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A M Colberg-Poley

Publications and source records attributed to A M Colberg-Poley.

32 records · Page 2Linked to original sources
PubMed1988

Coding sequence and expression of the homeobox gene Hox 1.3.

We have characterized Hox 1.3 (previously described as m2), a murine homeobox-containing gene, which is a member of the Hox 1 cluster located on chromosome 6. A cloned cDNA was isolated from an Okayama-Berg library generated from the chemically transformed cell line MB66 MCA ACL6. The protein sequence of 270 amino acids was deduced from the nucleotide sequence of an open reading frame containing the homeobox. The open reading frame is interrupted at the genomic level by a 960 bp intron and is organized in two exons. The Hox 1.3 protein was found to contain extensive sequence homology with the murine homeodomain protein Hox 2.1, which is encoded on chromosome 11. There are two homology with the regions in the first exon, i.e. a hexapeptide conserved in many homeobox-containing genes and the N-terminal domain, which was found to be homologous only to Hox 2.1. Furthermore, in exon 2 the homologies of the homeodomain regions are extended up to the carboxy terminus of Hox 1.3 and Hox 2.1. During prenatal murine development, maximal expression of Hox 1.3 is observed in 12-day embryonic tissue. The two transcripts carrying the Hox 1.3 homeobox are 1.9 kb and about 4 kb in length. An abundant Hox 1.3-specific 1.9 kb RNA is also found in F9 cells which were induced for parietal endoderm differentiation, whereas F9 teratocarcinoma stem cells do not stably express this specific RNA. Induction of the transcript occurs immediately after retinoic acid/cAMP treatment and the RNA level remains high for 5 days. Thus, the kinetics are different from the previously described homeobox transcripts Hox 1.1 and Hox 3.1. Interestingly, by analogy to the F9 cell system a negative correlation between transformation and Hox 1.3 expression is observed in 3T3 fibroblasts also. Untransformed 3T3 cells carry abundant 1.9 kb Hox 1.3 RNA, whereas the methylcholanthrene-transformed MB66 and LTK- cells or 3T3 cells transformed by the oncogenes src, fos or SV40 T antigen express only low levels.

Amino Acid Sequence↗
PubMed1987

Post-transcriptional regulation of a murine homeobox gene transcript in F9 embryonal carcinoma cells.

A 2.4 kb RNA encoded by the murine Hox 1.1 (m6) homeobox gene is induced when F9 stem cells are differentiated with retinoic acid and dibutyryl cyclic AMP. The regulation of Hox 1.1 expression was probed by using cycloheximide, an inhibitor of protein synthesis. Production of the Hox 1.1 RNA in differentiating F9 cells was not blocked by treatment with cycloheximide, indicating that new protein synthesis is not required for its induction. On the contrary, this transcript was detected in F9 stem cells treated with cycloheximide, anisomycin, or emetine alone. Nuclear transcription assays indicated that the Hox 1.1 gene was transcribed in F9 stem cells and that the rate of transcription did not change early in the differentiation of F9 cells. These observations indicate that the induction of Hox 1.1 transcripts in F9 stem cells during differentiation is not regulated at the level of transcription initiation but results from stabilization of the transcript.

Animals↗
PubMed1986

Sequential expression of murine homeo box genes during F9 EC cell differentiation.

We have isolated and characterized a previously unknown member of the murine homeo box family. The new locus, m31, is located on chromosome 15 and is more homologous to sequences contained in the Drosophila homeotic gene, Antp, than to any other known murine homeo box. We show that this gene encodes a 2.7 kb mRNA which is expressed during mouse embryogenesis and during differentiation of F9 teratocarcinoma cells into parietal endoderm cells. The transcript appears late in this differentiation process and is most abundant at a time when the F9 cells begin to express tissue-specific markers and the expression of another murine homeo box gene, m6, has decreased.

Animals↗
PubMed1986

Genetic and cytogenetic localisation of the homeo box containing genes on mouse chromosome 6 and human chromosome 7.

