Effect of tagetitoxin on the levels of ribulose 1,5-bisphosphate carboxylase, ribosomes, and RNA in plastids of wheat leaves

• Published in: Plant physiology (Bethesda) Vol. 84; no. 3; pp. 808 - 813
• Main Authors: Lukens, J.H, Mathews, D.E, Durbin, R.D
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01.07.1987
• Subjects: ARN; Bacterial plant pathogens; Biological and medical sciences; Chloroplasts; FEUILLE; Fundamental and applied biological sciences. Psychology; Gels; HOJAS; LEAVES; LIASAS; LYASE; LYASES; Messenger RNA; Microbe Plant Interactions; P. syringae; Pathology. Damages, economic importance; PEPTIDE; PEPTIDES; PEPTIDOS; Phytopathology. Animal pests. Plant and forest protection; PLASTE; PLASTIDIOS; PLASTIDS; PSEUDOMONAS; RIBOSOMAS; RIBOSOME; RIBOSOMES; RNA; Seedlings; TOXINAS; TOXINE; TOXINS; TRITICUM AESTIVUM; Wheat; Pseudomonadales; Monocotyledones; Ribosome; RNA; Enzyme; Phytopathogen; Biological activity; Cereal crop; Toxin; Phytotoxicity; Ribulosebisphosphate carboxylase; Enzymatic activity; Gramineae; Pseudomonas syringae; Protein synthesis; Angiospermae; Bacteria; Pseudomonadaceae; Spermatophyta; Photosynthesis; Triticum aestivum
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.84.3.808

Growth of wheat seedlings in the presence of the phytotoxin tagetitoxin produces pigment-deficient leaves of normal size and morphology whose cells contain only rudimentary plastids. We could not detect the accumulation of either the plastid-encoded large subunit or the nuclear-encoded small submit of the chloroplast stromal enzyme ribulose 1,5-bisphosphate carboxylase (RuBPCase) in western blots of protein extracted from leaves of such seedlings. Sucrose gradient centrifugation profiles showed that plastid ribosomes were essentially absent in toxin-treated leaf tissue while cytoplasmic ribosomes were relatively unaffected. Northern blot analysis of RNA in toxin-treated leaves showed a deficiency of plastid ribosomal RNA (16S and 23S) as well as reduced levels of plastid mRNAs for the large submit of RuBPCase and for the 32 kilodalton thylakoid QB polypeptide. Northern analysis also showed that the nuclear-encoded rbcS mRNA for the small subunit of RuBPCase is present in only trace amounts in toxin-treated leaves.