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Chang YN, Shang TT, Tang QQ, Long XR, Zhao RQ, Xu HM. [History of epidemiological changes of human monkeypox]. Zhonghua Er Ke Za Zhi 2022; 60:836-839. [PMID: 35922201 DOI: 10.3760/cma.j.cn112140-20220607-00520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- Y N Chang
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
| | - T T Shang
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
| | - Q Q Tang
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
| | - X R Long
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
| | - R Q Zhao
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
| | - H M Xu
- Department of Infectious Disease, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Developmental Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 401122, China
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Lyu XY, Wang GP, Tang QQ, Cheng ZZ, Gui W, Tian YH. [Clinical characteristics of "classical" and "non-classical" paraneoplastic neurological syndrome]. Zhonghua Yi Xue Za Zhi 2021; 101:615-619. [PMID: 33685041 DOI: 10.3760/cma.j.cn112137-20200616-01870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the clinical features of classical and non-classical paraneoplastic neurological syndrome (PNS). Methods: From 2015 to 2020, 48 cases of definite PNS admitted to the First Affiliated Hospital of University of Science and Technology of China were retrospectively collected, and classification, clinical characteristics, onconeural antibodies and primary tumors were analyzed. The included cases were divided into classical and non-classical groups according to Graus criteria, and the differences of clinical characteristics, onconeural antibodies, combined tumors, time of diagnosis and mortality were compared between the two groups. Results: Among the 48 confirmed patients, 21 (43.8%) were positive for well-characterized onconeural antibodies. There were 28 cases (58.3%) and 20 cases (41.7%) in classic and non-classical PNS groups, respectively. No significant differences of age, sex, clinical involvement site, characteristic positive antibody type, tumor diagnosis rate and follow-up mortality were found between the two groups (all P>0.05). The time of diagnosis in the non-classical PNS group was 3.0 (2.0, 6.5) months, which was significantly longer than that in the classical PNS group 1.0(0.6, 3.0) months (P<0.05). Meanwhile, the combination rate of non-characteristic antibodies in the classical PNS group (10 cases, 35.7%) was significantly higher than that in the non-classical PNS group (1 case, 5.0%) (P=0.016). During the follow-up, 39 patients (81.3%) with tumor were confirmed, and 29 patients (60.4%) were diagnosed with PNS before the tumor was found. Conclusions: The"non-classical"PNSs are common in clinical settings. Diagnosis may be delayed due to the nonclassical symptoms of the patients. When patients have clinical symptoms related to PNS, onconeural antibodies should be detected and the relevant tumors should also be screened. Patients have positive antibodies but with no tumors should be closely followed up for more than 5 years.
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Affiliation(s)
- X Y Lyu
- Department of Neurology, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001, China
| | - G P Wang
- Department of Neurology, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001, China
| | - Q Q Tang
- Department of Neurology, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001, China
| | - Z Z Cheng
- Department of Neurology, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001, China
| | - W Gui
- Department of Neurology, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001, China
| | - Y H Tian
- Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
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3
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Nairismägi ML, Gerritsen ME, Li ZM, Wijaya GC, Chia BKH, Laurensia Y, Lim JQ, Yeoh KW, Yao XS, Pang WL, Bisconte A, Hill RJ, Bradshaw JM, Huang D, Song TLL, Ng CCY, Rajasegaran V, Tang T, Tang QQ, Xia XJ, Kang TB, Teh BT, Lim ST, Ong CK, Tan J. Oncogenic activation of JAK3-STAT signaling confers clinical sensitivity to PRN371, a novel selective and potent JAK3 inhibitor, in natural killer/T-cell lymphoma. Leukemia 2018; 32:1147-1156. [PMID: 29434279 PMCID: PMC5940653 DOI: 10.1038/s41375-017-0004-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 11/17/2017] [Accepted: 12/04/2017] [Indexed: 02/06/2023]
Abstract
Aberrant activation of the JAK3-STAT signaling pathway is a characteristic feature of many hematological malignancies. In particular, hyperactivity of this cascade has been observed in natural killer/T-cell lymphoma (NKTL) cases. Although the first-in-class JAK3 inhibitor tofacitinib blocks JAK3 activity in NKTL both in vitro and in vivo, its clinical utilization in cancer therapy has been limited by the pan-JAK inhibition activity. To improve the therapeutic efficacy of JAK3 inhibition in NKTL, we have developed a highly selective and durable JAK3 inhibitor PRN371 that potently inhibits JAK3 activity over the other JAK family members JAK1, JAK2, and TYK2. PRN371 effectively suppresses NKTL cell proliferation and induces apoptosis through abrogation of the JAK3-STAT signaling. Moreover, the activity of PRN371 has a more durable inhibition on JAK3 compared to tofacitinib in vitro, leading to significant tumor growth inhibition in a NKTL xenograft model harboring JAK3 activating mutation. These findings provide a novel therapeutic approach for the treatment of NKTL.
