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2.
Biol Reprod ; 64(1): 30-5, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11133655

RESUMO

The effect of the oviductal environment on gene expression in 2-cell mouse embryos was examined with mRNA differential display. Embryos used for experiments were cultured in modified Whitten medium with or without oviductal tissue until late 2-cell stage. The results of sequencing indicated that the genes for ATP synthase (ATPase 6), S:-adenosylmethionine decarboxylase (S:-AMDC) and nuclear autoantigenic sperm protein (NASP) were differentially expressed in embryos cultured in the oviductal environment (nonblocking culture condition). The ATPase 6 gene is encoded by mitochondrial DNA and is essential for the production of ATP. This indicates that the expression of ATP synthesis-related genes at the 2-cell stage may be required to maintain normal development in vitro. S:-Adenosylmethionine decarboxylase decarboxylates adenosylmethionine, which is a substrate of DNA methylation. The expression of S:-AMDC may be responsible for the low level of methylation of preimplantation development. As NASP is a histone-binding protein that is thought to be testis and sperm specific, its function in embryos remains unclear. On the other hand, the Tcl1 gene and a novel gene, the c-1 gene, were strongly expressed in embryos cultured without oviductal tissue (blocking culture condition). The expression patterns of these genes are quite similar. However, the detailed functions of these genes in embryos remain to be determined.


Assuntos
Embrião de Mamíferos/metabolismo , Expressão Gênica , Adenosina Trifosfatases/genética , Trifosfato de Adenosina/biossíntese , Adenosilmetionina Descarboxilase/genética , Animais , Autoantígenos/genética , Blastocisto/metabolismo , Proteínas de Ciclo Celular , Técnicas de Cultura , Metilação de DNA , Eletroforese , Feminino , Fertilização in vitro , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Camundongos , Camundongos Endogâmicos ICR , Proteínas Nucleares/genética , Fatores de Iniciação de Peptídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Genome ; 43(6): 957-62, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11195349

RESUMO

Isolation and characterization were performed for cDNA encoding mouse testicular cell adhesion molecule-1 (TCAM-1) using 2908 bases coding for a protein having 548 amino acids (60 kDa). Mouse TCAM-1 protein was found to consist of seven domains for signal sequence, five immunoglobulin (Ig) domains, and the transmembrane plus cytoplasmic domain. TCAM-1 gene and the region linking it to growth hormone (GH) gene located downstream from the TCAM-1 gene were then analyzed. The mouse TCAM-1 gene was 11.6 kb in length with 8 exons; the same as for the 12.0 kb rat gene. The distance from the TCAM-1 to GH gene was 12.5 kb in the mouse genome, and 7.6 kb in the rat. By Northern hybridization, 3.1-kb TCAM-1 mRNA was detected in 17-day testis and would appear present in pachytene spermatocytes and round spermatids.


Assuntos
Expressão Gênica , Ligação Genética , Proteínas de Membrana/genética , Testículo/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Moléculas de Adesão Celular , Clonagem Molecular , DNA Complementar/análise , Hormônio do Crescimento/genética , Masculino , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , RNA Mensageiro/biossíntese , Homologia de Sequência de Aminoácidos
4.
Mamm Genome ; 8(5): 317-23, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9107674

RESUMO

To understand the role of chromatin structure in the expression of the mouse protamine 1, protamine 2, and transition protein 2 genes during spermatogenesis, we have examined the genomic organization of this cluster of "haploid-specific" genes. As seen in the human genome, protamine 2, transition protein 2, and approximately 2.8 kb of a CpG island, hereafter called CpG island-dTP2, were clustered in a small region. Methylation analyses of this region have demonstrated that i) unlike most other tissue-specific genes, the protamine 1, protamine 2, and transition protein 2 genes were located in a large methylated domain in round spermatids, the cell type where they are transcribed, ii) the protamine 1 gene was only partially methylated in somatic cells and in testes from 7-day-old mice, and iii) the approximately 2 kb upstream and downstream of the CpG island-dTP2 were only partially methylated in somatic tissues. DNase I analysis revealed the presence of at least five strong DNase I hypersensitive sites over the CpG island-dTP2 in somatic tissues, but not in germ cells, and sequence analysis indicated that the CpG island-dTP2 is homologous to a CpG island located approximately 10.6 kb downstream of the human transition protein 2 gene. Although the nature of a CpG island-dTP2 and the function of a CpG island-dTP2-containing somatic tissue-specific DNase I hypersensitive sites in close proximity to the germ cell-specific gene cluster are unclear, the "open" chromatin structure of the CpG island-dTP2 may be responsible for the partial methylation pattern of the flanking sequences including the transition protein 2 gene in somatic tissues.


