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Light can rescue auxin-dependent synchrony of cell division in a tobacco cell line.

Qiao F, Petrásek J, Nick P - J. Exp. Bot. (2009)

Bottom Line: This synchrony can be inhibited by 1-N-naphthylphthalamic acid, an auxin transport inhibitor, and this process was accompanied by the disassembly of actin filaments.However, the synchrony could be rescued when the cells were cultured under white light or with exogenous indolyl-3-acetic acid.The rescue was most efficient for continuous far-red light followed by continuous blue light, whereas continuous red light was least effective.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany 1, University of Karlsruhe, Kaiserstrasse 2, Karlsruhe, Germany.

ABSTRACT
Pattern formation in plants has to cope with ambient variability and therefore must integrate environmental cues such as light. Synchrony of cell divisions was previously observed in cell files of tobacco suspension cultures, which represents a simple case of pattern formation. To develop cellular approaches for light-dependent patterning, light-responsive tobacco cell lines were screened from the cell line Nicotiana tabacum L. cv. Virginia Bright Italia 0 (VBI-0). The light responsive and auxin-autonomous cell line VBI-3 was isolated. As in the progenitor line VBI-0, cell divisions are synchronized in VBI-3 during exponential growth phase. This synchrony can be inhibited by 1-N-naphthylphthalamic acid, an auxin transport inhibitor, and this process was accompanied by the disassembly of actin filaments. However, the synchrony could be rescued when the cells were cultured under white light or with exogenous indolyl-3-acetic acid. The rescue was most efficient for continuous far-red light followed by continuous blue light, whereas continuous red light was least effective. These findings are discussed in the context of phytochrome-induced auxin biosynthesis and auxin-dependent synchrony of cell division.

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The light-dependent rescue of the division pattern in the presence of NPA depends on light quality. Frequency distributions of cell number per file were constructed for incubation with 5 μM NPA under equal fluence rates (26.0 μmol m−2 s−1) of continuous red (A), blue (B), or far-red light (C). Each distribution is based on ≥2000 cell files from two independent experimental series. Error bars indicate the SE.
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fig3: The light-dependent rescue of the division pattern in the presence of NPA depends on light quality. Frequency distributions of cell number per file were constructed for incubation with 5 μM NPA under equal fluence rates (26.0 μmol m−2 s−1) of continuous red (A), blue (B), or far-red light (C). Each distribution is based on ≥2000 cell files from two independent experimental series. Error bars indicate the SE.

Mentions: Since irradiation with white light reversed the effect of NPA on the division synchrony, an experiment was performed to determine whether this reversal was dependent on light quality (Fig. 3). When the cells were cultured under continuous red light, only a very weak recovery of the pattern was observed (Fig. 3A). This recovery was more significant for continuous blue light, especially for files with <5 cells, but it was incomplete for longer files (Fig. 3B). However, for irradiation with continuous far-red light, the frequency of cells with four and six cells was clearly elevated (Fig. 3C) and the resulting frequency distribution became congruent with that observed in the absence of NPA (compare Figs 3C and 2B). Thus, continuous far-red light can overcome the effect of NPA on synchrony.


Light can rescue auxin-dependent synchrony of cell division in a tobacco cell line.

Qiao F, Petrásek J, Nick P - J. Exp. Bot. (2009)

The light-dependent rescue of the division pattern in the presence of NPA depends on light quality. Frequency distributions of cell number per file were constructed for incubation with 5 μM NPA under equal fluence rates (26.0 μmol m−2 s−1) of continuous red (A), blue (B), or far-red light (C). Each distribution is based on ≥2000 cell files from two independent experimental series. Error bars indicate the SE.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2803214&req=5

fig3: The light-dependent rescue of the division pattern in the presence of NPA depends on light quality. Frequency distributions of cell number per file were constructed for incubation with 5 μM NPA under equal fluence rates (26.0 μmol m−2 s−1) of continuous red (A), blue (B), or far-red light (C). Each distribution is based on ≥2000 cell files from two independent experimental series. Error bars indicate the SE.
Mentions: Since irradiation with white light reversed the effect of NPA on the division synchrony, an experiment was performed to determine whether this reversal was dependent on light quality (Fig. 3). When the cells were cultured under continuous red light, only a very weak recovery of the pattern was observed (Fig. 3A). This recovery was more significant for continuous blue light, especially for files with <5 cells, but it was incomplete for longer files (Fig. 3B). However, for irradiation with continuous far-red light, the frequency of cells with four and six cells was clearly elevated (Fig. 3C) and the resulting frequency distribution became congruent with that observed in the absence of NPA (compare Figs 3C and 2B). Thus, continuous far-red light can overcome the effect of NPA on synchrony.

Bottom Line: This synchrony can be inhibited by 1-N-naphthylphthalamic acid, an auxin transport inhibitor, and this process was accompanied by the disassembly of actin filaments.However, the synchrony could be rescued when the cells were cultured under white light or with exogenous indolyl-3-acetic acid.The rescue was most efficient for continuous far-red light followed by continuous blue light, whereas continuous red light was least effective.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany 1, University of Karlsruhe, Kaiserstrasse 2, Karlsruhe, Germany.

ABSTRACT
Pattern formation in plants has to cope with ambient variability and therefore must integrate environmental cues such as light. Synchrony of cell divisions was previously observed in cell files of tobacco suspension cultures, which represents a simple case of pattern formation. To develop cellular approaches for light-dependent patterning, light-responsive tobacco cell lines were screened from the cell line Nicotiana tabacum L. cv. Virginia Bright Italia 0 (VBI-0). The light responsive and auxin-autonomous cell line VBI-3 was isolated. As in the progenitor line VBI-0, cell divisions are synchronized in VBI-3 during exponential growth phase. This synchrony can be inhibited by 1-N-naphthylphthalamic acid, an auxin transport inhibitor, and this process was accompanied by the disassembly of actin filaments. However, the synchrony could be rescued when the cells were cultured under white light or with exogenous indolyl-3-acetic acid. The rescue was most efficient for continuous far-red light followed by continuous blue light, whereas continuous red light was least effective. These findings are discussed in the context of phytochrome-induced auxin biosynthesis and auxin-dependent synchrony of cell division.

Show MeSH