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• 제48권11호
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• pp.599-608
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• 2015

Regeneration, a process of reconstitution of the entire tissue, occurs throughout life in the olfactory epithelium (OE). Regeneration of OE consists of several stages: proliferation of progenitors, cell fate determination between neuronal and non-neuronal lineages, their differentiation and maturation. How the differentiated cell types that comprise the OE are regenerated, is one of the central questions in olfactory developmental neurobiology. The past decade has witnessed considerable progress regarding the regulation of transcription factors (TFs) involved in the remarkable regenerative potential of OE. Here, we review current state of knowledge of the transcriptional regulatory networks that are powerful modulators of the acquisition and maintenance of developmental stages during regeneration in the OE. Advance in our understanding of regeneration will not only shed light on the basic principles of adult plasticity of cell identity, but may also lead to new approaches for using stem cells and reprogramming after injury or degenerative neurological diseases.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2001년도 후기 제12차 학술대회 논문집
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• pp.45-47
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• 2001

생쥐 착상전 초기배아에서 insulin과 tumor necrosis factor $\alpha$ (TNF$\alpha$)에 의한 배아의 형태 발생, 세포증식, apoptosis 및 MAPK활성의 변화를 조사하였다. Insulin에 의해 형태발생 및 포배당 세포수가 증가되었으며 TNF $\alpha$ 처리시 유의하게 감소하였다. TNT$\alpha$ 전처리시 insulin에 의한 발생 및 세포수 증가 촉진효과가 상쇄되었으며 TNF$\alpha$는 배아내 caspase-3의 활성을 증가시켰다. Insulin은 단시간내에 포배에서 mitogen activated protein kinase (MAPK or Erk1/2)의 활성을 증가시켰다. TNF$\alpha$는 포배내 MAPK의 활성을 감소시켰다. Insulin 처리 전 TNF $\alpha$를 전처리한 경우 insulin에 의한 MAPK 활성의 증가가 상쇄되었다. 배발생을 촉진하는 인슐린 신호전달 과정은 MAPK cascade를 경유하며 TNF $\alpha$를 경유한 신호전달과 Crosstalk이 존재하는 것으로 사료된다.

• 한국동물생명공학회지
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• 제35권1호
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• pp.2-11
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• 2020

Assisted reproductive technologies (ART) merely depend on improving the oocyte maturation and their developmental competence to produce good quality embryos. Oocyte maturation passes through long and complex molecular steps starts from the early embryonic life and ends with sperm fertilization. Oocyte developmental competence can be attained by improving the nuclear and cytoplasmic mechanisms together with some epigenetic maturation. In this review, we highlight the cornerstones of oocyte maturation on both nuclear and cytoplasmic levels. Interfering or supporting these molecular mechanisms would help in the development of novel regulating agents for reproductive performance of humans and livestock species.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제8권2호
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• pp.207-216
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• 1997

본 연구는 반응성 애착장애(reactive attachment disorder：향후 RAD라 칭함)집단과 발달성 언어장애(developmental language disorder：향후 DLD라 칭함)집단을 대상으로 외관상 유사한 사회성 문제를 지니고 있으나, 타인과의 사회적 접촉의 시도라는 좀 더 근본적인 의사소통의 의도에서는 집단간에 어떤 차이를 보이는지 알아보기 위해 생활 연령과 언어 연령으로 두 집단을 짝지어 의사소통 의도의 빈도와 주로 사용하는 의사소통 의도의 유형 및 발달 단계를 비교하였다. 그 결과는 DLD아동의 의도 표현 방법이 RAD아동보다 세련되고 정교화 되었음을 보여 주었으며, DLD아동이 RAD아동보다 의사소통하려는 의도를 더 많이 가지고 있음을 나타냈다. 그리고 두집단이 사용하는 의사소통 의도의 내용을 살펴보았더니, DLD아동은 사회적 상호작용>공유적 주의>행동 통제의 순으로, RAD아동은 행동 통제>사회적 상호작용>공유적 주의의 순으로 의사소통하려는 의도를 나타냄으로써, 주로 사용하는 의도의 내용 범주간에도 두 집단간에 차이를 보였다. 또한, 사용한 의사소통 의도의 다양성 비교에서도 총 12가지의 의사소통 의도에서 DLD아동이 RAD아동보다 더 다양한 수의 의사소통 의도를 나타냈다. 이들 결과를 종합해 볼 때, DLD아동보다는 RAD아동에게서 의사소통의도로 잰 사회적 결함의 심각성이 더 드러났음을 알 수 있다.

