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B M Paterson

Publications and source records attributed to B M Paterson.

At least 55 records · Page 3Linked to original sources
PubMed1986

Isolation of a non-muscle myosin heavy chain gene from Acanthamoeba.

We have isolated a non-muscle myosin heavy chain gene from Acanthamoeba castellanii using as a heterologous probe a sarcomeric myosin heavy chain gene from Caenorhabditis elegans. The amoeba genomic clone has been tentatively identified as containing a myosin II heavy chain gene based on hybridization to a 5300-nucleotide RNA species, hybrid selection of a mRNA encoding a 185-kDa polypeptide, specific immunoprecipitation of this polypeptide with antiserum to myosin II, and an exact match between the DNA sequence and a carboxyl-terminal myosin II peptide previously sequenced by protein chemical methods (Côté, G.P., Robinson, E.A., Appella, E., and Korn, E. D. (1984) J. Biol. Chem. 259, 12781-12787). We also sequenced a region of the gene whose deduced amino acid sequence shows strong homology with that region of muscle myosins which is thought to be involved in nucleotide binding. These results indicate that the amoeba genomic clone contains at least 90% of the coding information for the 185-kDa heavy chain polypeptide and that the bulk of the gene contains very little intron DNA. Genomic blots of amoeba DNA probed with a portion of this myosin gene indicate the presence of additional highly related sequences within the amoeba genome.

Amino Acid Sequence↗
PubMed1985

Molecular cloning of a gene sequence regulated by nerve growth factor.

Nerve growth factor (NGF) is essential for the development and differentiation of sympathetic or sensory neurons. A complementary DNA was cloned that corresponds to a gene sequence induced more than 50-fold in a cultured target cell line of pheochromocytoma cells (PC12 cells) 5 hours after the addition of NGF. The induced messenger RNA encodes a 90,000-dalton polypeptide that may represent one of the primary events in NGF-induced differentiation of neurons.

Actins↗
PubMed1985

Nucleotide sequence of the chicken cardiac alpha actin gene: absence of strong homologies in the promoter and 3'-untranslated regions with the skeletal alpha actin sequence.

The entire nucleotide sequence of the chicken cardiac alpha-actin (CC alpha A) gene has been determined. This is the first complete sequence of a cardiac actin gene that includes the promoter region, cap site, all the introns, and the polyadenylation site. The gene contains six introns, five of which interrupt the coding region at amino acids (aa) 41, 150, 204, 267, and 327. The first intron is in the 5'-noncoding region and is 438 bp in length. The CC alpha A gene encodes an mRNA of approx. 1400 bp with 5'- and 3'-untranslated region of 59 and 184 nucleotides (nt), respectively. Like the chicken skeletal alpha-actin gene, the CC alpha A gene has the codon for the aa cysteine between the initiator ATG and the codon for the N-terminal aspartic acid residue of the mature protein. There are no strong homologies (less than 13 consecutive nt) in the promoter or 3'-untranslated regions between the CC alpha A and chicken skeletal alpha-actin genes even though both are expressed in skeletal muscle during development. However, the 3'-untranslated region of the CC alpha A gene demonstrates significant sequence homology (76% over a 200-nt region) with the same region in the partial sequence of the human cardiac gene. The conservation of these sequence homologies between identical isoforms rather than the different alpha actin genes suggests these conserved regions may have a role in regulation rather than tissue-specific expression, as previously proposed.

Actins↗
PubMed1985

The chicken vimentin gene: aspects of organization and transcription during myogenesis.

The intermediate filament gene vimentin exists in a single copy in the chick haploid genome. However, it exhibits the curious property of producing at least three functional vimentin mRNA transcripts in vivo through the differential utilization of multiple polyadenylylation sites. According to one group in erythroid cells there may be a tissue-specific utilization of one of these poly A addition sites. The chicken and hamster vimentin genes exhibit remarkable nucleotide sequence homology both within coding and 3'-noncoding regions (82%). This nucleotide homology extends both to the size and juxtaposition of exons. With the noted exception of valine, even the frequency of codons utilized is strongly conserved across the widely different species. Of course, this strong homology at the DNA level extends to an amino acid homology of 92% between vimentins and 65% between related proteins in the same species.

Amino Acid Sequence↗
PubMed1984

Acanthamoeba myosin IA, IB, and II heavy chains are synthesized in vitro from Acanthamoeba messenger RNA.

Addition of a myosin IB polyclonal antibody, which reacts with the heavy chains of both myosins IA and IB, to the [35S]methionine-labeled proteins synthesized in vitro using Acanthamoeba messenger RNA specifically immunoprecipitated radioactive polypeptides that migrated on sodium dodecyl sulfate-polyacrylamide gels exactly with the heavy chains of purified myosins IA and IB. A myosin II polyclonal antibody specifically immunoprecipitated a radioactive polypeptide which migrated exactly with the heavy chain of myosin II. These results provide strong evidence that Acanthamoeba myosins IA, IB, and II are separate gene products and that the purified proteins contain native, undegraded heavy chains. These results are especially important for myosins IA and IB, because they possess unusually small heavy chains for myosins.

