Can a non-Mendelian Mutation Affect Both Chloroplast and Mitochondrial Ribosomes?
- 1 December 1973
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 70 (12), 3463-3467
- https://doi.org/10.1073/pnas.70.12.3463
Abstract
Chloroplast ribosomes isolated from a spectinomycin-resistant mutant (spr-1-27-3) of Chlamydomonas reinhardtii that displays non-Mendelian inheritance fail to bind labeled antibiotic, in contrast to ribosomes from wild-type cells. In vitro resistance of this mutant appears to result from the absence of a specific protein in the small subunit of the chloroplast ribosome. However, chloroplast protein synthesis in the mutant and wild type shows identical sensitivity to spectinomycin in short-term in vivo experiments where ribulosediphosphate carboxylase serves as the marker. Long-term experiments demonstrate that the mutant can grow in the presence of spectinomycin only when acetate is supplied as a carbon source. Mitochondrial structure and function of the mutant are not affected by the antibiotic, whereas chloroplast structure and function are. Apparently, the mitochondrion, rather than the chloroplast, of this mutant is resistant to spectinomycin in vivo. We hypothesize that the gene product of the spr locus is a protein common to both chloroplast and mitochondrial ribosomes. The mutant gene product, in vivo, confers resistance on mitochondrial, but not chloroplast, ribosomes. We suppose that the mutant spr protein loosely attaches to chloroplast ribosomes in vivo so that the antibiotic is bound and blocks protein synthesis, but it dissociates during isolation, resulting in loss of the binding site.Keywords
This publication has 32 references indexed in Scilit:
- Induction of Mendelian and non-Mendelian streptomycin resistant mutants during the synchronous cell cycle of Chlamydomonas reinhardtiiMolecular Genetics and Genomics, 1973
- Comparison of the Respiratory Chain of Neurospora crassa Wild Type and the mi‐Mutants mi‐1 and mi‐3European Journal of Biochemistry, 1973
- Cytochrome b in Neurospora crassa Mitochondria A Membrane Protein Containing Subunits of Cytoplasmic and Mitochondrial OriginEuropean Journal of Biochemistry, 1972
- A MAJOR POLYPEPTIDE OF CHLOROPLAST MEMBRANES OF CHLAMYDOMONAS REINHARDI The Journal of cell biology, 1972
- CHLOROPLAST STRUCTURE AND FUNCTION IN ac-20, A MUTANT STRAIN OF CHLAMYDOMONAS REINHARDI The Journal of cell biology, 1970
- Nuclear and chloroplast control of chloroplast structure and function in Chlamydomonas reinhardi.1970
- Formation of chloroplast membranes in Chlamydomonas reinhardi y-1. Effects of inhibitors of protein synthesis.1969
- Electrophoretic analysis of proteins from normal and cesium chloride-treated Escherichia coli ribosomesJournal of Molecular Biology, 1967
- Isolation and characterization of ribonuclease I mutants of Escherichia coliJournal of Molecular Biology, 1966
- MITOTIC REPLICATION OF DEOXYRIBONUCLEIC ACID IN CHLAMYDOMONAS REINHARDIProceedings of the National Academy of Sciences, 1960