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H Esche

Publications and source records attributed to H Esche.

51 records · Page 3Linked to original sources

The adenovirus type 12 - mouse cell system: permissivity and analysis of integration patterns of viral DNA in tumor cells.

The integration patterns of persisting adenovirus type 12 (Ad12) DNA were analyzed in two Ad12-induced tumors of Balb/c and CBA/J mice and in one tumor cell line derived from an Ad12-induced retinoblastoma of C3H origin. In all three tumors the Ad12 genome was integrated colinearly and various copy numbers of viral DNA were found. Analysis of the Ad12 integration patterns revealed relatively simple offsize band patterns regardless of Ad12 copy numbers. The degree of methylation at the 5'-CCGG-3' sites in the inserted Ad12 genome was determined using the isoschizomeric restriction endonuclease pair HpaII and MspI. Methylation was rather incomplete in the primary tumor tissues but almost complete in the retinoblastoma line carried in culture for many passages. The levels of expression of the viral genome in the Balb/c tumor and in the retinoblastoma line were determined by in vitro translation of RNA isolated from these cells and selected with appropriate restriction endonuclease fragments of Ad12 DNA. In both instances the 59 K, 19 K, and 17 K proteins of the E1b region were expressed. Proteins of the E1a region appeared very faint in the size class between 22 K and 42 K. The permissivity of Ad12 and the replication of Ad12 DNA in mouse cells were investigated by blotting restricted DNA from cells soon after, and a long time after, infection and by hybridization with 32P-labeled Ad12 DNA. Neither primary mouse kidney cells nor the established L929 mouse cell line supported viral DNA replication. These results raise the question to what extent host cell factors determine Ad12 DNA replication in mammalian cells.

Adenoviruses, Human↗

The translational map of the Autographa californica nuclear polyhedrosis virus (AcNPV) genome.

We have mapped early and late viral gene products expressed in Autographa californica nuclear polyhedrosis virus ( AcNPV )-infected Spodoptera frugiperda cells by cell-free translation of virus-specific RNA which was selected by hybridization to cloned restriction endonuclease fragments of AcNPV DNA. Proteins synthesized in vitro were labeled with [35S]methionine and analyzed by SDS-polyacrylamide gel electrophoresis followed by fluorography. At least four early AcNPV -specific polypeptides were found which mapped in two regions of the genome (9-25 and 43-59 map units). These early mRNAs are also synthesized at late times in the infection cycle. Cell-free translation of restriction fragment-selected late AcNPV -specific RNA (24 h post-infection) resulted in the identification and mapping of 24 viral proteins. Curiously, the region between approximately 70 and 80 map units on the viral genome has been found silent with respect to mRNA which is translatable in a cell-free system. However, there may be RNA transcribed from this viral DNA segment.

Animals↗

Expression of early viral gene products in adenovirus type 12-infected and -transformed cells.

We have analysed early viral gene products expressed in adenovirus type 12 (Ad12)-infected cells as well as in two Ad12-transformed hamster cell lines, and Ad12-induced rat tumour cell lines by cell-free translation of virus-specific RNA which was selected by hybridization to cloned restriction endonuclease fragments of virus DNA. Proteins synthesized in vitro were analysed by one- and two-dimensional gel electrophoresis. It was found that RNA encoded by early region E1A directs the synthesis of at least eight polypeptides with apparent mol. wt. 38K, 36K, 30K, 28K, 26K, 25K, 24K and 22K. All these proteins are related to each other. E1B-specific RNA directs the synthesis of three proteins: 59K, 19K and 17K. Early region E2a codes for a 61K polypeptide which probably represents the single-strand DNA-binding protein of Ad12. RNA complementary to region E3 directs the synthesis of a 16K protein, and RNA transcribed from region E4 the synthesis of polypeptides with mol. wt. 20K, 18K and 11.5K. We have mapped a 67K polypeptide into the region within 11 to 28 map units (E2b). The analysis of proteins directed by virus-specific RNAs prepared from two Ad12-transformed hamster cell lines (T637, HA12/7) and one Ad12-induced rat tumour line (RBT12/3) showed that early regions E1 and E4 are expressed in all three Ad12-transformed cell lines. RNA transcribed from early regions E2 and E3 have been detected in lines T637 and RBT12/3. The virus RNA prepared from the Ad12-transformed cell lines directed synthesis of polypeptides with mol. wt. very similar to those of early virus proteins from infected cells. However, in all three Ad12-transformed cell lines mentioned above we have found RNAs which directed the synthesis of additional polypeptides of early regions E1 (34K) and E4 (25K, 24K) not detected in infected cells. The DNA sequence between 11 and 28 map units (coding for the 67K protein) is not expressed in the Ad12-transformed cells.