Assuntos
Proteínas Cromossômicas não Histona/genética , Metilação de DNA , Família Multigênica , Protaminas/genética , Animais , Sequência de Bases , Clonagem Molecular , Ilhas de CpG , DNA/genética , Expressão Gênica , Haploidia , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Espermatogênese/genética
5.
J Biochem ; 119(2): 296-301, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8882721

RESUMO

To elucidate the mechanisms underlying cell type-specific expression of the growth hormone (GH) and prolactin (PRL) genes, we used rat pituitary-derived cell lines producing exclusively GH (GC cells) or PRL (235 cells), and examined the following: expression of transcription factors essential for GH and/or PRL gene expression; promoter/enhancer activity of the GH and PRL genes transiently introduced by transfection; and chromatin structures of the GH and PRL genes. Even in PRL-nonproducing GC cells, the PRL promoter/enhancer was more active than the GH promoter, and the transcription factors, Pit-1 and estrogen receptor (ER), essential for PRL gene expression were functional. The PRL promoter/enhancer of GC cells was normal. On DNase I sensitivity analysis of the chromatin structure, two hypersensitive sites were detected in PRL gene chromatin of PRL-producing 235 cells but none in that of GC cells. It thus follows that the major reason for absence of the expression of the endogenous PRL gene in GC cells is neither the lack of transcription factors necessary for PRL gene expression nor an anomaly of the PRL gene itself, but that the chromatin structure of the PRL gene differs in PRL-nonproducing and -producing cells. It was shown in this study that neither Pit-1 nor ER is required for conversion of the structure of PRL gene chromatin to a DNase I-hypersensitive state.


Assuntos
Cromatina/química , Expressão Gênica , Prolactina/genética , Animais , Linhagem Celular , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Hormônio do Crescimento/genética , Hipófise/citologia , RNA Mensageiro/genética , Ratos , Receptores de Estrogênio/genética , Receptores dos Hormônios Tireóideos/genética , Hormônios Tireóideos/farmacologia
6.
Nucleic Acids Res ; 23(12): 2236-44, 1995 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-7610053

RESUMO

In this study, a determination was made of the chromatin structure of the rat growth hormone (GH) gene locus by DNase I sensitivity analysis using GC [GH+, prolactin (PRL)-], 235 (GH-, PRL+), GH3 (GH+, PRL+) and liver (GH-, PRL-) cells. From 7 kb upstream from the transcription start site to 19 kb downstream from the polyadenylation site, two major DNase I-hypersensitive sites (M-DHS; UIA, UIIA) and three M-DHS (DIA, DII, DIII) were found within 2 kb upstream and 7 kb downstream regions, respectively. Two minor DHS (m-DHS; UIB, UIIB) in the upstream region and one m-DHS (DIB) downstream were shown to be associated with M-DHS. Thus, a total of five M-DHS and three m-DHS were mapped on the rat GH gene locus. Among these, five (UIIB, UIA, UIB, DIB, DIA) including two (UIA, DIA) M-DHS were specific for GH-producing cells. UIIA and DIII were M-DHS only in PRL-producing 235 cells while the major hypersensitivity of DII was detected in GH-producing cells and liver cells. Assessment of the enhancing activity of the DHS regions indicated novel enhancers in one upstream and two downstream regions that function well with the GH promoter in GC cells. These enhancers, each appearing different, coincided with m-DHS but not M-DHS in GC cells, and were not activated by Pit-1. Based on these observations, the following functions of five M-DHS and three m-DHS regions were defined: enhancer; locus control region (LCR); switch region serving for conversion from GH/PRL-producing cells to PRL-producing cells; and a region having a structural function in chromatin.


Assuntos
Cromatina/química , Cromatina/metabolismo , Desoxirribonuclease I/metabolismo , Elementos Facilitadores Genéticos , Hormônio do Crescimento/genética , Animais , Sítios de Ligação , Southern Blotting , Linhagem Celular , Proteínas de Ligação a DNA/farmacologia , Fígado/metabolismo , Prolactina/genética , Regiões Promotoras Genéticas , Ratos , Mapeamento por Restrição , Vírus 40 dos Símios/genética , Fator de Transcrição Pit-1 , Fatores de Transcrição/farmacologia
7.
Gene ; 153(2): 267-71, 1995 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-7875599

