• KSBB Journal
• /
• 제18권4호
• /
• pp.329-334
• /
• 2003

Insulin-like growth factor-I (IGF-I) 유전자의 발현은 사람 및 쥐에서 두 개의 promoters (P1과 P2)로부터의 전사와 alternative RNA splicing 및 differential RNA polyadenylation과 같은 복잡한 기전들에 의하여 조절되는데 조직에 따라 성장호르몬을 포함한 여러 요소들이 관여하는 것으로 알려져 있다. 또한 사람의 IGF-I 유전자 exon 1의 upstream에 존재하는 P1에 hepatocyte nuclear factor l$\alpha$와 CAAT/enhancer-binding protein (C/EBP) isoform 들이 결합하여 조직 및 발달단계 특이한 발현에 중요한 역할을 할 것으로 제안되었지만, exon 1의 downstream sequence가 IGF-I 유전자의 조직 특이적 발현을 조절하는 지에 대하여는 연구되어 있지 않다. 연령이 다른 쥐의 간 및 뇌 조직에서 total RNA를 분리하고 solution hybridization/RNase protection 방법으로 분석하여 IGF-I 유전자의 발현이 태어난 후 간 조직에서는 점차적으로 증가하였지만 뇌조직에서는 감소하여 발달단계에 따라 조직 특이하게 발현되는 것을 확인하였다. IGF-I exon 1의 주요한 전사 개시점으로부터 아래쪽에 존재하는 C/EBP 결합부위를 포함하고 있는 cis-acting element에 해당하는 oligonucleotide들과 간 및 뇌조직에서 분리한 핵단백질들을 이용하여 DNA-결합 활성을 가진 분자량이 다른 C/EBP$\alpha$나 C/EBP$\beta$ 단백질들을 확인하였으며 southwestern 및 western immnoblotting 분석을 하여 간 조직의 핵 추출물에서는 42$^{C}$EBP$\alpha$/, 와 p38$^{C}$EBP$\alpha$/, p35$^{C}$EBP$\alpha$/, p38$^{C}$EBP$\beta$/, 그리고 p35$^{C}$EBP$\beta$/가 IGF-I exon 1 oligonucleotide와 복합체를 형성하고 뇌 조직에서는 p42$^{C}$EBP$\alpha$과 p38$^{C}$EBP$\beta$가 복합체 형성에 관여하는 것으로 나타났다. 이러한 결과들은 FRE-C/EBP isoform 복합체 형성이 IGF-I 유전자 발현의 조직 특이적 조절에 중요한 역할을 할 것으로 제안한다.할을 할 것으로 제안한다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권4호
• /
• pp.466-470
• /
• 2007

CCAAT/enhancer binding protein ${\alpha}$($C/EBP{\alpha}$) plays an important role in lipid deposition and adipocyte differentiation. In order to find genetic markers to improve the meat quality of Korean cattle, the bovine $C/EBP{\alpha}$ gene was chosen as a candidate gene to investigate its association with carcass and meat quality traits in Korean cattle. A single nucleotide polymorphism (SNP) was identified at position 271 (A/C substitution) of coding region in the $C/EBP{\alpha}$ gene. A PCR-RFLP procedure with restriction enzyme SmaI was developed for determining the marker genotypes. The frequencies of alleles C and A and were 0.374 and 0.626, respectively. The genotype frequencies for CC, AC and AA were 12.9, 49.0 and 38.1%, respectively, in Korean cattle population. The frequencies of genotype were in agreement with Hardy-Weinberg equilibrium. Association analysis indicated that the gene-specific SNP marker of $C/EBP{\alpha}$ showed a significant association with marbling score (p<0.05). The animals with AA genotype had higher marbling score than those with the AC or CC genotype. Although further studies are needed to validate our results, the $C/EBP{\alpha}$ gene could be useful as a genetic marker for carcass and meat quality traits in Korean cattle.