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Affiliation(s)
- M -L Nairismägi
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | | | - Z M Li
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - G C Wijaya
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - B K H Chia
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - Y Laurensia
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - J Q Lim
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - K W Yeoh
- Department of Radiation Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - X S Yao
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - W L Pang
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - A Bisconte
- Principia Biopharma, South San Francisco, CA, USA
| | - R J Hill
- Principia Biopharma, South San Francisco, CA, USA
| | - J M Bradshaw
- Principia Biopharma, South San Francisco, CA, USA
| | - D Huang
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - T L L Song
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - C C Y Ng
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - V Rajasegaran
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - T Tang
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | - Q Q Tang
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - X J Xia
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - T B Kang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China
| | - B T Teh
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore.,Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - S T Lim
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore.,Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore.,Office of Education, Duke-NUS Graduate Medical School, Singapore, Singapore
| | - C K Ong
- Lymphoma Genomic Translational Research Laboratory, Division of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore. .,Genome Institute of Singapore, A*STAR, Singapore, Singapore.
| | - J Tan
- Laboratory of Cancer Epigenome, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, Singapore. .,State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, China.
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Tang QQ, Feng L, Jiang WD, Liu Y, Jiang J, Li SH, Kuang SY, Tang L, Zhou XQ. Effects of dietary copper on growth, digestive, and brush border enzyme activities and antioxidant defense of hepatopancreas and intestine for young grass carp (Ctenopharyngodon idella). Biol Trace Elem Res 2013; 155:370-80. [PMID: 24052363 DOI: 10.1007/s12011-013-9785-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 08/06/2013] [Indexed: 11/28/2022]
Abstract
To investigate the effects of dietary copper (Cu) on fish growth, digestive and absorptive enzyme activities, and antioxidant status in the hepatopancreas and intestine, young grass carp (Ctenopharyngodon idella) (282±2.8 g) were fed six diets containing 0.74 (basal diet), 2.26, 3.75, 5.25, 6.70, and 8.33 mg Cu /kg diet for 8 weeks. Results showed that percentage weight gain (PWG) and feed intake were increased with dietary Cu levels up to 3.75 mg/kg diet. In addition, the positive effects of dietary Cu at a level 3.75 or 5.25 mg/kg diet on trypsin, chymotrypsin, and lipase activities in the hepatopancreas and of Na(+), K(+)-ATPase, alkaline phosphatase, creatine kinase, and γ-glutamyl transpeptidase activities in three intestine segments produced significantly (P<0.05) better feed efficiency (FE). However, amylase activity in the hepatopancreas was decreased by dietary Cu levels up to 3.75 mg/kg diet (P<0.05). In addition, dietary Cu at 3.75 or 5.25 mg/kg diet decreased malondialdehyde and protein carbonyl content partly by significantly (P<0.05) increasing the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and glutathione content in the hepatopancreas and intestine. Collectively, dietary Cu improved growth and digestive and absorptive capacity and decreased lipid peroxidation and protein oxidation partly by enhancing antioxidant defense in the hepatopancreas and intestine. The dietary Cu requirement for PWG, plasma ceruloplasmin activity, and FE of young grass carp (282-688 g) were 4.78, 4.95, and 4.70 mg/kg diet, respectively.
