• Title/Summary/Keyword: genetic regulation

Search Result 501, Processing Time 0.02 seconds

Cyclic AMP response element binding (CREB) protein acts as a positive regulator of SOX3 gene expression in NT2/D1 cells

  • Kovacevic-Grujicic, Natasa;Mojsin, Marija;Popovic, Jelena;Petrovic, Isidora;Topalovic, Vladanka;Stevanovic, Milena
    • BMB Reports
    • /
    • v.47 no.4
    • /
    • pp.197-202
    • /
    • 2014
  • SOX3 is one of the earliest neural markers in vertebrates, playing the role in specifying neuronal fate. In this study we have established first functional link between CREB and human SOX3 gene which both have important roles in the nervous system throughout development and in the adulthood. Here we demonstrate both in vitro and in vivo that CREB binds to CRE half-site located -195 to -191 within the human SOX3 promoter. Overexpression studies with CREB or its dominant-negative inhibitor A-CREB indicate that this transcription factor acts as a positive regulator of basal SOX3 gene expression in NT2/D1 cells. This is further confirmed by mutational analysis where mutation of CREB binding site results in reduction of SOX3 promoter activity. Our results point at CREB as a positive regulator of SOX3 gene transcription in NT2/D1 cells, while its contribution to RA induction of SOX3 promoter is not prominent.

TCP10L negatively regulates alpha-fetoprotein expression in hepatocellular carcinoma

  • Shen, Suqin;Feng, Huan;Liu, Longjiang;Su, Wei;Yu, Long;Wu, Jiaxue
    • BMB Reports
    • /
    • v.53 no.8
    • /
    • pp.431-436
    • /
    • 2020
  • Alpha-fetoprotein (AFP) is one of the most commonly used and reliable biomarkers for Hepatocellular carcinoma(HCC). However, the underlying mechanism of AFP expression in HCC is poorly understood. In this study, we found that TCP10L, a gene specifically expressed in the liver, is down-regulated in HCC and that its expression inversely correlates with AFP expression. Moreover, overexpression of TCP10L suppresses AFP expression whereas knockdown of TCP10L increases AFP expression, suggesting that TCP10L might be a negative regulator of AFP. We found that TCP10L is associated with the AFP promoter and inhibits AFP promoter-driven transcriptional activity. Taken together, these results indicate that TCP10L negatively regulates AFP expression in HCC and that it could be a potential prognostic marker and therapeutic target for HCC.

Longevity Genes: Insights from Calorie Restriction and Genetic Longevity Models

  • Shimokawa, Isao;Chiba, Takuya;Yamaza, Haruyoshi;Komatsu, Toshimitsu
    • Molecules and Cells
    • /
    • v.26 no.5
    • /
    • pp.427-435
    • /
    • 2008
  • In this review, we discuss the genes and the related signal pathways that regulate aging and longevity by reviewing recent findings of genetic longevity models in rodents in reference to findings with lower organisms. We also paid special attention to the genes and signals mediating the effects of calorie restriction (CR), a powerful intervention that slows the aging process and extends the lifespan in a range of organisms. An evolutionary view emphasizes the roles of nutrient-sensing and neuroendocrine adaptation to food shortage as the mechanisms underlying the effects of CR. Genetic and non-genetic interventions without CR suggest a role for single or combined hormonal signals that partly mediate the effect of CR. Longevity genes fall into two categories, genes relevant to nutrient-sensing systems and those associated with mitochondrial function or redox regulation. In mammals, disrupted or reduced growth hormone (GH)-insulin-like growth factor (IGF)-1 signaling robustly favors longevity. CR also suppresses the GH-IGF-1 axis, indicating the importance of this signal pathway. Surprisingly, there are very few longevity models to evaluate the enhanced anti-oxidative mechanism, while there is substantial evidence supporting the oxidative stress and damage theory of aging. Either increased or reduced mitochondrial function may extend the lifespan. The role of redox regulation and mitochondrial function in CR remains to be elucidated.