Amoeba↗
PubMed1984

alpha-Cardiac actin is the major sarcomeric isoform expressed in embryonic avian skeletal muscle.

A primer extension assay that is diagnostic for the messenger RNA's (mRNA's) transcribed from the beta-cytoplasmic, alpha-cardiac, and alpha-skeletal actin genes of the chicken was used to measure the mRNA levels for these actin isoforms. Measurements were made in chicken breast muscle during myogenesis in vivo and in vitro. alpha-Cardiac actin mRNA accounts for more than 90 percent of the sarcomeric actin transcripts expressed in avian embryonic breast muscle. Five weeks after hatching, alpha-skeletal actin mRNA is the only detectable sarcomeric actin transcript.

Actins↗
PubMed1984

Expression and regulation of chicken actin genes introduced into mouse myogenic and nonmyogenic cells.

We have introduced the chicken genes for cytoplasmic beta-actin, cardiac alpha-actin, and skeletal alpha-actin into C2 cells, a murine myogenic cell line, and into L cells by using the simian virus 40-derived vector PSV2 -gpt. In each selection, the entire population of transformed cells was analyzed for the expression and regulation of the actin genes by nuclease S1 assay and primer extension. This was compared to the expression of the vector marker Eco-gpt. The beta-actin gene is transcribed accurately and efficiently both in L-cells and in undifferentiated C2 cells. In fused C2 cells, beta-actin transcripts decrease significantly in parallel with the endogenous level of mouse beta-actin mRNA. Eco-gpt RNA levels remain essentially constant during myogenesis. The alpha-actin genes are correctly expressed at low levels in L cells but at significantly higher levels in the C2 cell background. Unlike the endogenous mouse alpha-actin gene, this level of expression does not change measurably with myogenesis. The skeletal alpha-actin gene is expressed poorly in pre- and post-fusion C2 cells, displaying no induction with differentiation. These results suggest that the tissue specificity of expression is maintained but the pattern of gene regulation for the sarcomeric actins is not. Factors in addition to the sequences flanking these genes are important for modulating gene expression during development. The decrease in the levels of beta-actin RNA during C2 cell differentiation provides a model system in which to study gene repression during development.

Actins↗
PubMed1983

Vimentin gene expression during myogenesis: two functional transcripts from a single copy gene.

We have previously reported that a single vimentin gene is present in the chicken genome (22). In vivo transcription of this gene yields two distinct classes of mRNA's (approximatley 2200 and-2500 nts) generated through the possible differential utilization of polyadenylylation sites. In this report we demonstrate that 1) both transcripts are functional in vitro and direct the cell-free synthesis of the vimentin polypeptide, as judged by two dimensional gel analysis; 2) three of the four possible adenylylation signals indicated in the sequence of the gene are utilized in vivo as determined by S1 analysis; 3) furthermore, these adenylylation sites are utilized identically in all tissues of the chicken examined; 4) the adenylylation site closest to the body of the message is apparently not used as judged by the S1 conditions employed in the assay. Levels of vimentin mRNA decrease in different tissues of the chicken during the embryonic to adult transition. There is no evidence for a tissue specific or developmentally regulated pattern of expression for either of the two vimentin transcripts. The same pattern of vimentin mRNA expression is seen in all tissues examined, only the level of expression is altered.

Aging↗
PubMed1983

Methods utilizing cell-free protein-synthesizing systems for the identification of recombinant DNA molecules.

Herein we outline three methods that, when coupled with cell-free protein synthesis, permit the identification of recombinant DNA molecules encoding specific polypeptides. RNAs enriched by fractionation on methylmercury hydroxide agarose gels are used to prepare sequence-specific probes. Recombinant DNA clones thus identified are further characterized as to their encoded polypeptides by either hybrid selection or hybrid arrest of translation.

Actins↗
PubMed1983

Transcriptional mapping of two yeast genes coding for glyceraldehyde 3-phosphate dehydrogenase isolated by sequence homology with the chicken gene.

Homology between the coding regions of the chicken and yeast glyceraldehyde 3-phosphate dehydrogenase (GAPDH) genes was directly demonstrated by the hybridization of a cDNA clone coding for GAPDH in the chicken with EcoRI-digested yeast DNA. A yeast EcoRI fragment library in bacteriophage lambda was screened using the chicken cDNA plasmid as probe, and two recombinant phages were isolated, each one containing a different GAPDH gene. The initiation and termination sites for the GAPDH mRNA were localized for the two different GAPDH genes and compared to those of other yeast genes. Measurements of the relative mRNA levels for the two genes show that both genes are transcribed at about the same level when yeasts are grown on glucose media.

Animals↗
PubMed1983

Characterization of the chicken vimentin gene: single copy gene producing multiple mRNAs.

