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Lyon J - - 1994
The c-myb protooncogene is the prototype of a gene family that contains two other recently described members, A-myb and B-myb. The c-myb gene encodes a transcription regulatory protein, c-Myb, that has distinct DNA-binding domain structure and binding specificity compared with unrelated transcription factors. All three members of the myb protein ...
Mohamedali K A - - 1993
Recent studies on the tissue distribution and developmental regulation of adenosine deaminase (ADA) activity in mice show that very high ADA levels exist in the murine alimentary tract (tongue, esophagus, forestomach, proximal small intestine) and at the fetal-maternal interface. To understand the role of ADA in these tissues, we measured ...
Zhang L - - 1993
This study examined the immunohistochemical expression of p53 in human oral premalignancies and squamous cell carcinomas (SCC), and analyzed the relationship between the expression of p53 and the degree of dysplasia. p53 staining was observed in 15 of the 27 oral premalignant lesions (56%), including mild dysplasia, and 7 of ...
Seneca S - - 1993
We have shown previously that c-myb expressed in the yeast S. cerevisiae mediated efficient transcriptional activation of reporter genes designed with specific Myb Recognition Elements (MRE's), confirming that this proto-oncogene is able to function as a regulator of transcription in that heterologous context. Here we show that in yeast, as ...
Lam E W - - 1993
Transcription of the B-myb gene is regulated at the G1/S boundary of the cell cycle. To begin to examine the mechanism controlling expression of this gene during the cell-cycle, a mouse B-myb 5' flanking sequence was isolated from a cosmid library and shown to promote efficiently the transcription of a ...
Ghosh D - - 1993
The Transcription Factors Database is a specialized database focusing on transcription factors and their properties. This report describes the present status of this database and developments during the past year. Within this time, the size of this database has increased by a 2799 total records, and has become accessible through ...
Sleeman J P - - 1993
c-myb has been studied intensely, but other members of the myb gene family have been largely overlooked. This paper describes the isolation and characterization of a Xenopus cDNA sequence, XAMyb, closely related to human A-myb. Xenopus provides a valuable experimental model for investigating the involvement of genes in cell proliferation, ...
Gogusev J - - 1993
Following exposure to phorbol ester (TPA), DEL cell line, a human malignant histiocytosis (MH) cell line, is able to differentiate along a macrophage phenotype and thus it provides a suitable model for analyzing the sequential and differential gene expression associated with monocyte/macrophage differentiation. C-myc, c-myb, c-fos, c-sis and c-fms expression ...
Glaser R - - 1993
Changes in the cellular immune response associated with psychological stress were studied by using an academic stress model with medical students. The authors examined the expression of 2 proto-oncogenes, c-myc and c-myb, in peripheral blood leukocytes (PBLs) obtained from medical students at the time of examinations and at a baseline ...
Schaefer A - - 1993
The effects of calcium ionophores A23187 and ionomycin on the c-myb and c-myc mRNA levels have been investigated in the Friend erythroleukemia cell line F4-6 using Northern blot analysis. Treatment of the cells with 0.5-4 microM A23187 or 1-4 microM ionomycin induced a concentration-dependent decrease in c-myb mRNA; this decrease ...
Ness S A - - 1993
The c-Myb transcription factor regulates the differentiation of immature erythroid, lymphoid, and myeloid cells, although only the latter cells become transformed by the v-myb oncogene. These are also the only cells that express the Myb-regulated gene mim-1, suggesting that Myb requires tissue-specific, cooperating factors to activate such genes. Here, we ...
Cogswell J P - - 1993
Activation of the murine c-myc promoter by murine c-Myb protein was examined in several cell lines by using a transient expression system in which Myb expression vectors activate the c-myc promoter linked to a chloramphenicol acetyltransferase reporter gene or a genomic beta-globin gene. S1 nuclease protection analyses confirmed that the ...
Olson J E - - 1993
Density-arrested BALB/c-3T3 cells stimulated to proliferate in an amino acid-deficient medium arrest in mid-G1 at a point termed the V point. Cells released from V point arrest require 6 hr to traverse late G1 and enter S phase. As data presented here show that mRNA synthesis is needed for 2-3 ...
