Most cited article - PubMed ID 19390825
Chromatin structural rearrangement during dedifferentiation of protoplasts of Cucumis sativus L
Protoplast cultures are remarkable examples of plant cell dedifferentiation. The state of dedifferentiation is evidenced by changes in cell morphology, genome organization, as well as by the capability of protoplasts to differentiate into multiple types of cells (depending on the type of the stimulus applied). The first change in the genome structure is connected with large-scale chromatin decondensation, affecting chromocentres involving various types of these repetitive sequences. This paper describes not only the de- and recondensation of satellite DNA type I and 5S rDNA repetitive sequences, but it also compares the recondensation level of chromatin with the levels of oxidative stress which were decreased by using an antioxidant, as well as the capabilities of the antioxidative systems within protoplasts, during the first 72 h of their culture. It is demonstrated that the treatment of protoplasts with ascorbic acid not only decreased the level of oxidative stress but also positively stimulated the expression of the ascorbate peroxidase and catalase. It also led to a greater recondensation of the chromatin (when compared to the untreated protoplasts); in addition, it supported cell proliferation. It is concluded that large-scale genome relaxation is more directly connected with oxidative stress than with large changes in the expression of genes; and further, that its recondensation is related to the start of (as well as the level of) protection by the antioxidative systems.
- MeSH
- Ascorbate Peroxidases MeSH
- Cell Nucleus enzymology genetics metabolism MeSH
- Cucumis sativus enzymology genetics metabolism MeSH
- Catalase genetics metabolism MeSH
- Microsatellite Repeats * MeSH
- Oxidative Stress * MeSH
- Peroxidases genetics metabolism MeSH
- Protoplasts enzymology metabolism MeSH
- Plant Proteins genetics metabolism MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Ascorbate Peroxidases MeSH
- Catalase MeSH
- Peroxidases MeSH
- Plant Proteins MeSH
