Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pluripotent embryonic stem cells (line BLC6), when cultivated in vitro as embryoid bodies and injected subcutaneously into syngeneic mice, form teratocarcinomas consisting of embryonal carcinoma cells and differentiated tissues of all three primary germ layers. In order to study the possible effects of the mammary-derived growth inhibitor (MDGI) on the differentiation pattern of the tumors developing in the mice, BLC6 cell-derived embryoid bodies were treated in vitro for 4 days with either MDGI or a synthetic peptide composed of the C-terminal 11 amino acids of MDGI. In those tumors, significantly more differentiated neural tissue and lesser proportions of undifferentiated embryonic carcinoma cells (ECC) were found in the MDGI- and peptide-treated groups, compared with controls. The results are discussed with respect to a possible differentiation-promoting capacity of MDGI.
Virchows Arch B Cell Pathol Incl Mol Pathol 1990
PMID:Differentiation-promoting effects of mammary-derived growth inhibitor (MDGI) on pluripotent mouse embryonic stem cells. 198 2

We have cloned a novel kinase (STY) from an embryonal carcinoma cell line. Sequence analysis of the STY cDNA reveals that it shares sequence homology with serine/threonine-type kinases and yet the bacterial expression product of the STY cDNA appears to have serine-, threonine-, and tyrosine-phosphorylating activities. The predicted STY protein is highly basic and contains a putative nuclear localization signal. During differentiation, two new mRNAs were detected in addition to the embryonic transcript.
Mol Cell Biol 1991 Jan
PMID:STY, a tyrosine-phosphorylating enzyme with sequence homology to serine/threonine kinases. 198 48

Retrovirus expression in embryonal carcinoma (EC) cells is blocked at a postintegration stage of the viral life cycle, in part because of the inadequate function of the viral long terminal repeat promoter in this cell type. However, selection for retrovirus expression in EC cells has identified mutations in Moloney murine leukemia virus (M-MuLV) located in the tRNA primer-binding site (PBS) region which relieve the EC cell-specific repression. We have found that exchanging the M-MuLV proline PBS for a glutamine one in a recombinant virus permits expression in EC cells. By using the recombinant virus as a backbone, the EC cell-specific repressor-binding site (RBS) element has been mapped to M-MuLV nucleotides 147 to 174. The RBS does not require precise positioning downstream of the M-MuLV promoter and can function in either orientation and in an intron, indicating that the regulatory effect is probably at the DNA, rather than RNA, level. We also show that the RBS element can repress heterologous promoters from an upstream position. Our results indicate that the RBS acts as a silencer that its inhibitory effect is mediated by a trans-acting factor, and that the mechanism of action is probably at the level of transcription. Through in vitro binding assays we have identified a binding factor which specifically recognizes the wild-type RBS sequence (binding factor A). The binding characteristics of factor A suggest that it is a stem cell repressor which acts at the M-MuLV RBS. Our DNA-binding assays also have identified a unique binding factor (binding factor Hp) which specifically recognizes a hemimethylated form of the wild-type RBS. This factor may play a role in methylation mediated control of retrovirus expression in EC cells.
Mol Cell Biol 1991 Mar
PMID:A stem cell-specific silencer in the primer-binding site of a retrovirus. 199 87

The extent of methylation of DNA sequences upstream and within the two X-linked genes, Pgk-1 and Hprt, was analyzed in male and female somatic cells and in female embryonal carcinoma cells carrying either two active X chromosomes (Xa) or one active and one inactive X chromosome (Xi). Sites upstream and within the first intron of both Pgk-1 and Hprt were heavily methylated on the Xi in somatic cells and in embryonal carcinoma cells with an Xi. Reactivation of this Xi was accompanied by extensive demethylation of these sites. In female embryonal carcinoma cells with two active X chromosomes, one X inactivates during differentiation in culture; however, methylation did not occur during differentiation, consistent with the idea that DNA methylation does not play a role in the initiation of X inactivation but may be involved in maintaining inactivation of those genes on the Xi.
Somat Cell Mol Genet 1991 Jan
PMID:DNA methylation of two X chromosome genes in female somatic and embryonal carcinoma cells. 199 41

A clone selected from a two-cell mouse embryo cDNA library has been sequenced and identified as rig cDNA. The rig gene codes for a highly conserved nuclear protein, which may have a general role in cell growth or replication (Shiga et al.: Proc Natl Acad Sci USA 87:3594, 1990). The quantitative changes in rig mRNA were studied in blot hybridization experiments with total RNA from oocytes and early embryos. The amount and relative abundance of rig mRNA change considerably during early development. There are about 1.6 x 10(4) rig mRNA molecules in a late growth-stage oocyte; this number is reduced to about one-tenth in the ovulated egg but increases about twenty-fold during cleavage through the blastocyst stage. In F9 embryonal carcinoma cells, the relative abundance of rig mRNA is similar to that in blastocysts (about 0.1% of the mRNA population), but it is about eight-fold higher in the mouse myeloma cell line MOPC-104E. The high level of rig mRNA in late growth-stage oocytes suggests that the rig gene product may be important for overall transcriptional activity rather than DNA replication and mitosis. Alternatively, the rig protein may be a storage product of oogenesis and have a role in the initiation of development.
Mol Reprod Dev 1991 Apr
PMID:Expression of the rig gene in mouse oocytes and early embryos. 206 74