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Affiliation(s)
- Q Q Tang
- Animal Nutrition Institute, Sichuan Agricultural University, Sichuan,, Cheng Du, 625014, China
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Feng T, Chu MX, Cao GL, Tang QQ, Di R, Fang L, Li N. Polymorphisms of caprine POU1F1 gene and their association with litter size in Jining Grey goats. Mol Biol Rep 2011; 39:4029-38. [PMID: 21769479 DOI: 10.1007/s11033-011-1184-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2010] [Accepted: 07/06/2011] [Indexed: 10/18/2022]
Abstract
Seven pairs of primers were designed to amplify 5' promoter region, six exons and partial introns and to detect the polymorphisms of POU1F1 gene in five goat breeds with different prolificacy. The results showed that six mutations were identified in caprine POU1F1 gene including C256T in exon 3, C53T and T123G in intron 3, and G682T (A228S), T723G and C837T in exon 6. The former four mutations were novel SNPs in goat POU1F1 gene. The 53 and 123 loci were in complete linkage disequilibrium in five caprine breeds. Regarding the 256 locus, the Jining Grey goat does with genotype CT had 0.66 kids more than those with genotype CC (P < 0.05), while does with genotype GT had 0.63 (P < 0.05) kids more than those with genotype GG at the 682 locus. The present study preliminarily showed an association between allele T at the 256 and 682 loci of POU1F1 gene and high litter size in Jining Grey goats. Totally 16 haplotypes and 50 genotypes were identified at the above six loci in POU1F1 gene of five goat breeds. Three common haplotypes (hap2, hap3 and hap4) were identified in five goat breeds joined. Four specific haplotypes (hap7, hap9, hap11 and hap13) were detected in Jining Grey goats. The predominant haplotype was hap1 (35.29% and 48.25%) in both Jining Grey and Guizhou White goats, while hap4 (50%) in Boer goats, and hap2 (42.86% and 38.75%) in both Wendeng Dairy and Liaoning Cashmere goats. The most frequent genotypes at six loci in the above five goat breeds were hap1/hap2 (14.38%) and hap1/hap4 (14.38%), hap1/hap2 (38.60%), hap4/hap4 (40.91%), hap2/hap4 (26.53%), hap2/hap5 (20.00%), respectively. The Jining Grey goat does with nine genotypes analyzed of POU1F1 gene showed no obvious difference in litter size.
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Affiliation(s)
- T Feng
- Key Laboratory of Farm Animal Genetic Resources and Utilization of Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, People's Republic of China
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Chu MX, Yang J, Feng T, Cao GL, Fang L, Di R, Huang DW, Tang QQ, Ma YH, Li K, Li N. GDF9 as a candidate gene for prolificacy of Small Tail Han sheep. Mol Biol Rep 2010; 38:5199-204. [PMID: 21184179 DOI: 10.1007/s11033-010-0670-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 12/12/2010] [Indexed: 11/29/2022]
Abstract
Growth differentiation factor 9 (GDF9) which controls the fecundity of Belclare, Cambridge, Santa Ines, Moghani, Ghezel and Thoka ewes was studied as a candidate gene for the prolificacy of Small Tail Han sheep. According to the sequence of ovine GDF9 gene, six pairs of primers were designed to detect single nucleotide polymorphisms of two exons of GDF9 gene in both high fecundity breed (Small Tail Han sheep) and low fecundity breed (Dorset sheep) by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Only the products amplified by primers 2-1 and 2-2 displayed polymorphisms. For primer 2-1, three genotypes (AA, AB and BB) were detected in both sheep breeds. Sequencing revealed one silent mutation (G477A) in exon 2 of GDF9 gene in the BB genotype in comparison with the AA, which was known as G3 mutation of GDF9 gene in Belclare and Cambridge ewes. The relationship of least squares means for litter size was AA > AB > BB in Small Tail Han sheep (P > 0.05). For primer 2-2, two genotypes (CC and CD) were detected in both sheep breeds. Sequencing revealed one novel single nucleotide mutation (G729T) in exon 2 of GDF9 gene in the CD genotype in comparison with the CC, which resulted in an amino acid change (Gln243His). The ewes with mutation heterozygous genotype CD had 0.77 (P < 0.01) lambs more than those with wild type CC in Small Tail Han sheep. These results preliminarily indicated that allele D of GDF9 gene was a potential genetic marker for improving litter size in Small Tail Han sheep.