Adenoviruses, Human↗

Viral gene products in adenovirus type-2 transformed hamster cells.

I have analyzed viral gene products expressed in five adenovirus type 2 (Ad2)- cytoplasmic, viral RNA which was selected by hybridization to cloned restriction endonuclease fragments of Ad2 DNA. Proteins synthesized in vitro were analyzed by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels and compared with those directed by RNAs prepared from productively infected cells. The early regions E1 and E4 of adenovirus type 2 (Ad2) were found to be expressed in all of five Ad2-transformed hamster embryo cells lines. RNA transcribed from early region E2, which codes for the 72,000-molecular-weight (72K) DNA-binding protein was detected in cell line HE1 only, and early region E3 was expressed exclusively in cell line HE4. RNA transcribed from the region between approximately 12 and 35 map units, coding for immediate early (13.5K, 52/53K) and immediate early proteins (13.6K, 16K, 17K, 87K), as well as RNA from late genes, was not found in any of the cell lines HE1 to HE5 had electrophoretic mobilities similar to those programmed by RNA from productively infected cells.

Adenoviruses, Human↗

[Efficacy of systemic rehabilitation in patients with myocardial infarct--a 4 years' study].

Form and results of the rehabilitation of patients with myocardial infarction during and after clinical treatment are described in a 4-year-study. According to the form a system rehabilitation is concerned. It comprises a continuous course of early mobilisation during clinical treatment, immediately following group exercise treatment after clinical treatment, then a sanatory cure and a continuing life-long group training. The results are an ergometrically objectified increase of physical function which is larger than in an untrained patient and a decrease of the factor of risk, on the basis of which a high degree of occupational and social rehabilitation is gained.

Adult↗

In vitro translation of adenovirus type 12-specific mRNA isolated from infected and transformed cells.

The early and late gene products of human adenovirus type 12 (Ad12), as well as the viral proteins synthesized in an Ad12-transformed cell line, were identified by translation of viral mRNA in an in vitro protein-synthesizing system. Cytoplasmic RNA was isolated from permissive KB or nonpermissive BHK cells infected with Ad12 and from Ad12-transformed HA12/7 cells. Virus-specific RNA was selected by hybridization to Ad12 DNA covalently bound to cellulose. Viral RNA was then translated in a fractionated rabbit reticulocyte cell-free system or in wheat germ S-30 extracts. The proteins synthesized were characterized by immunoprecipitation and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels. RNA prepared from KB cells late after infection with Ad12 elicited the synthesis of most of the structural polypeptides of the virion and at least two presumably nonstructural Ad12 proteins. When viral RNA isolated early after infection of KB cells with Ad12 was translated in vitro, 10 polypeptides were observed: E-68K, E-50K, E-42K, E-39K, E-34K, E-21K, E-19K, E-13K, E-12K, and E-10K. Ad12-specific RNA was also isolated from the Ad12-transformed hamster cell line HA12/7, which contains several copies of the Ad12 genome integrated in the host genome. The RNA codes for at least seven polypeptides with molecular weights very similar to those of the early viral proteins.

Adenoviruses, Human↗

Gene expression of bacteriophage SPP1. II. Regulatory aspects.

The expression of late SPP1 genes depends on preceding SPP1 DNA replication. This is shown in nonpermissive infection with a mutant defective in DNA replication and after inhibition of DNA synthesis by HPUra. The potential for host gene expression is not significantly influenced by SPP1 infection, as evidenced by the continuation of host protein synthesis and the inducibility of glycerolphosphate dehydrogenase after infection. The involvement of a positive control element in the regulation of SPP1 gene expression is deduced from the observation that chloramphenicol prevents the synthesis of the only class of mRNA which is transcribed from the L-strand.

Bacillus subtilis↗

Gene expression of bacteriophage SPPI. I. Phage directed protein synthesis.

A total of 23 phage specific proteins (including four head and six tail proteins) could be identified after SDS polyacrylamide gel electrophoresis of extracts from phage SPP1 infected Bacillus subtilis cells. The total molecular weight of the proteins amounts to approximately 1.9 X 10(6) daltons, equivalent to the majority of the coding capacity of SPP1 DNA. It can thus be assumed that almost all SPP1 coded proteins have been identified. Protein assignments to phage cistrons were made by analysis of extracts from nonpermissive cells infected with sus-mutants. The SPP1 specified proteins can be subdivided into three groups on the basis of the time of their synthesis during the latent period. Host protein synthesis is not significantly affected by SPP1 infection. Normal expression of host genes appears to be essential for SPP1 growth.

Bacillus subtilis↗