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J S Beckmann

Publications and source records attributed to J S Beckmann.

143 records · Page 8Linked to original sources
PubMed1986

Linguistics of nucleotide sequences: morphology and comparison of vocabularies.

The concept of "words" in continuous languages devoid of blanks is introduced and an operational definition of words given. With this novel concept nucleotide sequences become object for linguistic analysis. The typical word size of the nucleotide language is found to be 3 to 5 (tri- to pentamers). Different genomes have distinct vocabularies. Comparison of these vocabularies can serve as a basis for revealing functional and evolutionary relatedness of sequences.

Bacteriophages↗
PubMed1986

Restriction fragment length polymorphism among Israeli Holstein-Friesian dairy bulls.

Israeli Holstein-Friesian dairy bulls were screened for restriction fragment length polymorphisms by hybridizing cloned DNA probes for bovine growth hormone, for chymosin, and for rat muscle beta-actin to restriction endonuclease-digested DNA immobilized on nitrocellulose filters. The population proved to be polymorphic at the growth hormone locus, with evidence consistent with the phenotypes being inherited in allelic fashion. A low level of polymorphism was also observed at one of the beta-actin gene family loci. The chymosin locus was monomorphic with the restriction enzymes utilized. The results illustrate the power of restriction fragment length polymorphism methodology in visualizing genetic variability in dairy cattle populations.

Actins↗
PubMed1983

G-418, an elongation inhibitor of 80 S ribosomes.

The mode of action of the aminoglycoside G-418 was studied in wheat-germ, cell-free translation systems programmed with rat-liver polyadenylated RNA. Incorporation of amino acids into protein was effectively inhibited by G-418 in the microM concentration range. The inhibition pattern obtained was not uniform. The synthesis of polypeptides with higher molecular weights was more inhibited than that of smaller polypeptides. An identical inhibition pattern within a similar range of concentrations was obtained with cycloheximide, a known elongation inhibitor. Translation activity was abolished when the wheat-germ 80 S ribosomes were removed and could be partially reconstructed upon addition of the ribosomes. Incubation with G-418 prior to isolation yielded ribosomes defective in their reconstruction ability. The inhibition pattern was not uniform and exhibited again the same relationship between the size of a polypeptide and the extent of inhibition of its synthesis. Therefore, we suggest that in wheat-germ, cell-free translation systems G-418 affects the 80 S ribosomes and inhibits the elongation cycle.

Animals↗
PubMed1983

Isolation and nucleotide sequence of a plant tRNA gene: petunia asparagine tRNA.

A 14.3 kb petunia genomic DNA fragment was isolated and found to contain a single tRNA gene coding for asparagine tRNA. The nucleotide sequence of the asparagine tRNA gene and its flanking regions has been determined. This gene does not contain intervening sequences nor the 3'-end CCA sequence of the mature tRNA and presents a similar overall sequence homology (70%) to both E. coli and mammalian asparagine tRNA. As in other eukaryotic tRNA genes the 5'-flanking region does not seem to contain any special sequence that could function as a regulatory element and the 3'-end is followed by a short cluster of T that may function as the transcription termination site.

Aspartate-tRNA Ligase↗
PubMed1978

Transcription and processing of intervening sequences in yeast tRNA genes.

Genes for yeast tRNATyr and tRNAPhe have been sequenced (Goodman, Olson and Hall, 1977; Valenzuela et al., 1978) which contain additional nucleotides (intervening sequences) within the middle of the gene that are not present in the mature tRNA. We have isolated precursors to rRNATyr and tRNAPhe from a yeast temperature-sensitive mutant (at the rna1 locus) which accumulates only certain precursor tRNAs at the nonpermissive temperature. The tRNATyr and tRNAPhe precursors were analyzed by oligonucleotide mapping; they each contain the intervening sequence and fully matured 5' and 3' termini. Furthermore, these precursors were used as substrates to search for an enzymatic activity which can remove the intervening sequences and religate the ends. We have shown that wild-type yeast contains such an activity, and that this activity specifically removes the intervening sequences to produce mature-sized RNAs.