Probes from the m6 homeo box cluster were mapped to mouse chromosome 6 by somatic cell genetics, in situ hybridisation, and by a Mus spretus--Mus musculus backcross mapping system. In addition, the testis-specific homeo box containing cDNA, clone, HBT-1, has been mapped using the same back-cross system and the B X D recombinant inbred strain set. Close genetic and physical linkage between the m6 cluster and HBT-1 was demonstrated, positioning these sequences to the same local cluster of homeo box containing genes. The map location of this cluster between IgK and Tcrb coincides with the morphological mutation hypodactyly (Hd). Synteny has been observed between a region of mouse chromosome 6 and the long arm of human chromosome 7 encompassing the markers Cpa, Tcrb and Try-1. Here we localise human sequences hybridising to the mouse m6 probes to the short arm of chromosome 7, breaking the region of synteny.

Animals↗
PubMed1985

Clustered homeo boxes are differentially expressed during murine development.

A murine homeo box (m6-12) known to be expressed during differentiation of embryonal carcinoma cells lies within a cluster of homeo boxes located in 30 kilobase pairs of genomic DNA. We have established the organization of the boxes within this complex, as well as the nucleotide sequence of a second box, m5-4. Similar to the m6-12 box, expression of novel m5-4 transcripts is induced upon differentiation of embryonal carcinoma cells. Transcripts of genes containing m6-12 were found in embryonic tissue during almost all stages of prenatal development studied, whereas expression of m5-4 was detected only in 12 day embryonic tissue. Finally, we have described the differential expression of these homeo-box-containing regions in various adult tissues.

Amino Acid Sequence↗
PubMed1984

Analysis of two potential shuttle vectors containing herpes simplex virus defective DNA.

Two potential shuttle vectors which contained the identical herpes simplex virus type 1 (HSV-1) defective particle DNA (dDNA), but prokaryotic DNA of different origins, were examined for their stability when propagated in eukaryotic cells, and for their efficiency as shuttle vectors. Each chimeric molecule contained a 9.5 kilobase-pair (kb) EcoRI fragment (HSV12-7) representing a single unit of a class I HSV-1 dDNA. This dDNA was cloned into the bacteriophage lambda (lambda) vector lambda gtWES X lambda B' to create a 45.3 kb chimeric molecule (lambda gtWES::12-7), and into the plasmid vector pBR325, resulting in a 15.5 kb recombinant DNA molecule (pBR325::12-7). Each of these DNA molecules was transfected independently into African green monkey kidney cells which were then infected with wild-type HSV-1 helper virus. Both chimeric molecules were replicated and packaged into HSV-1 virions. However, regions of the lambda gtWES::12-7 chimeric DNA were rapidly deleted and rearranged, whereas the plasmid/HSV-1 DNA molecules were less rearranged. No intact lambda gtWES::12-7 DNA was recovered from HSV-1 virions as detected by infectivity of in vitro packaged DNA. However, pBR325::12-7 DNA isolated from HSV-1 virions was able to transform E. coli to ampicillin resistance. These results suggest additional considerations when designing single units of HSV-1 dDNA for use as vectors to accommodate large fragments of DNA.

Animals↗
PubMed1983

Characterization of the herpes simplex virus type 1 glycoprotein D mRNA and expression of this protein in Xenopus oocytes.

We have identified and characterized a 3.0 kilobase (kb) mRNA containing coding sequences of the herpes simplex virus type 1 (HSV-1) glycoprotein D (gD) gene. The synthesis of this 3.0 kb mRNA was unaffected by the presence of cytosine arabinoside, but was made in greatly reduced amounts in cells infected with HSV-1 in the presence of cycloheximide: it was, therefore, classified as an early mRNA. By nuclease protection experiments, it was found that the 3.0 kb mRNA is unspliced and, further, that it is 3' co-terminal with a smaller 1.6 kb early mRNA which is transcribed from a DNA sequence 3' to the gD coding sequence. We describe the use of the Xenopus laevis oocyte system to produce HSV-1 gD in vitro. Oocytes injected with mRNA isolated from HSV-1-infected Vero cells synthesized gD, which was identified by immunoprecipitation. Injection of a plasmid clone containing the HSV-1 BamHI J fragment (0.89 to 0.93 map units) into the nuclei of Xenopus oocytes also resulted in synthesis of gD.