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Affiliation(s)
- M X Chu
- Key Laboratory of Farm Animal Genetic Resources and Utilization of Ministry of Agriculture, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, People's Republic of China.
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Lu PY, Tang QQ, Xie FY, Xu J, Liu Y, Scaria PV, Aslam A, Woodle MC. Preclinical Study of mAb-siRNA Combination Anti-Angiogenesis Therapy for Treatment of Colorectal Cancer. J Immunother 2005. [DOI: 10.1097/01.cji.0000190937.26396.9f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tang QQ, Lane MD. Role of C/EBP homologous protein (CHOP-10) in the programmed activation of CCAAT/enhancer-binding protein-beta during adipogenesis. Proc Natl Acad Sci U S A 2000; 97:12446-50. [PMID: 11050169 PMCID: PMC18783 DOI: 10.1073/pnas.220425597] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Hormone induction of growth-arrested preadipocytes triggers mitotic clonal expansion followed by expression of CCAAT/enhancer-binding protein (C/EBP)alpha and differentiation into adipocytes. The order of these events is critical because C/EBPalpha is antimitotic and its expression prematurely would block the mitotic clonal expansion required for differentiation. C/EBPbeta, a transcriptional activator of the C/EBPalpha gene, is expressed early in the differentiation program, but lacks DNA-binding activity and fails to localize to centromeres until preadipocytes traverse the G(1)-S checkpoint of mitotic clonal expansion. Evidence is presented that dominant-negative CHOP-10 expressed by growth-arrested preadipocytes transiently sequesters C/EBPbeta by heterodimerization. As preadipocytes reach S phase, CHOP-10 is down-regulated, apparently releasing C/EBPbeta from inhibitory constraint and allowing transactivation of the C/EBPalpha gene. In support of these findings, up-regulation of CHOP-10 with the protease inhibitor N-acetyl-Leu-Leu-norleucinal prevents activation of C/EBPbeta, expression of C/EBPalpha, and adipogenesis.
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Affiliation(s)
- Q Q Tang
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, MD 21209, USA.
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9
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Abstract
Members of the C/EBP family of transcription factors play essential roles in the adipocyte differentiation program. Treatment of growth-arrested 3T3-L1 preadipocytes with appropriate hormonal agents causes the cells to synchronously reenter the cell cycle and to undergo mitotic clonal expansion. Expression of C/EBPbeta and delta occur early in clonal expansion, later followed by C/EBPalpha (which is anti-mitotic) as the cells exit the cell cycle begin to express adipocyte genes. C/EBPalpha serves as transcriptional activator of many adipocyte genes whose expression produce the adipocyte phenotype. Recent work in this laboratory has focussed on the roles of C/EBPbeta and delta in the differentiation program, in particular the mechanisms by which they activate transcription of the C/EBPalpha gene. Several regulatory elements, both repressive and activating, in proximal promoter of the gene have been identified. The cognate transacting factors that interact with these elements have been characterized and their functions elucidated. These factors have been incorporated into a model for a cascade that leads to transcriptional activation of the C/EBPalpha gene and the terminal steps in the differentiation program.
