Resuspension Buffer for Plant Ribosomes

Ribosome-inactivating proteins (RIPs) are a class of cytotoxic enzymes that can inhibit protein translation by depurinating rRNA. Most plant RIPs are synthesized with a leader sequence that sequesters the proteins to a cell compartment away from the host ribosomes. However, several rice RIPs lack these signal peptides suggesting they reside in the cytosol in close proximity to the plant ribosomes. This paper aims to elucidate the physiological function of two nucleocytoplasmic RIPs from rice, in particular, the type 1 RIP referred to as OsRIP1 and a presumed type 3 RIP called nuRIP. Transgenic rice lines overexpressing these RIPs were constructed and studied for developmental effects resulting from this overexpression under greenhouse conditions. In addition, the performance of transgenic seedlings in response to drought, salt, abscisic acid and methyl jasmonate treatment was investigated. Results suggest that both RIPs can affect methyl jasmonate mediated stress responses.

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Ricin inhibition of in vitro protein synthesis by plant ribosomes

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.79.19.5935 ◽

1982 ◽

Vol 79 (19) ◽

pp. 5935-5938 ◽

Cited By ~ 44

Author(s):

S. M. Harley ◽

H. Beevers

Keyword(s):

Protein Synthesis ◽

In Vitro Protein Synthesis ◽

Plant Ribosomes ◽

Vitro Protein

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Functions of cytokinins

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1978.0081 ◽

1978 ◽

Vol 284 (1002) ◽

pp. 449-457 ◽

Cited By ~ 7

Keyword(s):

Cell Division ◽

Binding Protein ◽

Leaf Tissue ◽

Mechanisms Of Action ◽

Transfer Rna ◽

Biological Functions ◽

Higher Plant ◽

Rna Molecules ◽

Plant Ribosomes ◽

Stimulation Of

Mechanisms of action of cytokinins at the cellular and molecular levels are still unknown. Biological functions of cytokinins are presented through specific bioassay systems which are regarded as standard (delay of senescence of leaf tissue and stimulation of cell division) and which have been or may be biochemically investigated. These ‘biochemical functions’ of cytokinins are reviewed. The biochemical significance of the specific occurrence of cytokinins in transfer RNA molecules is discussed with respect to the question of the incorporation of labelled cytokinins into RNA molecules. Also, the significance of the cytokinin binding protein recently isolated from higher plant ribosomes is discussed.

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Über die Ribosomen aus Blättern von Allium porrum

Zeitschrift für Naturforschung B ◽

10.1515/znb-1962-1210 ◽

1962 ◽

Vol 17 (12) ◽

pp. 837-847 ◽

Cited By ~ 6

Author(s):

Ruth Ehring

Keyword(s):

Ribosomal Protein ◽

Ribonucleic Acid ◽

Dry Weight ◽

Allium Porrum ◽

Structural Protein ◽

Amino Terminal ◽

Plant Ribosomes ◽

Detergent Treatment ◽

Phenol Treatment ◽

Protein Moiety

Plant ribosomes prepared from growing leaves of Allium porrum were purified by differential centrifugation. Isolated ribosomes had a sedimentation constant of 79 —80 S and a ribonucleic acid content of at least 34% dry weight. The ribonucleic acid could be separated from the protein moiety by detergent treatment and was found to sediment as three fractions with sedimentation constants of 27 S, 9-10 S and 5 —6 S respectively. Similar ribonucleic acid components were obtained by phenol treatment of unfractionated leaf homogenates.A comparison of the nucleotide and amino acid composition of Allium porrum ribosomes with data reported for ribosomes from other plant and animal tissues revealed no significant differences. However, the lysine and arginine content of Allium porrum ribosomal protein was found to be significantly greater than that reported for the structural protein of the chloroplasts of the same species.Analysis of the amino terminal end groups of the Allium porrum ribosomal protein yielded predominantly serine.

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