• Journal of Animal Science and Technology
• /
• 제46권6호
• /
• pp.909-916
• /
• 2004

CCAAT/enhancer binding protein(C/EBP)는 지방전구세포의 분화과정에서 말현하는 전사인자군에 속한다. 이러한 C/EBP 중에서 C/EBP $\alpha$ 는 지방세포의 분화와 지방침착에 있어 중요한 역할을 수행허는 것으로 알려져 있다. 본 연구에서는 한우 C/EBP$\alpha$ 유전자를 분리 동정하고 그 발현을 조사하였다. 한우 C/EBP$\alpha$ 유전자는 1059bp의 open reading frame으로 구성되어 있으며 353개의 아미노산을 암호화하고 있었다. 그리고 한우 C/EBP $\alpha$ 아미노산을 다른 종과 비교하였을 때 매우 높은 상동성을 나타내었다. Northern blotting 분석에 의하여 12개월 한우에 있어서 C/EBP$\alpha$ mRNA의 분석을 실시한 결과 지방조직에서 가장 높은 말현을 나타내었으며 대장과 폐에서 매우 낮은 말현을 확인할수 있었다. 또한 12개월26개월 30개월 한우 의 등심과 지방에 있어서 C/EBP$\alpha$ 유전자의 발현을 real-time RT-PCR로 분석한 결과 등심 에서는 26개월에 서 가장 높은 발현을 보였으며 지방에서는 12개월과 26개월에 서 높은 발현을 나타내었다.

• 대한의생명과학회지
• /
• 제14권3호
• /
• pp.131-137
• /
• 2008

Adipogenesis is a complex sequence of events that culminates in the differentiation of fibroblast-like preadipocytes into specialized lipid-filled adipocytes and also involves a cascade of expression of many transcription factors such as peroxisome proliferator-activated receptor ${\gamma}(PPAR{\gamma})$ and CCAAT/enhancer-binding proteins (C/EBPs). $PPAR{\gamma}$ and C/EBPs transcriptionally transactivate adipocyte specific genes, including fatty acid transport protein (FAT/CD36) and leptin. To determine whether $17{\beta}$-estradiol modulates $C/EBP{\alpha}$ actions on adipogenesis in high fat diet-fed female ovariectomized (OVX) C57BL/6 mice, mice were treated with $17{\beta}$-estradiol for 7 days and the effects of $17{\beta}$-estradiol on adipose tissue mass and expression of adipocyte specific gene as well as $C/EBP{\alpha}$ were measured. Compared to vehicle-treated OVX control mice, OVX mice treated with $17{\beta}$-estradiol for 7 days had lower adipose tissue weights that were similar to weights in high fat diet-fed sham-operated (Sham) mice. OVX mice showed the increased expression of $C/EBP{\alpha}$ mRNA compared with Sham mice. However, $17{\beta}$-estradiol treatment in OVX mice inhibited OVX induced-$C/EBP{\alpha}$ activation, indicating that $17{\beta}$-estradiol may act as an inhibitor of $C/EBP{\alpha}$ action. Moreover, $17{\beta}$-estradiol decreased mRNA levels of adipocyte marker genes, such as lipoprotein lipase, FAT/CD36 and leptin, to levels in Sham mice. These results suggest that down-regulation of adipogenesis by $17{\beta}$-estradiol may be due to reduced adipose $C/EBP{\alpha}$ activities in female OVX C57BL/6 mice.