• Journal of Photoscience
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• 제9권2호
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• pp.94-97
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• 2002

Light is one of the most important environmental factors that influence plant growth and development. It does not function independently but exerts its role through coordinated interactions with intrinsic developmental programs, such as hormonal regulation. One typical example is hypocotyl growth in which light signals are modulated through growth hormones. However, the underlying molecular mechanisms are largely unknown. We demonstrated that brassinosteroids play an important role in the light signal transduction in etiolated hypocotyl growth. A light-responsive Ras-like G-protein, Pra2 from pea, physically and functionally interacts with a cytochrome P450 that specifically catalyzes C-2 hydroxylation in brassinosteroid biosynthesis. The cytochrome P450 expression, along with Pra2, is induced in the dark and predominantly localized in the rapidly elongating zone of etiolated pea epicotyls. Transgenic plants with a reduced level of Pra2 exhibit a dark-specific dwarfism, which is completely rescued by brassinosteroid application. On the contrary, overexpression of the cytochrome P450 results in enhanced hypocotyl growth even in the light, which phenocopies the etiolated hypocotyl growth. It is therefore envisioned that Pra2 is a molecular switch that mediates the crosstalk between light and brassinosteroids in the etiolation process.

• 아동학회지
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• 제22권3호
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• pp.31-48
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• 2001

This study was designed to examine various patterns of developmental change in children's recall, strategic behaviors, and meta-memory with a sort-recall task in relation to utilization deficiencies. Memory tasks consisting of 18 pictures were presented individually to 48 seven-year-old children in each of 7 sessions. Sessions 1 and 2 were baseline; Sessions 3 and 4 were for strategy training, including the organization group, the self-regulation group, the organization/self-regulation group and control group. Sessions 5, 6, and 7 were unprompted tests of strategy maintenance. Results showed significant differences between the 4 groups in their recall, strategy repertories and strategy evaluation. Findings were discussed in terms of the analysis of memory strategy and memory development.

• 한국습지학회지
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• 제2권1호
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• pp.11-17
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• 2000

The natural ecology of our coastal zone has been well preserved because of the designation of Han-Ryea national sea park. However, recently, it is being threatened by the frequent request of district regulation of national park and relaxation of green belt, etc. And also, with the reclamation of the foreshore by the development of industrial complex and tourism resource cultivation on a large scale, development pressure for natural coast is increasing. For that reason, preservation of the ecology, organized management and investigation is needed for the islands which scenery is beautiful and rare animals and plants inhabit. And also, it is worried that major habitats of migrants are diminishing because of the district regulation of national park, relaxation of green belt zone and construction of coastal streets. Therefore. on the basis of the through environmental impact assessment, only the business which are aimed at the preservation and restoration of the natural coast should be admitted and the act of eroding must be restricted.

• Asian-Australasian Journal of Animal Sciences
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• 제23권12호
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• pp.1668-1676
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• 2010

The somatotropic axis plays a key role in proliferation and differentiation of avian organs during both pre- and posthatching periods. This review discusses the complexity of regulation of the endocrine system for chicken development and growth by growth hormone (GH), insulin-like growth factor (IGF), and IGF binding protein (IGFBP). In addition, the thyrotropic axis, including thyrotropin-releasing hormone (TRH) and thyroid hormones ($T_4$ and $T_3$), is also involved in the GH-secreting pattern. In mammals, IGFI and -II are always sequestered in a 150 kDa non-covalent ternary complex. This complex consists of one molecule each of IGF-I or IGF-II, IGFBP-3 or IGFBP-5 and an acid labile subunit (ALS). Chick ALS is identified in different strains for the first time, and further investigation of the expression of ALS on developmental stage and ALS effect on IGF bioavailability may be addressed in the future.