RESUMO

The promoter regions of the genes encoding the rat and chum salmon growth hormones (GH) and rat prolactin (PRL) were combined with a reporter gene and introduced into GH- and/or PRL-producing cells from rat. The rat GH and PRL promoters (pGH and pPRL, respectively) were most active in cells producing GH and PRL, respectively. The activity of the salmon pGH was much less than that of the rat pGH in rat GH-producing cells. The regulatory region required for cell-type-specific gene expression of pituitary hormones thus contains information, not only for cell-type specificity, but possibly for species specificity as well. A reporter plasmid containing the GH or somatolactin (SL) promoter and an effector plasmid having a gene encoding transcription factor Pit-1 (rat or salmon) were cotransfected into HeLa (human) or EPC (carp) cells. Rat and salmon Pit-1 were more active in HeLa and EPC cells, respectively, indicating that Pit-1 appears to interact species specifically with the transcription machinery.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Hormônio do Crescimento/genética , Prolactina/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/fisiologia , Ativação Transcricional/genética , Animais , Carpas , Linhagem Celular , Proteínas de Peixes , Genes Reporter/genética , Glicoproteínas/genética , Células HeLa , Humanos , Oncorhynchus keta , Hormônios Hipofisários/genética , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Especificidade da Espécie , Fator de Transcrição Pit-1 , Transfecção
9.
Biochim Biophys Acta ; 963(1): 35-41, 1988 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-3179328

RESUMO

Effects of MK-733 on the absorption and excretion of cholesterol in rabbits were examined using [3H]cholesterol. The animals were divided into six groups; three groups were fed a normal diet, and the other groups a cholesterol diet. MK-733 was administered orally as a single dose of 10 mg/kg on day 8, or multiple doses of 10 mg/kg once a day for 14 days. On the 8th day, [3H]cholesterol was given orally to each animal. In the groups fed a normal diet, single and consecutive administration of MK-733 did not affect the absorption and excretion of [3H]cholesterol. In the cholesterol-fed groups, however, single administration of MK-733 decreased the serum 3H radioactivity slightly, but did not affect the fecal excretion of [3H]cholesterol. However, the consecutive treatment with MK-733 clearly reduced the serum 3H radioactivity. The cumulative excretion of the fecal radioactivity of [3H]cholesterol in the MK-733 group (multiple) was higher than that in the control group. From these results, it is concluded that MK-733 inhibits the absorption of cholesterol from the gastrointestinal wall in cholesterol-fed rabbits.


Assuntos
Colesterol/farmacocinética , Inibidores de Hidroximetilglutaril-CoA Redutases , Lovastatina/análogos & derivados , Administração Oral , Animais , Colesterol na Dieta/administração & dosagem , Fezes/análise , Lovastatina/administração & dosagem , Lovastatina/farmacologia , Masculino , Coelhos , Sinvastatina , Sitosteroides/farmacologia
10.
Tohoku J Exp Med ; 132(2): 213-23, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7444945

RESUMO

The cytological findings in 7 cases of leiomyoma and 4 cases of leiomyosarcoma can be summarized as follows: For differential diagnosis of these lesions, in comparison with leiomyoma cells, leiomyosarcoma cells were found to have 1) increased minor axis diameters of the nuclei and nuclear anisokaryosis, 2) dark nuclear staining, 3) enlarged and darkly stained chromocenters, 4) dark staining and thickening of the nuclear rim, 5) enlargement of nuclear clear areas, 6) increased numbers of oval nuclei and greater pleomorphism, 7) an increase in size and number of the nucleoli, 8) a strong tendency for cell atypism, such as anisocytosis and pleomorphism. In the light of these findings, it is believed that differential diagnosis is indeed possible.


Assuntos
Leiomioma/diagnóstico , Leiomiossarcoma/diagnóstico , Neoplasias Gástricas/diagnóstico , Núcleo Celular/patologia , Citodiagnóstico , Diagnóstico Diferencial , Humanos , Leiomioma/patologia , Leiomiossarcoma/patologia , Neoplasias Gástricas/patologia
11.
Nihon Yakurigaku Zasshi ; 72(3): 313-7, 1976 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-986990

RESUMO

A study was carried out to investigate the effect of ursodesoxycholic acid and cholic acid on intestinal absorption of cholesterol-4-14C administered p.o. to lymph-fistula rats. The results indicated that within 24 hours, the labeled cholesterol detected in thoracic duct lymph of the control group was 21.0% of the administered cholesterol-4-14C, whereas the group treated with cholic acid (250 mg/kg p.o.) was found to have an increased value of 30.6% absorbed cholesterol. In comparison, the group treated with the same dose of ursodesoxycholic acid showed a decreased value of 12.1%, indicating an inhibitory effect on cholesterol absorption by the compound. This differential effect of the two compounds was also observed in a time-course study.


Assuntos
Ácido Quenodesoxicólico/farmacologia , Colesterol/metabolismo , Ácidos Cólicos/farmacologia , Absorção Intestinal/efeitos dos fármacos , Animais , Colesterol/administração & dosagem , Feminino , Isomerismo , Linfa/análise , Ratos , Ducto Torácico
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