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Affiliation(s)
- M D Lane
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21205, USA
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10
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Tang QQ, Lane MD. Activation and centromeric localization of CCAAT/enhancer-binding proteins during the mitotic clonal expansion of adipocyte differentiation. Genes Dev 1999; 13:2231-41. [PMID: 10485846 PMCID: PMC316997 DOI: 10.1101/gad.13.17.2231] [Citation(s) in RCA: 300] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Hormonal induction of 3T3-L1 preadipocytes triggers a cascade of events that initiate differentiation into adipocytes. CCAAT/enhancer-binding proteins beta and delta (C/EBPbeta/delta) are expressed early in the differentiation program, but are not immediately active. After a long lag, C/EBPbeta/delta become competent to bind to the C/EBP regulatory element in the C/EBPalpha gene promoter, C/EBPalpha being a transcriptional activator of numerous adipocyte genes. As C/EBPbeta/delta acquire binding activity, they become localized to centromeres as preadipocytes synchronously enter S phase at the onset of mitotic clonal expansion. Localization to centromeres occurs through C/EBP consensus-binding sites in centromeric satellite DNA. C/EBPalpha, which is antimitotic, becomes centromere-associated much later in the differentiation program as mitotic clonal expansion ceases and the cells become terminally differentiated.
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Affiliation(s)
- Q Q Tang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 USA
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11
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Abstract
Expression of C/EBPalpha is required for differentiation of 3T3-L1 preadipocytes into adipocytes. Previous investigations indicated that transcription of the C/EBPalpha gene is sequentially activated during differentiation, initially by C/EBPbeta and C/EBPdelta and later by C/EBPalpha (autoactivation). These events are mediated by a C/EBP regulatory element in the promoter of the C/EBPalpha gene. This article presents evidence that members of the Sp family, notably Sp1, act repressively on the C/EBPalpha promoter prior to the induction of differentiation. Sp1 was shown to bind to a GC box at the 5' end of the C/EBP regulatory element in the C/EBPalpha promoter and, in so doing, to competitively prevent binding to and transactivation of the promoter by the C/EBPs. One of the differentiation inducers methylisobutylxanthine (a cAMP phosphodiesterase inhibitor) or Forskolin, both of which increase the cellular cAMP level, causes down-regulation of Sp1. This decrease in Sp1 level early in the differentiation program appears to facilitate access of C/EBPbeta and/or C/EBPdelta to the C/EBP regulatory element and, thereby, derepression of the C/EBPalpha gene.
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Affiliation(s)
- Q Q Tang
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Jiang MS, Tang QQ, McLenithan J, Geiman D, Shillinglaw W, Henzel WJ, Lane MD. Derepression of the C/EBPalpha gene during adipogenesis: identification of AP-2alpha as a repressor. Proc Natl Acad Sci U S A 1998; 95:3467-71. [PMID: 9520389 PMCID: PMC19859 DOI: 10.1073/pnas.95.7.3467] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/31/1997] [Indexed: 02/06/2023] Open
Abstract
During adipogenesis, CCAAT/enhancer binding protein alpha (C/EBPalpha) serves as a pleiotropic transcriptional activator of adipocyte genes. Previously, we identified dual repressive elements in the C/EBPalpha gene and a putative transacting factor (C/EBPalpha undifferentiated protein, or CUP) expressed by preadipocytes, but not adipocytes, that bind to these elements. In the present investigation, CUP was purified 17,000-fold from nuclear extracts of 3T3-L1 preadipocytes. Amino acid sequence and mass spectral analysis of tryptic peptides derived from purifed CUP (molecular mass approximately 50 kDa) revealed that the repressor is (or contains) an isoform of the transcription factor, AP-2alpha. Electrophoretic mobility shift and Western blot analysis on purified CUP and preadipocyte nuclear extracts confirmed the identity of CUP as AP-2alpha. Both AP-2alpha protein and CUP binding activity are expressed by preadipocytes and then decrease concomitantly during differentiation of 3T3-L1 preadipocytes into adipocytes. Consistent with a repressive role of AP-2alpha/CUP, an AP-2alpha1 expression vector, cotransfected with a C/EBPalpha promoter-reporter construct into 3T3-L1 adipocytes, inhibited reporter gene transcription. Taken together with previous results, these findings suggest that in preadipocytes the C/EBPalpha gene is repressed by AP-2alpha/CUP, which, upon induction of differentiation, is down-regulated, allowing expression of the gene.
