Abstract
With the discovery of targeted gene replacement, moss biology has been rapidly advancing over the last 10 years. This study demonstrates the usefulness of moss as a model organism for plant photosynthesis research. The two mosses examined in this study, Physcomitrella patens and Ceratodon purpureus, are easily cultured through vegetative propagation. Growth tests were conducted to determine carbon sources suitable for maintaining heterotrophic growth while photosynthesis was blocked. Photosynthetic parameters examined in these plants indicated that the photosynthetic activity of Ceratodon and Physcomitrella is more similar to vascular plants than cyanobacteria or green algae. Ceratodon plants grown heterotrophically appeared etiolated in that the plants were taller and plastids did not differentiate thylakoid membranes. After returning to the light, the plants developed green, photosynthetically active chloroplasts. Furthermore, UV-induced mutagenesis was used to show that photosynthesis- deficient mutant Ceratodon plants could be obtained. After screening approximately 1000 plants, we obtained a number of mutants, which could be arranged into the following categories: high fluorescence, low fluorescence, fast and slow fluorescence quenching, and fast and slow greening. Our results indicate that in vivo biophysical analysis of photosynthetic activity in the mosses can be carried out which makes both mosses useful for photosynthesis studies, and Ceratodon best sustains perturbations in photosynthetic activity.
Original language | English |
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Pages (from-to) | 87-96 |
Number of pages | 10 |
Journal | Photosynthesis Research |
Volume | 83 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2005 |
Externally published | Yes |
Bibliographical note
Funding Information:We thank Prof. Ralph S. Quatrano, Washington University, Prof. David J. Cove, Leeds University, and Dr Maitrayee Bhattacharyya, Washington University, for collegial assistance. We thank Robert Thornton for bioinformatics assistance in developing oxygen evolution data analysis software. Grant supports awarded to H.B.P by the National Science Foundation and US Department of Energy, to L.E.T. by the National Science Foundation, to N.K. by the European Molecular Biology Organization and the International Human Frontier Science Program, and to I.O. by the Israel Science Foundation administered by the National Academy of Sciences are gratefully acknowledged.
Keywords
- Gene replacement
- Greening
- Moss
- PS II fluorescence
- Photosynthesis
- UV mutagenesis