Feghali C A - - 1993
We examined c-sis, c-myc, and c-myb proto-oncogene expression in fibroblasts cultured from affected and unaffected skin of patients with systemic sclerosis (SSc), and from healthy donor skin. Total cellular RNA from cultured dermal fibroblasts was used in slot blot analysis and scanning densitometry or phosphorimaging to quantify steady-state levels of ...
Reiss K - - 1992
We have investigated the role of the insulin-like growth factor one (IGF1) receptor and its relationship to the proto-oncogene c-myb in the growth of two types of hemopoietic cells: mitogen-stimulated human peripheral blood mononuclear cells and a human promyelocytic cell line (HL-60). Using the antisense strategy and the reverse transcriptase ...
Sala A - - 1992
The B-myb gene is expressed in many cell types at the G1/S transition of the cell cycle. Inhibition of B-myb expression in BALB/c 3T3 fibroblasts by introduction of a B-myb antisense construct greatly diminished cell proliferation, whereas constitutive expression of a human B-myb cDNA in these cells reduced their growth ...
Patel H R - - 1992
Erythropoietin stimulation of erythroid cells induces a rapid increase in c-myc and decrease in c-myb mRNA levels. The signal pathway to c-myc requires activation of protein kinase C. We now report that erythropoietin down-regulates expression of c-myb via a discrete, serine/threonine-specific phosphatase-dependent pathway. The protein kinase C-blocker H7 completely prevents ...
Mukhopadhyaya R - - 1992
Murine promonocytic leukemias involving insertional mutagenesis of the c-myb locus can be induced by replication-competent retroviruses. In previously studied promonocytic leukemic cells induced by Moloney murine leukemia virus (called MML), the provirus has been invariably integrated upstream of exons 3 or 4 and the leukemic cells expressed aberrant RNAs with ...
León Y - - 1992
The c-myb proto-oncogene encodes a transcriptional regulatory protein which is highly conserved throughout evolution. Myb has been considered to be normally restricted to hematopoietic tissues, but there are indications that this might not always be the case. The present work shows the expression of a p75 Myb oncoprotein in the ...
Yen A - - 1992
Expression of the c-myb nuclear oncogene during the cell proliferation and differentiation of HL-60 human promyelocytic leukemia cells was characterized and compared to the expression of c-fos, another nuclear oncogene with transcriptional regulatory activity. During progression through the cell cycle, the amount of c-myb protein increased. The increase was commensurate ...
Nicolaides N C - - 1992
The c-myb protooncogene, which is preferentially expressed in hematopoietic cells at the G1/S boundary of the cell cycle, encodes a transcriptional activator that functions via DNA binding. The regulatory mechanisms governing this specific pattern of expression are not fully understood, although human c-myb expression appears to be positively autoregulated via ...
Boise L H - - 1992
Alterations in expression of c-myb can have profound effects on the growth and differentiation of hematopoietic cells. Thus, it is important to understand the mechanisms by which c-myb is regulated during hematopoietic cell differentiation. Previous studies pertaining to the regulation of c-myb have been carried out with the avian and ...
Schaefer A - - 1992
Chemical inducers of the differentiation are known to cause an early transient decrease in c-myc and c-myb mRNA levels in Friend erythroleukemia cells preceding the down-regulation of c-myc and c-myb expression in the course of irreversible terminal differentiation. We therefore investigated the early effect of the potent differentiation-inducing anthracycline antitumor ...
Golay J - - 1992
Although a detailed picture is emerging about the nature of the second messengers involved in B cell activation and proliferation, little is yet known about the intracellular events taking place further downstream. The c-myb proto-oncogene, the structurally related B-myb gene, and c-myc probably code for transcription factors, have been demonstrated ...
Selvakumaran M - - 1992
The c-myb proto-oncogene is abundantly expressed in tissues of hematopoietic origin, and changes in endogenous c-myb genes have been implicated in both human and murine hematopoietic tumors. c-myb encodes a DNA-binding protein capable of trans-activating the c-myc promoter. Suppression of both of these proto-oncogenes was shown to occur upon induction ...
Danish R - - 1992
During dimethylsulfoxide (DMSO)-induced differentiation of Friend mouse erythroleukemia (MEL) cells there is a biphasic fall in c-myb mRNA levels. We have previously shown that constitutive expression of c-myb blocks differentiation. To delineate more accurately the point at which Myb blocks differentiation, MEL cells were transfected with a human c-myb construct ...