Pluripotential embryonal carcinoma cells such as those of the P19 line differentiate when exposed to retinoic acid (RA). The RAC65 cell line is a mutant clone of P19 cells selected to be RA nonresponsive. RAC65 cells carry a rearrangement affecting one of the genes encoding a nuclear retinoic acid receptor (RAR alpha). The mutant gene encodes a protein, RAR alpha', that has lost its 70 C-terminal amino acids, thus truncating the RA-binding domain. The RAR alpha' was found to be a dominant repressor of transcription from an RA-responsive target gene; however, expression of RAR alpha' was insufficient to confer RA nonresponsiveness, suggesting that RAC65 cells carry an additional mutation(s) affecting RA-induced genes.
Mol Cell Biol 1990 Dec
PMID:A dominant negative mutation of the alpha retinoic acid receptor gene in a retinoic acid-nonresponsive embryonal carcinoma cell. 217 8

Retinoic acid together with dibutyryl cyclic AMP stimulated transcription of the platelet-derived growth factor alpha-receptor gene in embryonal carcinoma cells (line F9). Processed mRNA transcripts appeared within 4 h after exposure to these agents, and functional alpha:alpha homodimers appeared within 24 h.
Mol Cell Biol 1990 Dec
PMID:Retinoic acid promotes transcription of the platelet-derived growth factor alpha-receptor gene. 217 16

The SmN protein is a component of small nuclear ribonucleoprotein particles and is closely related to the ubiquitous SmB and B' splicing proteins. It is expressed in a limited range of tissues and cell types, including several undifferentiated embryonal carcinoma cell lines and undifferentiated embryonic stem cells. The protein declines to undetectable levels when embryonal carcinoma or embryonic stem cells are induced to differentiate, producing primitive endoderm or parietal endoderm or yielding embryonal bodies. This decline is due to a corresponding decrease in the level of the SmN mRNA. The potential role of SmN in the regulation of alternative splicing in embryonic cell lines and early embryos is discussed.
Mol Cell Biol 1990 Dec
PMID:Regulated expression of the small nuclear ribonucleoprotein particle protein SmN in embryonic stem cell differentiation. 217 18

Differentiation of mouse embryonal carcinoma cells to the parietal endoderm phenotype is associated with expression of PTH-responsive adenylate cyclase. A PTH-like protein (PLP), which binds to PTH receptors and activates adenylate cyclase in classical PTH target cells was recently isolated and cloned. We assessed whether the parietal endoderm phenotype is associated with the expression of PLP or its receptor. A 1.4-kilobase PLP transcript was detected in the mouse parietal endoderm cell line PYS-2. No hybridizing transcripts were evident in undifferentiated mouse embryonal carcinoma cells PSA-1 or F9. However, differentiation of these cells to parietal endoderm, either spontaneously (PSA-1) or by treatment with retinoic acid and dibutyryl cAMP (F9), resulted in expression of the 1.4-kilobase PLP message. Undifferentiated F9 cells displayed negligible specific binding of [125I]PLP-(1-34)amide. When F9 cells were induced to differentiate to parietal endoderm, specific binding sites for [125I]PLP-(1-34)amide were expressed in parallel with PLP-responsive adenylate cyclase. These receptors, like those in classical PTH target tissues, displayed identical affinity (Kd = 5.2 nM) for bPTH-(1-34) and hPLP-(1-34)amide; with binding capacity (Bmax) of 6.6 x 10(4) sites/cell. In the presence of retinoic acid, exogenous PLP substituted for dibutyryl cAMP in a concentration-dependent fashion in promoting the differentiation of F9 cells to parietal endoderm. Thus, both PLP mRNA and PLP receptors coupled to adenylate cyclase are expressed during the differentiation of mouse embryonal carcinoma cells. Increased cAMP levels produced by autocrine stimulation of PLP receptors by PLP may contribute to differentiation of embryonal carcinoma cells into parietal endoderm.
Mol Endocrinol 1990 Apr
PMID:Expression of a parathyroid hormone-like protein and its receptor during differentiation of embryonal carcinoma cells. 217 44

Expression of the K-fgf/hst proto-oncogene appears to be restricted to cells in the early stages of development, such as embryonal carcinoma (EC) cells. When EC cells are induced to differentiate, K-fgf expression is drastically repressed. To identify cis-acting DNA elements responsible for this type of regulation, we constructed a plasmid in which cat gene expression was driven by about 1 kilobase of upstream K-fgf human DNA sequences, including the putative promoter, and transfected it into undifferentiated F9 EC cells or HeLa cells as prototypes of cells which express or do not express, respectively, the K-fgf proto-oncogene. This plasmid was essentially inactive in both cell types, and the addition of more than 8 kilobases of DNA sequences upstream of the K-fgf promoter did not lead to any increase in chloramphenicol acetyltransferase (CAT) expression. On the other hand, when we inserted in this plasmid DNA sequences which are 3' of the human K-fgf coding sequences, we could detect a significant stimulation of CAT activity. Analysis of these sequences led to the identification of enhancerlike DNA elements which are part of the 3' noncoding region of K-fgf exon 3 and promote CAT expression only in undifferentiated mouse F9 or human NT2/D1 EC cells, but not in HeLa, 3T3, or differentiated F9 cells, therefore mimicking the physiological expression of the K-fgf proto-oncogene. Similar elements are also present in the 3' region of the murine K-fgf proto-oncogene, in a region showing high homology to the human K-fgf sequences. These regulatory elements can promote CAT expression from heterologous promoters in an EC-specific manner, suggesting that they interact with a specific cellular transacting protein(s) whose expression is developmentally regulated.
Mol Cell Biol 1990 Jun
PMID:Expression of the K-fgf proto-oncogene is controlled by 3' regulatory elements which are specific for embryonal carcinoma cells. 218 89


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>