Base Sequence↗
PubMed1977

Cloning of yeast transfer RNA genes in Escherichia coli.

Four thousand Escherichia coli clones containing yeast DNA inserted into the plasmid pBR313 have been isolated. Of these, 175 clones were identified as carrying yeast transfer RNA genes. The initial analysis of the inserted transfer RNA genes via the colony hybridization technique with individual radioactive transfer RNA species is reported. The data indicate that yeast transfer RNA genes are not highly clustered, although some clustering exists. In addition, it was observed that the reiteration number of different transfer RNA genes may vary extensively.

Chromosome Mapping↗
PubMed1975

DNA-RNA hybridization.

Interest in nucleic acid hybridization stems mainly from its great power as a tool in biological research. It is used in several quite distinct ways. Because of the high degree of specificity that they show, hybridization techniques can be used to measure the amount of one specific sequence within a very heterogeneous mixture of sequences. Measurements of 1/10(6)-10(7) have been recorded. In extension of this, various properties of a specific sequence can often be studied. Secondly, because the kinetics of nucleic acid hybridization are quite well understood, it can be used to characterize both a pure sequence and a very complex mixture of sequences, like the genome of a vertebrate. Thirdly, again because of its specificity, it can be used to measure homologies between different populations of nucleic acids. Lastly, in conjunction with other techniques, it can be used as a basis for the fractionation of nucleic acid populations and the purification of specific sequences. Specific examples of these applications are given, with special reference to the organization of the genome in higher eukaryotes.

Animals↗
PubMed1971

Purification and in vitro transcription of a transfer RNA gene.

A gene specifying tyrosine transfer RNA has been purified and transcribed in vitro. The purification procedure made use of two specialized transducing phages carrying the tRNA(Tyr) gene of Escherichia coli inserted into their DNA in opposite orientations. The separated heavy strands of the two phages were annealed and the single-stranded tails of the resulting hybrid were removed by digestion with Neurospora endonuclease. The size of the purified double-stranded structures was determined by electron microscopy. These isolated duplexes served as template for the in vitro transcription of tRNA(Tyr)-like molecules.

Centrifugation, Density Gradient↗
PubMed1970

In vitro transcription of a transfer RNA gene.

The Escherichia coli tRNA(Tyr) gene carried by the varphi80psu(3) + transducing phage was transcribed in vitro by DNA-dependent RNA polymerase. The enzymatically synthesized tRNA(Tyr)-like polynucleotide chains were detected by competition with purified E. coli(32)P-tRNA(Tyr) for specific hybridization sites on varphi80psu(3) + DNA. Analysis by sucrose gradient centrifugation showed the tRNA(Tyr)-like chains to possess a heterogeneous distribution with respect to sedimentation coefficients, with a broad peak around 8 S. The presence of the termination factor rho during the transcription did not significantly reduce the average size of the in vitro synthesized tRNA(Tyr)-like chains.

Bacteriophages↗
PubMedDate not supplied

Cardiac myosin binding protein C gene is specifically expressed in heart during murine and human development.

Cardiac myosin binding protein C (MyBP-C) is a substantial component of the sarcomere, with both structural and regulatory roles. The gene encoding cardiac MyBP-C in humans is located on chromosome 11p11.2, and mutations that are most predicted to produce truncated proteins have been identified in this gene in unrelated families with familial hypertrophic cardiomyopathy (FHC). To understand better the pathophysiology of FHC and with a view to the development of animal models for this disease, we have investigated by in situ hybridization the pattern of expression of the cardiac MyBP-C gene during human and mouse development using species-specific oligonucleotide probes. From 4 weeks of human development, a strong labeling of cardiac MyBP-C mRNAs was unambiguously detected in all heart compartments, and no signal could be visualized in somites. In murine embryos, from embryonic day 9.5 until birth, a strong signal was detected exclusively in the heart. Our results showed that during both human and murine development, in contrast to chicken development, the cardiac MyBP-C gene is abundantly and specifically expressed in the heart.

Animals↗