Regulation of Sulfur Metabolism in Cephalosporium acremonium (Cephalosporium acremonium에서 황화합물 대사의 조절)

  • Lee, Kyoung;Park, Sang-Ho;Lee, Jung-Joon;Mheen, Tae-Ick
    • Microbiology and Biotechnology Letters
    • /
    • v.15 no.5
    • /
    • pp.361-367
    • /
    • 1987
  • A DL-seleno-methionine resistant mutant, Cephalosporium acremonium MS-92 showed increased activities of sulfate and L-methionine uptake than the parent strain, and accumulated excess methionine and S-adenosylmethionine (SAM) intracellularly. And the sulfate uptake system was severely inhibited by L-cysteine. In crude enzyme extracts, the mutant MS-92 showed lower L-serine sulfhydrylase (identical with cystathionine $\beta$-synthase) activity than the parent. Also, cysteine desulfhydrylase activity, an index of intracellular L-cysteine concentration, of the mutant MS-92 was decreased by about 50% as com-pared with that of the parent. Thus, it was supposed that the mutant MS-92 should have n lower level of L-cysteine than the parent. In C. acremonium like A. nidulans, the enzymes related to the biosynthesis of methionine might be regulated by L-cysteine, but not by methionine or SAM.

  • PDF

Genetic and Expression Analysis of the SIRT1 Gene in Gastric Cancers

  • Zhang, Cao;Song, Jae-Hwi;Kang, Young-Whi;Yoon, Jung-Hwan;Nam, Suk-Woo;Lee, Jung-Young;Park, Won-Sang
    • Journal of Gastric Cancer
    • /
    • v.10 no.3
    • /
    • pp.91-98
    • /
    • 2010
  • Purpose: Silent mating-type information regulation 2 homologue 1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent deacetylase. SIRT1 plays an important role in the regulation of cell death/survival and stress response in mammals. The aim of this study was to investigate whether the SIRT1 gene is involved in the development or progression of gastric cancers. Materials and Methods: SIRT1 and p53 genes in 86 gastric cancers were examined for genetic alterations by PCR-single strand conformation polymorphism sequencing, as well as SIRT1 protein expression in 170 gastric cancers by immunohistochemistry. Results: In the genetic analysis, we found SIRT1 and p53 mutations in two and 12 cases, respectively. Two missense mutations, c.599 C>T (T200I) and c.1258 G>A (E420K), were detected in the SIRT1 gene coding region. The SIRT1 and p53 mutation were found in mutually exclusive gastric cancers. The immunohistochemistry revealed that SIRT1 overexpression was found in 95 (55.9%) of 170 gastric cancers. Altered SIRT1 expression was not statistically associated with clinicopathological parameters, including tumor differentiation, location, lymph node metastasis, or p53 expression. Two cases with an SIRT1 mutation showed increased SIRT1 expression. Conclusions: These results suggest that genetic alterations and overexpression of the SIRT1 gene may contribute to gastric cancer development.

Associations of Ubiquitin-Specific Protease Genes with Resilience and Social Anxiety in Healthy Youths

  • Seo, Jun Ho;Park, Chun Il;Kim, Se Joo;Kang, Jee In
    • Anxiety and mood
    • /
    • v.15 no.2
    • /
    • pp.122-126
    • /
    • 2019
  • Objective : Dynamic proteolysis, through the ubiquitin-proteasome system, is an important molecular mechanism for the constant regulation of synaptic plasticity and stress responses in humans. In this study, we examined whether genetic variants in the ubiquitin-specific peptidase (USP) genes were associated with psychological traits of resilience and susceptibility to neuropsychiatric disorders for each gender. Methods : A total of 344 Korean healthy youths (190 males, 154 females) were included in the study. A genotyping of rs2241646 of USP2 and rs346006 of USP46 was performed. The Connor-Davidson Resilience Scale and Brief Fear of Negative Evaluation Scale were administered for measuring trait resilience and social anxiety, respectively. The genetic associations of the USP variants were tested using multiple analyses of covariance with psychological traits as dependent variables after controlling for age in each gender. Results : For USP2 rs2241646, women with the TT genotype showed significantly higher resilience and lower social anxiety, as compared to those carrying the C allele. There were no associations between USP46 rs346005 and the psychological traits in both genders. Conclusions : The present study showed a possible genetic association between the USP2 rs2241646 and stress resilience and trait anxiety in women. The findings suggest that ubiquitin-proteasome system may be related to the resilience and susceptibility to stress-related neuropsychiatric disorders such as anxiety disorders, possibly through the regulation of dynamic proteolysis responses to stress.