Simons M - - 1992
Smooth muscle cell (SMC) proliferation is a poorly understood process that plays a critical role in several pathological states, including atherosclerosis and hypertension. Recent work suggests that the oncogene c-myb and myosin, a ubiquitous cytoskeletal protein, may be directly involved in this process. We have used antisense nonmuscle myosin heavy ...
Brown K E - - 1992
Previously we have shown that bovine vascular smooth muscle cells (SMCs) express c-myb mRNA (Reilly, C. F., Kindy, M. S., Brown, K. E., Rosenberg, R. D., and Sonenshein, G. E. (1989) J. Biol. Chem. 264, 6990-6995). Here we have characterized changes in the low level of c-myb mRNA expressed in ...
Bosselut R - - 1992
The members of the c-myb proto-oncogene family encode sequence-specific transcriptional activators. In T cells, expression of c-myb and the related B-myb gene is induced following mitogenic stimulation. Using a purified recombinant protein, we report here that the human T cell lymphotropic virus type 1 (HTLV-1) LTR contains six specific binding ...
Boise L H - - 1992
A differentiation resistant subclone of HL-60, DMSOr, was removed from the selective pressure of dimethyl sulfoxide and characterized with a new stable phenotype of reversible differentiation. DMSOr cells, when treated with 1.25% dimethyl sulfoxide, differentiated in a manner similar to the parental HL-60 with respect to morphological changes, increase in ...
Goldman J - - 1992
We have explored the RNA oncogene expression by three human acute lymphoblastic leukemia lines, NALM-6, MOLT-3, and REH. We compared such expression with that of normal human lymphocytes. Marked differences in the RNA expression of the third exon of c-myc, v-myb, v-Hras, N-ras, v-fes, and v-fos were found. We noted ...
Barletta C - - 1992
We have detected the expression of the MYB proto-oncogene in ovarian cancer. This oncogene was thought to be expressed in a tissue-specific manner in cells of hematopoietic lineage. Total RNA from three established cell lines and four human primary ovary cancers was examined by Northern and Southern blot, RNAse protection, ...
Nicolaides N C - - 1991
The nuclear proto-oncogene c-myb is preferentially expressed in lymphohematopoietic cells, in which it plays an important role in the processes of differentiation and proliferation. The mechanism(s) that regulates c-myb expression is not fully understood, although in mouse cells a regulatory mechanism involves a transcriptional block in the first intron. To ...
Burk O - - 1991
The oncogene v-myb and its cellular progenitor c-myb encode nuclear, DNA binding phosphoproteins that are thought to regulate the expression of myb-responsive genes during myeloid differentiation. To identify such myb-regulated genes, and to explore the mechanisms by which v-myb affects their expression, we have established a conditional expression system for ...
Reiss K - - 1991
The protooncogene c-myb is the cellular equivalent of the viral transforming oncogene v-myb. When human c-myb is constitutively expressed in Balb/c3T3 cells it abrogates their absolute requirement for insulin-like growth factor 1 (IGF-1). We show now, in two different cell lines, that the constitutive expression of the protooncogene c-myb causes ...
Overbeeke C J - - 1991
This article reports an experiment on expressing the behavioural meaning of designed objects. Can a designer express the taste of a desert in the form of its packaging and can consumers match these forms when tasting the desserts? Analysis of responses of 12 adults indicates positive answers to these questions.
Reiss K - - 1991
The B-myb cDNA has extensive sequence similarities to the c-myb proto-oncogene, but, at variance with c-myb, it is expressed in cells other than hematopoietic cells. In this paper, we show that (1) B-myb is expressed in mouse, human, and hamster fibroblasts; (2) B-myb mRNA levels are growth-regulated in both fibroblasts ...
Ruiz-Ruano A - - 1991
Changes in the dynamic of expression of polypeptides following the differentiation from infective trypomastigotes to multiplicative amastigote forms of Trypanosoma cruzi were mapped by two-dimensional gel electrophoresis and quantitatively analyzed by laser densitometry. Following the differentiation from trypomastigotes to amastigotes the expression of the polypeptides 212, 183, 176, 149, 50-55, ...