Genomic clones and cDNA plasmids were isolated for the intermediate filament protein vimentin from chicken. The identity of the various clones was determined both by mRNA selection [Paterson, B. M. & Roberts, B. E. (1981) in Gene Amplification and Analysis, Structural Analysis or Nucleic Acids, eds. Chirikjian, J. G. & Papas, T. S. (Elsevier, North Holland), Vol. 2, pp. 418-435] and nucleotide sequence analysis. Restriction analysis, hybridization data, and heteroduplex studies confirmed that all of the genomic isolates contained overlapping fragments of an identical vimentin gene. No evidence for the existence of a second vimentin gene could be found by a Southern analysis either by using coding fragments from the purified vimentin gene or by using cDNA plasmids as probe. Likewise, copy-number experiments verified that the vimentin gene was present only once in the haploid chicken genome. However, in a RNA blot analysis, at least two equally abundant vimentin mRNA species of approximately 2,200 and 2,500 nucleotides in length were detected in all RNAs tested. Sequence analysis revealed that the vimentin gene contained two sets of tandem polyadenylylation sites, 249 and 532 nucleotides downstream from the stop codon for protein synthesis. It is proposed that the larger mRNA species arise because of complete transcription of the 3'-end of the vimentin gene (560 nucleotides of 3' nontranslated sequence), whereas the smaller mRNA species terminate after the first set of polyadenylylation sites.

Animals↗
PubMed1982

A short interspersed repetitive element found near some mouse structural genes.

We have isolated and characterized a family of interspersed repetitive elements which make up about 1% of the mouse genome. The elements represent a group of homologous but non-identical units about 400 bp in length. Individual members of the family show considerable divergence from one another. The spacial relationships between members of the family and a number of other identified mouse sequences including structural genes have been determined; these elements are found on the 5' as well as 3' sides of various genes at distances ranging from less than 1 to 7.5 kilobases (Kb). The sequences are present in the DNA of all species of Mus. Related sequences are present in the rat genome at a repetition frequency similar to that in the mouse genome. A partial sequence of one member of the family is presented.

Animals↗
PubMed1982

Neurotensin stimulates exocytotic histamine secretion from rat mast cells and elevates plasma histamine levels.

1. Neurotensin stimulated histamine release and granule extrusion when applied to isolated rat peritoneal mast cells. 2. This secretory response was prevented by the removal of calcium or energy and was not accompanied by the release of lactic dehydrogenase. 3. The secretory response produced by neurotensin was prevented by prior treatment of mast cells with cromoglycate. 4. The intravenous injection of neurotensin into anaesthetized rats produced a rapid and significant increase in the level of blood histamine that was dependent upon the dose of neurotensin. 5. Treatment of rats with compound 48/80, 24 hr before neurotensin, abolished the elevation in blood histamine caused by neurotensin. The intravenous injection of cromoglycate 1-2 min before neurotensin greatly reduced the response to neurotensin. 6. The intradermal injection of neurotensin (0.03-30 p-mole) increased capillary permeability in rats pre-treated intravenously with Evans Blue. This response was abolished by the antihistamine, diphenhydramine. Increasing the dose of neurotensin to 300 p-mole partially overcame this inhibition by diphenhydramine. 7. Our results demonstrate that neurotensin can elicit an exocytotic secretory response from isolated rat peritoneal mast cells and elevate histamine levels in blood. It is suggested that some of neurotensin's physiological effects may be due to stimulation of mast cell secretion.

Animals↗
PubMed1982

Stimulus-secretion coupling in rat mast cells: inactivation of extracellular calcium dependent secretion.

1. Stimulation by compound 48/80 of mast cells deprived of Ca failed to release histamine. Secretion of histamine was elicited from such cells by the subsequent introduction of Ca. 2. Histamine secretion declined as the interval between stimulation by compound 48/80 and the introduction of Ca increased. This decline is called inactivation. 3. The addition of the ionophore, A23187, with Ca restored maximum histamine secretion overcoming inactivation. 4. Increasing the concentration of Ca introduced after stimulation, from 2 to 8 mM, or to 20 mM reduced the amount of histamine released. This reduction was proportional to the interval between stimulation and the introduction of Ca. The addition of A23187 with the higher concentrations of Ca fully restored histamine secretion. 5. Stimulation of mast cells in Ca-free media by the secretagogues polymyxin B or bradykinin, and the subsequent introduction of Ca, resulted in a similar inactivation or decline in histamine release. 6. Mast cells inactivated by compound 48/80 stimulation in Ca-free media showed no increase in histamine release when the secretagogues polymyxin B plus Ca or bradykinin plus Ca were added. However, when A23187 plus Ca was added, a full secretory response was obtained. 7. It is suggested that the process of inactivation involves time-dependent change in the Ca permeability of the mast cell membrane. The concentration of introduced Ca is suggested to influence the regulation of this permeability.

Animals↗
PubMed1979

Efficient translation of prokaryotic mRNAs in a eukaryotic cell-free system requires addition of a cap structure.

In this and the accompanying paper we demonstrate that certain prokaryotic mRNAs, when modified at their 5'-termini with a cap structure, are translated in a eukaryotic cell-free protein synthesising system as efficiently as, or more efficiently than, eukaryotic mRNAs. Apparently, the prokaryotic mRNA contains all the information necessary for efficient recognition and initiation by eukaryotic translational components, except for the cap structure.

Base Sequence↗