Animals↗
PubMed1983

A lambda library of Herpes simplex virus type 1 (KOS) DNA fragments obtained by partial digestion with Sau3A.

Large fragments of Herpes simplex virus type 1 (HSV-1, strain KOS) DNA were produced by partial cleavage with Sau3A and inserted into a phage lambda BamHI vector. Recombinant phage (lambda KOS) DNA molecules were isolated and characterised. The final collection of phage recombinants contains partially overlapping inserts, which represent most of the HSV-1 genome. Restriction enzyme analysis of many independent clones containing Us sequences revealed sequence polymorphism in two specific regions.

Bacteriophage lambda↗
PubMed1981

Involvement of an early human cytomegalovirus function in reactivation of quiescent herpes simplex virus type 2.

We have previously described an in vitro system in which the function lacking for herpes simplex virus type 2 (HSV-2) replication can be induced by human cytomegalovirus (HCMV). The mechanism of this reactivation of quiescent HSV-2 by HCMV has been further defined. The HCMV function(s) responsible for HSV-2 stimulation was examined temporally, and the fraction of cells in quiescent cultures producing HSV-2 after superinfection was determined. Using independent biological, genetic and molecular techniques we have made the following observations. (i) As early as 12 h after HCMV superinfection, HSV-2 RNA was expressed in latently infected cells. (ii) At 24 h after HCMV superinfection, a time when newly synthesized HCMV was not yet apparent, infectious HSV-2 was produced by reactivated cultures. (iii) Four HCMV temperature-sensitive mutants, which are DNA-negative at nonpermissive temperature and represent four different complementation groups, induced reactivation of HSV-2 at 39.5 degrees C. (iv) Early after HCMV superinfection, 1.6% of quiescent cells could be induced to transcribe HSV-2 information. (v) Early after HCMV superinfection, 0.3% of cells in the quiescent cultures could be induced to yield infectious HSV-2. The finding that a significant interaction can occur between HCMV and quiescent HSV-2 in an in vitro model is noteworthy in light of the knowledge that both of these herpesviruses often reside simultaneously in the human host.

Cell Line↗
PubMed1979

Reactivation of herpes simplex virus type 2 from a quiescent state by human cytomegalovirus.

The ability of human cytomegalovirus to stimulate replication of herpes simplex virus type 2 (HSV-2) was examined. The system used involved HSV-2-infected human embryonic lung cells under conditions (39.5-40 degrees C) in which HSV-2 remains undetectable. Reactivation of HSV-2 was maximal and persisted for the longest duration when cultures were superinfected with 0.02 plaque-forming unit of human cytomegalovirus per cell. Infectious HSV-2 appeared 2 days after superinfection with human cytomegalovirus and ranged from 10(2) to 10(6) plaque-forming units per culture. Virus reactivated from these cultures was neutralized by rabbit immune serum produced against HSV-2. The specificity of this interaction was demonstrated by various criteria: production of HSV-2 was not observed in cultures treated with mock infecting fluid, and inactivation of human cytomegalovirus by heat, ultraviolet irradiation, or immune serum prior to superinfection eliminated its ability to induce HSV-2 replication. These results sugges that interaction between these two human herpesviruses may be of importance in herpesvirus latency in vivo.

Cells, Cultured↗
PubMedDate not supplied

Structural analysis of murine genes containing homoeo box sequences and their expression in embryonal carcinoma cells.

The presence of homoeo box sequences in the genomes of vertebrates has suggested that these metazoans possess the equivalent of the homoeotic genes that have a key role in regulating the development of the fruitfly Drosophila melanogaster. We report here that a novel murine homoeo box-containing gene is expressed in embryonal carcinoma stem cells. Transcripts of the sequences that flank the homoeo box of this gene are found in these cells before and after induced differentiation, whereas a specific transcript that seems to contain the homoeo sequence is only present after differentiation.

Animals↗