• 생명과학회지
• /
• 제22권10호
• /
• pp.1316-1323
• /
• 2012

본 연구는 한우유래 myoblast에서 지방세포분화 유도 전사인자들을 과발현시켜 지방세포로의 교차분화를 유도하기 위하여 실시하였다. 한우 유래 satellite cell을 배양한 후 adipogenic transcription factor인 $PPAR{\gamma}$, C/$EBP{\alpha}$, SREBP1c, KLF5등을 단독 또는 co-transfection을 실시하여 세포에 과발현을 유도하였다. 이들 세포들은 adipogenic differentiation medium에서 2일간 배양한 후growth medium에서 8일간 추가로 배양하였다. 지방세포로의 교차분화 유무는 Oil-red O염색과 지방세포 마커 유전자들의 발현으로 확인하였다. $PPAR{\gamma}$과 C/$EBP{\alpha}$를 각각 단독으로 과발현을 유도한 경우myoblast에서 지방세포로의 교차분화를 유도하기에는 충분하지 못하였다. 그러나 $PPAR{\gamma}$와 C/$EBP{\alpha}$을 co-transfection을 실시한 경우 지방세포로의 교차분화가 유도되었고, 세포내지방구형성, 지방세포 마커유전자의 발현, 근세포 마커유전자의 발현 감소 등이 확인되었다. KLF5 와 $PPAR{\gamma}$를 동시에 과발현할 경우 지방세포로의 교차분화를 볼 수 있었지만 KLF단독의 경우는 교차분화를 유도하지 못하였다. 할성형SREBP1c (tSREBP1c)의 경우, 단독으로 myoblast에 과발현을 처리한 경우만으로 지방세포로의 교차분화를 유도할 수 있었다. 이들 결과는 한우유래 satellite cell을 이용하여 지방세포분화 전사인자를 단독 혹은 조합하여 이들 세포에 과발현 시킬 경우 지방세포로의 교차분화를 유도할 수 있음을 보여 주었다.

• Preventive Nutrition and Food Science
• /
• 제13권2호
• /
• pp.66-70
• /
• 2008

In order to develop a functionally improved kochujang with antiobesity effects, garlic-added kochujang was prepared with freeze-dried garlic powder and followed by fermentation for 60 days at $30^{\circ}C$. Antiobesity effect of the garlic-added kochujang was investigated by measuring the leptin secretions and mRNA expression levels of obesity-related gene such as TNF${\alpha}$, PPAR${\gamma}$, C/EBP${\alpha}$, and SREBP1c, in cultured 3T3-L1 adipocytes. Fermentation of garlic-added kochujang led to decreased levels of leptin secretions and reduced the mRNA expression levels of TNF${\alpha}$, PPAR${\gamma}$, C/EBP${\alpha}$, and SREBP1c in the 3T3-L1 adipocytes. Accordingly, these results suggest that the addition of garlic to kochujang has a potential as a valuable functional food for controlling obesity.

• Food Science and Biotechnology
• /
• 제16권2호
• /
• pp.212-217
• /
• 2007

Fucoidan (fucan sulfate) is a fucose-containing sulfated polysaccharide from brown algae such as Fucus vesiculosus, Ecklonia kurome, and Cladosiphon okamuranus. The aim of this study was to investigate the effect of fucoidan on the expression of diabetes-related genes in mouse cell line 3T3-L1. 3T3-L1 adipocytes were cultured for 48 hr with or without fucoidan (10, 100, and 500 ppm) on a 60 mm dish. Reverse transcription polymerase chain reaction (RT-PCR) was used for measurement of peroxisome proliferators activated receptor ${\gamma}\;(PPAR{\gamma})$, CCAAT/enhancer binding protein ${\alpha}\;(C/EBP{\gamma})$, and glucose transporter 4 (GLUT4) RT-PCR analysis revealed that expression level of GLUT4, $PPAR{\gamma}$, and $C/EBP{\alpha}$ mRNAs increased with fucoidan treatment from 10 to 500 ppm in a dose-dependent manner. Fucoidan appears to enhance insulin sensitivity by increasing the expression level of diabetes-related genes in 3T3-L1 adipocytes. Therefore, fucoidan is potentially useful as a natural therapeutic material for hyperglycemia in type II diabetes patients.

