These authors contributed equally to the experimental work.
Reactive oxygen species produced by NADPH oxidase are involved in pollen tube growth
Article first published online: 21 MAR 2007
© The Authors (2007). Journal compilation © New Phytologist (2007)
Volume 174, Issue 4, pages 742–751, June 2007
How to Cite
Potocký, M., Jones, M. A., Bezvoda, R., Smirnoff, N. and Žárský, V. (2007), Reactive oxygen species produced by NADPH oxidase are involved in pollen tube growth. New Phytologist, 174: 742–751. doi: 10.1111/j.1469-8137.2007.02042.x
- Issue published online: 21 MAR 2007
- Article first published online: 21 MAR 2007
- Received: 23 October 2006 Accepted: 18 January 2007
- calcium signalling;
- cell expansion;
- hydrogen peroxide (H2O2);
- NADPH oxidase;
- Nicotiana tabacum (tobacco);
- polarised cell growth;
- • Tip-localized reactive oxygen species (ROS) were detected in growing pollen tubes by chloromethyl dichlorodihydrofluorescein diacetate oxidation, while tip-localized extracellular superoxide production was detected by nitroblue tetrazolium (NBT) reduction.
- • To investigate the origin of the ROS we cloned a fragment of pollen specific tobacco NADPH oxidase (NOX) closely related to a pollen specific NOX from Arabidopsis. Transfection of tobacco pollen tubes with NOX-specific antisense oligodeoxynucleotides (ODNs) resulted in decreased amount of NtNOX mRNA, lower NOX activity and pollen tube growth inhibition.
- • The ROS scavengers and the NOX inhibitor diphenylene iodonium chloride (DPI) inhibited growth and ROS formation in tobacco pollen tube cultures. Exogenous hydrogen peroxide (H2O2) rescued the growth inhibition caused by NOX antisense ODNs. Exogenous CaCl2 increased NBT reduction at the pollen tube tip, suggesting that Ca2+ increases the activity of pollen NOX in vivo.
- • The results show that tip-localized ROS produced by a NOX enzyme is needed to sustain the normal rate of pollen tube growth and that this is likely to be a general mechanism in the control of tip growth of polarized plant cells.