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T A Dyer

Publications and source records attributed to T A Dyer.

46 records · Page 3Linked to original sources
PubMed1973

Nucleotide sequence analysis of the cytoplasmic 5S ribosomal ribonucleic acid from five species of flowering plants.

Broad-bean 5S rRNA labelled with (32)P was digested separately with T(1) and pancreatic A ribonucleases and the resulting oligonucleotides (20 and 18 respectively) were fractionated by two-dimensional electrophoresis. The oligonucleotides were analysed further and 32 of them have been completely sequenced. They were compared with those of 5S rRNA from dwarf bean, sunflower, tomato and rye. Sequence differences were found at both the 3'- and 5'-termini and at up to nine other positions. Most base substitutions were transitions between C and U. In common with other 5S rRNA species that have been analysed the ends of the molecule in each plant species have complementary sequences.

Autoradiography↗
PubMed1971

Characterization of cytoplasmic and chloroplast 5S ribosomal ribonucleic acid from broad-bean leaves.

Green leaves of the broad bean (Vicia faba) contain two 5S RNA components that can be separated from each other by polyacrylamide-gel electrophoresis. The major component is located in the larger subunit of cytoplasmic ribosomes, whereas the minor component occurs in the larger subunit of chloroplast ribosomes. Their electrophoretic mobilities relative to those of Escherichia coli 5S RNA (120 nucleotides) and plant 4S RNA (78 nucleotides) suggest that they consist of 118 and 122 nucleotide residues respectively. Thermal ;melting' profiles of plant cytoplasmic and chloroplast 5S RNA species at 260nm indicate the similarity of their secondary structures, not only to each other, but also to those of E. coli and mammalian 5S RNA species. The base compositions of the two plant 5S RNA species have more in common with each other than with the corresponding molecules from either E. coli or mammalian cells.

Acrylates↗
PubMed1968

Chloroplast and cytoplasmic low-molecular-weight ribonucleic acid components of the leaf of Vicia faba L.

1. A method for the extraction of plant nucleic acids and their separation on methylated-serum-albumin-kieselguhr columns is described. It is demonstrated that the characteristics of the elution profiles of material from the same source are consistently reproducible. 2. Major dissimilarities were found in the elution profiles of nucleic acids from root and from leaves of Vicia faba L. These dissimilarities were confirmed by polyacrylamide-gel electrophoresis. 3. Four distinct types of low-molecular-weight RNA were demonstrated to be present in leaves, clearly distinguished by their behaviour when chromatographed on methylated-serum-albumin-kieselguhr columns. (a) Both cytoplasmic and chloroplast ribosomes contained a low-molecular-weight RNA, and these components were distinct from each other. (b) The chloroplast possessed a unique ;soluble' RNA (i.e. RNA that is not precipitated by centrifugal forces that sediment ribosomes) which was not present in the rest of the cell. (c) A soluble component, probably transfer RNA, was found in both the chloroplasts and in the cytoplasm. 4. The components distinguishable by methylated-serum-albumin-kieselguhr column chromatography could not be distinguished by sucrose-density-gradient centrifugation.

Carbon Isotopes↗