Schuur E R - - 1991
Previous findings from this laboratory (Kim & Baluda, 1988) have shown that the proto-oncogenes ETS, FPS, MHT (RAF), MYC and REL are expressed in avian myeloblastosis virus (AMV)-transformed cells, whereas the MYB gene is repressed. In this study five different chicken hematopoietic tissues which contained varying concentrations of target cells ...
Melani C - - 1991
Steady-state mRNA levels of the protooncogene c-myb were measured by Northern blot analysis in the human colon carcinoma cell lines LoVo, the doxorubicin-resistant derivative LoVo/Dx, Colo 205, and HT 29. Overexpression of c-myb mRNA was detected in the Colo 205 cell line, probably because of gene amplification, while in human ...
Metz T - - 1991
A non-leukemogenic version of the v-myb oncogene causes in vitro transformation of avian myeloblasts, which are dependent on chicken myelomonocytic growth factor (cMGF). We have shown that this version of v-myb, when combined with the erythroleukemia-inducing v-erbB oncogene, is capable of causing a mixed myeloid and erythroid leukemia. Myeloid leukemic ...
Zhang X K - - 1991
3'[3-(2-Chloroethyl)-3'nitrosoureido]-3'-deoxythymidine (3'-CTNU), a chloroethylnitrosourea analog of thymidine, is a potent antineoplastic agent against murine leukemia L1210. In this study, we have examined the effects of 3'-CTNU on cellular oncogene (proto-oncogene) expression. We found that the expression of the c-myb proto-oncogene was dramatically enhanced in a concentration- and time-dependent manner by ...
Valtieri M - - 1991
These studies aimed to determine the expression and functional role of c-myb in erythroid progenitors with different cycling activities. In the first series of experiments the erythroid burst-forming unit (BFU-E) and colony-forming unit (CFU-E) populations from adult peripheral blood (PB), bone marrow (BM), and embryonic-fetal liver (FL) were treated with ...
Desbiens X - - 1991
We have described the expression of three nuclear protooncogenes, c-myc, c-myb and c-ets-1 during feather morphogenesis in the chick embryo. In parallel with the expression patterns obtained by in situ hybridization, we have mapped the spatial distribution of S-phase cells by monitoring the incorporation of 5-bromodeoxyuridine. We do not detect ...
Tsuda H - - 1991
The signal transduction system of erythropoietin (Epo) and the accompanying molecular control mechanism of proliferation and differentiation of erythroid progenitors remains largely unknown. In this study, the effect of Epo on the expression of nuclear oncogenes was investigated in two murine cell lines which respond to the hormone in different ...
Travali S - - 1991
The proto-oncogene c-myb, whose expression is usually limited to cells of the hematopoietic lineages, can be expressed in fibroblasts if placed under the control of a constitutive promoter, such as the simian virus SV40 early promoter. 3T3 cells carrying a constitutively expressed human c-myb were found to grow in 1% ...
Punyammalee B - - 1991
We assayed in the yeast S. cerevisiae the transcriptional transactivation activity of the c-myb products encoded by a normal thymus cDNA and of an aminoterminally truncated version of it (minus 58 amino acids) corresponding to the cDNAs isolated from lymphoma and leukemia cells from different origins. Both proto-oncogene products were ...
Sureau A - - 1991
We have previously reported evidence suggesting that intermolecular recombination events are involved in the tissue specific expression of the c-myb proto-oncogene in chicken. We show in this paper that recombined c-myb mRNA species are also expressed in human thymic cells, therefore indicating that intermolecular recombination of coding sequences occurs in ...
Furukawa Y - - 1990
The product of the cdc2 gene, designated p34cdc2, is a serine-threonine protein kinase that controls entry of eukaryotic cells into mitosis. Freshly isolated human T lymphocytes (G0 phase) were found to have very low amounts of p34cdc2 and cdc2 messenger RNA. Expression of cdc2 increased 18 to 24 hours after ...
Evans J L - - 1990
The function of c-Myb protein was revealed by transfecting an expression vector containing the entire c-Myb protein-coding sequence into the murine CTLL-2 T-cell line. Expressions of high levels of c-Myb protein did not alter the expression of several T-cell markers, c-fos mRNA expression, responses to interleukin-2, and growth characteristics of ...
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