Flower color modification by genetic engineering

  • Masako, Fukuchi-Mizutani;Tanaka, Yoshikazu
    • Proceedings of the Korean Society of Plant Biotechnology Conference
    • /
    • 2005.11a
    • /
    • pp.3-8
    • /
    • 2005
  • Torenia hybridacv. Summerwave Blue and Violet mainly produce delphinidin. Down regulation of their flavonoid 3'-hydroxylase and flavonoid 3',5'-hydroxylase (F3'5'H) genes and over expression of rose or pelargonium dihydroflavonol 4-reductase (DFR) cDNA yielded pelargonidin-based bright pink flowers. Nierembergia cv. Fairybells lack pink color as they produced only delphinidin and flavonols. Pelargonidin-based pink flowers were achieved by down regulation of F3'5'H and flavonol synthase genes and over expressing rose DFR cDNA. Introduction of petunia F3'5'H and DFR cDNAs into white carnations deficient in DFR activity produced violet carnations, which arc now commercialized in the USA, Canada, Australia, Europe and Japan. Introduction of pansy F3'5'H and iris DFR cDNAs and down regulation of rose DFR gene produced rose flowers which accumulates delphinidin imparting novel violet color.

  • PDF

Biosynthetic Regulation of Invertase from Thermophilic and Alkalophilic Bacillus sp. TA-11 (고온성이며 호알칼리성인 Bacillus sp. TA-11이 생성하는 Invertase의 생합성 조절)

  • Kim, Jae-Ho;Kim, Na-Mi;Kim, Dong-Woo
    • The Korean Journal of Food And Nutrition
    • /
    • v.15 no.2
    • /
    • pp.126-130
    • /
    • 2002
  • Regulation of invertase biosynthesis was studied in thermophilic and alkalophilic Bacillus sp. TA-11. Biosynthesis of the invertase was effectively induced in the presence of 10 mM sucrose for 180 min. Glucose repressed the invertase induction by sucrose and as late as addition time of glucose, the invertase formation was increased, indicating that glucose repression was occurred by inducer exclusion. Catabolite repression was reduced a little by the addition of cAMP for 180 min of induction.

Biosynthetic Regulation of Inulinase from Bacillus sphaericus 188-1 (Bacillus sphaericus 188-1이 생성하는 Inulinase의 생합성 조절)

  • Kim, Na-Mi;Lee, Jong-Soo
    • The Korean Journal of Food And Nutrition
    • /
    • v.14 no.1
    • /
    • pp.77-81
    • /
    • 2001
  • Regulation of inulinase biosynthesis was studied in Bacillus sphaericus 188-1 Biosynthesis of inulinase was effectively induced in the presence of 0.5% inulin for 8 hrs. Fructose (0.5%) repressed the inulinase induction by inulin and as late as addition time of fructose, inulinase formation was decreased. Catabolite repression was not reduced by the addition of CAMP for 8 hrs of induction.

  • PDF

Regulation of Melanogenesis as Studied by Chemical Analysis of Melanins

  • Ito, Shosuke
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.26 no.2
    • /
    • pp.41-50
    • /
    • 2000
  • - Biochemical studies show that in the process of mixed melanogenesis, cysteinyldopas are produced first which are next oxidized to give pheomelanin. After all of the cysteine is consumed, eumelanin is then deposited on the preformed pheomelanin. - In vitro and in vivo studies show that tyrosinase activity is the most important factor that regulates the switch of melanogenesis, with higher activities increasing melanogenesis, especially eumelanogenesis. - In culturted melanocytes, the tyrosine to cysteine ratio is critical in determining the eumelanin to pheomelanin ratio. - Our HPLC method to analyze eumelanin and pheomelanin has become a useful tool in the study of melanogenesis regulation. There are many problems to be solved before we fully understand the regulation of melanogenesis. Mutations in mouse models are ideal models for studying the genetic and molecular control of melanogenesis. Even in the mouse models, it is not known how cysteine is excluded from being incorporated into melanins in black and other eumelaninc mice, Conversely, it is not known how cysteine is continuously incorporated into pheomelanin in lethal yellow and recessive yellow mice.

  • PDF