• 한국식품영양과학회지
• /
• 제41권2호
• /
• pp.161-167
• /
• 2012

본 연구에서는 3T3-L1 지방전구세포를 이용하여 용아초 에틸아세테이트 추출물의 항비만 활성을 확인하고자 하였다. 용아초 에틸아세테이트 추출물에 의한 지방세포 분화 및 adipogenesis 저해 활성을 확인하기 위해 추출물을 3T3-L1 지방전구세포에 분화를 유도하면서 농도별(50, 100 ${\mu}g/mL$)로 처리하였고, 그 결과 용아초 에틸아세테이트 추출물은 지방세포의 분화를 억제시켰다. 이 같은 활성에 대한 기전을 확인하기 위해 PPAR${\gamma}$ 전사활성과 지방세포 분화에 관여하는 유전자들의 활성을 확인해 보았다. 실험 결과 용아초 에틸아세테이트 추출물은 PPAR${\gamma}$ 전사 활성을 억제시켰고 PPAR${\gamma}$ 및 C/EBP${\alpha}$의 mRNA 발현을 농도 의존적으로 감소시켰으며 지방세포 분화에 관여하는 adipokine들의 발현을 조절하는 것으로 나타났다. 따라서 용아초 에틸아세테이트 추출물의 항비만 효과는 지방 생성의 주요 전사인자인 PPAR${\gamma}$와 C/EBP${\alpha}$의 유전자 발현조절을 통해 지방 분화 억제 및 지방 축적을 효과적으로 감소시키는 것으로 보이며, 효과가 있는 농도가 100 ${\mu}g/mL$로 천연물질로써 비교적 낮은 농도에서 효과가 나타나는 것으로 보아 항비만 소재로의 개발 가능성이 있을 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권10호
• /
• pp.1420-1428
• /
• 2009

In this study we cloned and characterized a novel lipid-accumulating gene, the oxidized low-density lipoprotein receptor 1 (OLR1), which is associated with lipogenesis. We analyzed the gene structure and detected the mRNA transcriptional expression levels in pig adipose tissues at different months of age (MA) and in different economic types (lean type and obese type) using real-time fluorescence quantitative PCR. OLR1 expression profile in different tissues of pig was analyzed. Finally, we studied the correlation between OLR1 and lipid metabolism related genes including peroxisome proliferator-activated $receptor{\gamma}2$ ($PPAR{\gamma}2$), fatty acid synthetase (FAS), triacylglycerol hydrolase (TGH), CAAT/enhancer binding protein $\alpha$ ($C/EBP{\alpha}$) and sterol regulatory element binding protein-1c (SREBP-1c). Results indicated that the OLR1 gene of the pig exhibited the highest homology with the cattle (84%), and the lowest with the mouse (27%). The signal peptide located from amino acid 38 to 60 and the domain from amino acid 144 to 256 were shared by the C-type lectin family. The expression level of OLR1 in pig lung was exceedingly higher than other tested tissues (p<0.01). In pig adipose tissue, the expression level of OLR1 mRNA increased significantly with growth (p<0.01). The expression level of OLR1 mRNA in obese-type pigs was significantly higher than that of lean-type pigs of the same monthly age (p<0.05). In adipose tissue, the expression of OLR1 correlated with $PPAR{\gamma}2$, FAS and SREBP-1c, but not TGH or C/EBP${\alpha}$. In conclusion, OLR1 was highly associated with fat deposition and its transcription, as suggested by high correlations, was possibly regulated by $PPAR{\gamma}2$ and SREBP-1c.

• Asian-Australasian Journal of Animal Sciences
• /
• 제26권8호
• /
• pp.1189-1196
• /
• 2013

Adipose tissue development and function play a critical role in the regulation of energy balance, lipid metabolism, and the pathophysiology of metabolic syndromes. Although the effect of zinc ascorbate supplementation in diabetes or glycemic control is known in humans, the underlying mechanism is not well described. Here, we investigated the effect of a zinc-chelated vitamin C (ZnC) compound on the adipogenic differentiation of 3T3-L1 preadipocytes. Treatment with ZnC for 8 d significantly promoted adipogenesis, which was characterized by increased glycerol-3-phosphate dehydrogenase activity and intracellular lipid accumulation in 3T3-L1 cells. Meanwhile, ZnC induced a pronounced up-regulation of the expression of glucose transporter type 4 (GLUT4) and the adipocyte-specific gene adipocyte protein 2 (aP2). Analysis of mRNA and protein levels further showed that ZnC increased the sequential expression of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein alpha (C/$EBP{\alpha}$), the key transcription factors of adipogenesis. These results indicate that ZnC could promote adipogenesis through $PPAR{\gamma}$ and C/$EBP{\alpha}$, which act synergistically for the expression of aP2 and GLUT4, leading to the generation of insulin-responsive adipocytes and can thereby be useful as a novel therapeutic agent for the management of diabetes and related metabolic disorders.