Characterization of protein synthesis by isolated rice mitochondria
Resource
Theoretical and Applied Genetics 86(1-2): 312-316
Journal
Theoretical and Applied Genetics
Journal Volume
86
Journal Issue
1-2
Pages
312-316
Date Issued
1993-04
Date
1993-04
Author(s)
Hwa Dai
Yih-Shan Lo
Chyr-Guan Charn
Manfred Ruddat
Kwen-Sheng Chiang
Abstract
Bacteria-free mitochondria were isolated from aseptically grown, etiolated and green seedlings of both cytoplasmic male-sterile (WA-type) and male-fertile rice (Oryza sativa L.). Protein synthesis in these isolated mitochondria was characterized by gel electrophoresis/fluorography and by the incorporation of [35S]-methionine into protein. In the presence of cycloheximide, a set of some 25 discrete polypeptides and an electrophoretically unresolved population were synthesized. This pattern of protein synthesis in organello was essentially the same in mitochondria isolated from both male-fertile and malesterile cytoplasms. Our data does not preclude the possibility, however, that the WA-type CMS possesses a tissue-specific and/or a low abundance mitochondrial protein(s), whose synthesis eluded detection under our experimental conditions. The synthesis of the mitochondria-encoded polypeptides by isolated rice mitochondria was inhibited by chloramphenicol and incompletely inhibited by erythromycin. A minor chloramphenicol-insensitive, cycloheximide-sensitive translation activity was found consistently to copurify with the mitochondria. This activity generated a reproducible electrophoretic profile of a poorly resolved, weakly labelled population of polypeptides and of a few conspicuous polypeptides, including a 42 kDa species.
Subjects
Mitochondrial protein synthesis
Cytoplasmic male sterility
Oryza sativa L
Chloramphenicol
Erythromycin
Cycloheximide
Translational activity
Publisher
Springer-Verlag
Type
journal article