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Affiliation(s)
- M S Jiang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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13
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Abstract
During adipocyte differentiation, the expression of C/EBPalpha is activated, which in turn serves to transcriptionally activate numerous adipocyte genes. A previous search for cis elements that regulate transcription of the C/EBPalpha gene led to the identification of a potential repressive element within the proximal 5' flanking region of the gene. Nuclear extracts from 3T3-L1 preadipocytes, but not adipocytes, were found to contain a factor, CUP (C/EBPalpha undifferentiated protein), that binds to this site (the CUP-1 site). In the present investigation, we show that C/EBPalpha promoter-luciferase constructs containing both the proximal 5' flanking and the entire 5' untranslated regions of the gene exhibit an expression pattern during adipocyte differentiation comparable to that of the endogenous C/EBPalpha gene. Mutation of the CUP-1 site in these constructs had little effect on reporter gene expression; however, when this mutation was combined with deletion of the 5' untranslated region, reporter gene expression by preadipocytes was dramatically up-regulated. Consistent with this finding, a second CUP binding site (the CUP-2 site) was identified in the 5' untranslated region. Although mutation of either CUP element in constructs containing both the 5' flanking and 5' untranslated region had little effect on reporter gene transcription, mutation of both CUP elements markedly activated transcription. Thus, it appears that dual CUP regulatory elements repress transcription of the C/EBPalpha gene prior to induction of the adipocyte differentiation program.
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Affiliation(s)
- Q Q Tang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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14
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Song CZ, Tierney CJ, Loewenstein PM, Pusztai R, Symington JS, Tang QQ, Toth K, Nishikawa A, Bayley ST, Green M. Transcriptional repression by human adenovirus E1A N terminus/conserved domain 1 polypeptides in vivo and in vitro in the absence of protein synthesis. J Biol Chem 1995; 270:23263-7. [PMID: 7559479 DOI: 10.1074/jbc.270.40.23263] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The human adenovirus E1A 243R protein (243 residues) transcriptionally represses a set of cellular genes that regulate cellular growth and differentiation. We describe two lines of evidence that E1A repression does not require cellular protein synthesis but instead involves direct interaction with a cellular protein(s). First, E1A 243R protein represses an E1A-repressible promoter in the presence of inhibitors of protein synthesis, as shown by cell microinjection-in situ hybridization. Second, E1A 243R protein strongly represses transcription in vitro from promoters of the E1A-repressible genes, human collagenase, and rat insulin type II. Repression in vitro is promoter-specific, and an E1A polypeptide containing only the N-terminal 80 residues is sufficient for strong repression both in vivo and in vitro. By use of a series of E1A 1-80 deletion proteins, the E1A repression function was found to require two E1A sequence elements, one within the nonconserved E1A N terminus, and the second within a portion of conserved region 1 (40-80). These domains have been reported to possess binding sites for several cellular transcription regulators, including p300, Dr1, YY1, and the TBP subunit of TFIID. The in vitro transcription-repression system described here provides a powerful tool for the further analysis of molecular mechanism and the possible role of these cellular factors.
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Affiliation(s)
- C Z Song
- Institute for Molecular Virology, Saint Louis University School of Medicine, Missouri, USA
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